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About Schleifenbauer

Who is Schleifenbauer?

Schleifenbauer is a European manufacturer of rack PDUs and intelligent energy meters for data centres, located in 's-Hertogenbosch (The Netherlands).

What is the company's core-business?

Schleifenbauer specializes in rack and distribution panel power management solutions for datacenter and infrastructure applications. We live to assist facilities and IT managers to build their premium, high availability, sustainable and easy to use power distribution system, by delivering no-compromise custom configured products and services.

How are Schleifenbauer products produced?

Schleifenbauer PDUs and energy meters are adjusted to the infrastructure of your data centre, not the other way around. You can compare our configuration and production process to that of Lego™: Using only a limited number of building blocks, an endless number of final products can be created.

Our vision regarding our products

The Schleifenbauer Intelligent Power Distribution Unit (PDU) is designed to distribute power for many years and without  problems.

The PDU is equipped with a specially developed Schleifenbauer databus which makes it possible to read and  manage many PDUs with a single IP address. An ethernet port is added to each PDU so that next to the advantages of a  databus, a whole range of new options has become available. Schleifenbauer PDUs merges the interests between IT and  infrastructures, making it a real bridge builder.

Where is Schleifenbauer located?

Schleifenbauers headquarters and production site is located in 's-Hertogenbosch, in The Netherlands. From here we are centrally located in the FLAP-region (Frankfurt, London, Amsterdam, Paris).

Why choosing 'Made in Holland'

Our products are 'Made in Holland'. To ensure our quality, we manage the production process in-house and in collaboration with our distinguished and reliable local partners.

What are the main industries where Schleifenbauer is active?

Schleifenbauer is mainly active in the data centre industry (commercial and private), and in several other industries like industrial production and yacht building. We are mainly working for European customers, but we also deliver to companies abroad.

How quality management is ensured?

Schleifenbauer is ISO 9001:2015 certified in accordance with the international standard for quality management.

Products and features

Introduction of the Schleifenbauer PDU

The Schleifenbauer Intelligent Power Distribution Unit (PDU) is designed to distribute power for many years and without problems.

The PDU is equipped with a specially developed Schleifenbauer databus which makes it possible to read and manage many PDUs with a single IP address. An ethernet port is added to each PDU so that next to the advantages of a databus, a whole range of new options has become available. Schleifenbauer PDUs merges the interests between IT and infrastructures, making it a real bridge builder. Monitoring capabilities will be described in detail within this manual in upcoming sections.

The PDU may contain:

  • metered outlets
  • switched outlets
  • metered and switched outlets
  • passive outlets

Customers can configure the number and types of outlets of their PDU to their requirements by using Schleifenbauers customization tool (product selector) when ordering.

What are the different types of PDUs?

We provide 5 types of PDUs, with different functionalities:

  1. Basic PDU
    This PDU offers 'standard' power distribution without metering and management-options.
  2. Metered PDU
    This PDU provides 'cumulative' (input) metering.
  3. Monitored PDU
    This PDU has metering options per outlet.
  4. Switched PDU
    This PDU has switching options per outlet.
  5. Managed PDU
    This PDU had both metered and switched outlets.

What are the product specifications?



0° to 60° Celsius


-30 to +2000 m

Relative humidity

10 to 90% non-condensing

Level of pollution



Indoors IP20

Class of equipment

Class I

Protective rating


Conditions of use


Voltage: single-phase 100-230 VAC; three-phase 230/400 VAC  

Frequency: 50/60 Hz

Permitted load: see product information on your PDU

Accuracy: EN 50470-1/3 class B, EN 62053-21: class 1, ± 1%

Wire colour code: 

  • L1 = BROWN
  • L2 = BLACK
  • L3 = GREY
  • N (neutral) = BLUE

Which interfaces are integrated in the PDU?

There are several interfaces integrated in the PDU:

  • (embedded) web interface
  • Modbus/TCP
  • SNMP (Simple Network Management Protocol)
  • (SP)API (Schleifenbauer Products Application Programming Interface)

In our manual (admin section) you will find information about the “Interfaces” that describe the technology to communicate via your LAN (Local Area Network) with the Schleifenbauer databus.

Which quantities our PDU can measure?

The PDU is capable of measuring a number of quantities, either at the input, output or an optional sensor.

Measurements quantities are shown below:

Which connectors are available for my PDU?

We deliver different types of connectors, suitable for your situation:

  1. CEE 7/7 (Schuko/UTE)
  2. IEC320 C14
  3. IEC320 C20
  4. IEC60309 1 phase
  5. IEC60309 3 phase
  6. BS 1363
  7. GST 3/18
  8. T13
  9. T23
  10. Cable connection
  11. Terminal connection

More information: https://www.schleifenbauer.eu/en/pdu/discover-yourpdu/

Can I choose the cable entry of my PDU?

Sure you can! You can choose the location of the cable entry:

  • Top
  • Base
  • Frontside
  • Rear-side

More info: https://www.schleifenbauer.eu/en/pdu/discover-yourpdu/

Can I choose the length of the input cable?

Sure! We can make your PDU with an adjustable cable length according to your wishes.

Cable specifications:

  • Cable length is adjustable
  • Low Smoke Zero Halogen (LSZH)
  • Oversized diameter

More info: https://www.schleifenbauer.eu/en/pdu/discover-yourpdu/ 

Can I choose the color of my PDU?

Sure! We provide the housing of our PDU's in different Colors.

Possible options:

  • Black
  • Green
  • Orange
  • Blue
  • Red
  • Yellow

More info and color scheme: https://www.schleifenbauer.eu/en/pdu/discover-yourpdu/#housing

Can I add fuses and surge protection on my PDU?

In combination with a Schleifenbauer PDU, there is an unrestricted choice of fuse type, including:

  • Miniature Circuit Breaker (MCB)
  • Thermal fuse
  • Glass cardridge fuse holder
  • PASCO cartridge holder

Also surge protection is possible, with the following characteristics:

  • Protects PDU against surges
  • Hot swap
  • Can be replaced by a data centre engineer

Which output types are possible in a PDU?

Your PDU can be fitted with various (types of) outputs. You can configure both the number and type of outputs yourself.

Different types of outputs:

  • IEC320 C13 (also version with IEC-lock)
  • IEC320 C19 (also version with IEC-lock)
  • CEE 7/3 (Schuko)
  • CEE 7/5 (UTE)
  • IEC60309 1 phase (IP44/IP67)
  • IEC60309 3 phase (IP44/IP67)
  • BS 1363
  • GST 18/3
  • T13
  • T23

More info about PDU-outputs:

Which type attachment of brackets are available?

We deliver different types of attachment brackets:

  • 19” rack mounting brackets
  • Tabletop mounting brackets
  • Mounting plates for sunken installation
  • Profile clamps
  • Toolless Mounts

Can I get my own logo on the PDU housing?

Yes, this is possible. We often make rack-PDU's with the logo of the customer lasered in the aluminium housing.

Selection and quotation

How to configure a Schleifenbauer product?

With our Schleifenbauer Product Selector, you easily can select and configure (if needed) you PDU or Energy Meter.

Click here for our Product Selector:

How fast will I receive a quote?

You can request us for a quote via our Schleifenbauer Product Selector, which we will send to you within 1 business day.

Can I request for support by selecting or configuring my product?

If you have any questions or issues by selecting or configuring your Schleifenbauer product, you can give us a call. Our Inside Sales team will provide you with your request.

You can call us on: +31 (0)73 523 02 56 or send us an e-mail: info@schleifenbauer.eu

Do I have to configure a product by myself?

This is not necessary. If one of the suggested products in our Schleifenbauer Product Selector suits you, you can directly send your request for a quote.

Only if you want to change one ore more elements on the suggested product (PDU), you can choose for configuration and configure it according to your wishes.

Can I make an appointment with an Account Manager?

Sure you can! If you have a project to discuss about, you can make an appointment.

You can send your appointment request to info@schleifenbauer.eu, your account manager will contact you to plan a date and time.

For more contact details, please check: https://www.schleifenbauer.eu/en/contact

Is Schleifenbauer working with resellers?

Yes, we have different resellers in different European countries. For more information and details about this topic, please contact us!

Installation & connection


I received my order, what are the contents of the package?

The Schleifenbauer Intelligent PDUs are shipped in a cardboard box. Where applicable, dispose the packaging material in a responsible manner, in accordance with local regulations. All of the materials used for packaging can be recycled. Immediately after receipt, check whether you have received your order in a complete and undamaged state.

The following items are delivered for each PDU:

  • Fixing materials: These can be attached to the PDU (19’’ or table-mounting brackets), or are delivered separately if they have been ordered separately;
  • The installation manual (one per shipment);

Please note that the PDU User Manual can also be found online at https://www.schleifenbauer.eu

Are there some visual elements to inspect before installation?

After opening the cardboard box and removing the packaging material, the PDU should be checked visually.

The PDU should not be put into operation if damage is detected in a way that safe and proper operation cannot be guaranteed. In such cases, please contact Schleifenbauer Products BV.

Note that, in the case of PDUs that are equipped with an overvoltage protection, the overvoltage protection and the respective overcurrent protection (if applicable) must be inspected on a regular basis.

What are the main requirements for installation?

  • The PDU must be installed in a restricted access location
  • Socket-outlet must be installed near the equipment
  • Socket-outlet must be easily accessible
  • Installation by expert personnel only (adequately trained persons according to NEN EN 50110-1, with full observance of the specifications of NEN EN 50110-1 and NEN 3140)
  • After installation: default passwords / RC4 keys ​MUST​ be changed (see manual, part III (administrator manual)

What are the technical installation requirements?

Before installing and putting the system into operation, check whether the characteristics of the electrical system to which connection is to be made correspond to the product specifications.

  • The Schleifenbauer Intelligent PDU has been designed for connection to electrical systems that comply with IEC 60364 or in the Netherlands, NEN 1010
  • The voltage, maximum permitted current and the number of phases must be correct. This information is displayed on the front side of the PDU.
  • The maximum permitted power must be taken into account with regard to the maximum length and the diameter of the connecting lead.
  • The values and characteristics of the in-series protective devices must match the PDU and the protective elements included in it.
  • The environmental factors must correspond to the product specifications.

What kind of tools do I need for installation?

The following tools are needed to install the PDUs:

  • cage-nuts with bolts and washers
  • suitable screwdriver

How to mount a PDU horizontally?

Each 19’’ rack bracket of a PDU has 4 holes for horizontal mounting in 19” racks. The holes are positioned so that an appropriate fixing hole is always available for a PDU with a profile height of 1.5 U. Using one or two of the 4 holes allows mounting without wasting space.

How to mount a PDU vertically?

In case of a PDU for vertical mounting, the connection lead is fed through a hole in the upper, bottom or front face.

How to mount a PDU without tools?

Toolless mounting is created by making attachment points on the rear of the PDU housing. There is a wide range of cabinet brackets available, all in which you can hang the PDU without using tools.
Toolless Mounting can be done as single PDU or double PDUs (see image).

Mounting brackets can be custom made by Schleifenbauer.


How to mount a PDU on a flat surface?

A table -top-mounting gives the profile possibility to be mounted to a flat surface (tabletop). This arrangement is used for:

  • vertical mounting to the bracing beams in the 19” cabinet
  • fixing to a mounting plate
  • mounting between the 19” uprights: the profile attaches to the front of the uprights

The holes on the brackets are located as far as possible to the outside so that it can also fit and tighten the bolts if a swivel gland has been placed on the short side.


How to mount a PDU with sunken installation? (to prevent hot spots in a cabinet)

When power leads might block the flow of hot exhaust air, especially in case of a 600mm wide cabinet, it is necessary to create additional space for airflow. This can be done by using the “sunken installation brackets”. Because of the shape of the bracket, it is possible to ‘partially sink’ the profile into the cabinet and save space.

These mounting plates can be used for many different cabinets.

How to achieve maximum mounting flexibility by using profile clamps?

The clamps, made of spring steel, can be installed in the position of your  choice. The clamp fits around the PDU profile and is secured with a  fastening screw. Our advice is to use one clamp for every 50 cm of profile  length.

Connection (ethernet, databus and sensors)

How to connect the PDU to LAN?

10/100 Mbps LAN Ethernet port

Connecting the PDU to a Local Area Network (LAN) provides  communication through an Ethernet network. Multiple PDUs can share  the same ethernet connection by using the databus (Bridge or Hybrid  mode). The RJ45 connector for the network  cable must be plugged into the silver Ethernet port: 

Connect the RJ45 Ethernet cable to the Ethernet port on the PDU and to  the Ethernet connector on the LAN device; when connected, the orange  LED – marked “lnk” – will blink.

What is a Schleifenbauer data bus?

The intelligence of Schleifenbauer PDUs makes it possible to read and manage devices remotely over IP. It's possible for example to access the databus via the web interface, MODBUS and SNMP.

The databus provides a wide range of options: it has adequate support for custom configurations that are desired by the user.

Databus and power distribution are separated in the Schleifenbauer PDU. All operations on the databus do NOT interfere with the distribution of power to the connected equipment in the racks.

Advantages of the databus:

  • Easy to build: Pick a PDU and connect it to a local area network, daisy chain the rest of the PDUs and a databus is created.
  • Remote updating of the firmware.

Explanation of the image:

  • The PDU that is connected to the LAN must be in “BRIDGE” mode (red); this is the MASTER device.
  • all “daisy chained” devices must be in “HYBRID” mode (blue); these are the BRIDGED devices.

How to connect a data bus?

There are three black communication ports. One is marked as sensorport,  the other two as databus ports (in and out). The left databus port is the  “incoming” databus port. The right databus port is “outgoing”. This is a  MUST HAVE for devices in bridge mode. For devices in hybrid mode it is a  NICE TO HAVE. The serial databus in the Schleifenbauer PDU uses CAT5  patch cables. 

  • Data  will  be  send  and  received  by  both  ports  but  to  close  the  databus ring, it is recommended to follow the connection diagram to ensure maximum performance.

How to create a databus using Schleifenbauer Gateway?

In the image above a small databus-ring with four PDUs connected to the Schleifenbauer Gateway can be seen.

The Classic PDU has NO ethernet port, so a (Schleifenbauer) Gateway is needed in order to get PDUs connected to your LAN. The sequence of devices does not affect the performance of the Gateway or the databus. More devices in the databus equals more communication. This does result in a slightly slower data transmission.

Our advise is to always close the databus-ring. To do so, connect the last device in the databus to the Gateway (blue lines in the image). In a closed databus ring the Gateway is able to reach all connected devices through IN and OUT databus-ports (clockwise and counter-clockwise).

Advantage: One IP-address makes it possible to collect data from a number of connected Schleifenbauer-devices (not only PDUs but also the Schleifenbauer DPM-range (=energy meters).

Disadvantage: Gateway uses 1U in terms of rack-space.

Problem solving: If the Gateway fails, it's possible to change to the next configuration: using the “bridge” mode.

Note: Databus communication takes 0,2 seconds per query (e.g. input measures block). Therefore we advise to create rings with a maximum of 50 devices which means that querying each device once will take approximately ten seconds.

How to create a databus to LAN without a Getaway?

The image above shows a small databus-ring with only four devices connected to a LAN: a Classic PDU and PDU with ethernet port. The device connected to the LAN must have an ethernet port and be in “BRIDGE" mode. All other devices should be in “Hybrid" mode. The BRIDGED device takes over the function of the Schleifenbauer Gateway.

It's possible to connect numerous Schleifenbauer devices to the device which is in BRIDGE mode: PDUs and DPM3's (= three channel energy meter) as well as Classic PDUs and DPM27 (= 27 channel energy meter).

The sequence of devices does not affect the performance of the databus-ring. But, the more devices you place in the databus-ring, the slower data transmission will be. The image shows that different

Schleifenbauer devices can be connected in a ring which makes the system easily scalable to customer needs. It is advised to close the databus ring. Connect the last device in the databus to the device in BRIDGE-mode.

In a closed databus ring all connected devices are reachable through IN and OUT databus ports (clockwise and counter-clockwise).


  1. When only using devices with ethernet port: only the device in BRIDGE mode uses one IP-address.
  2. It's possible to select any device connected to the local area network as long as it is in BRIDGE mode.
  3. Investment in a Schleifenbauer Gateway is not necessary.
  4. The system is easily scalable.

Disadvantage: MySQL and SMTP can not be used.

Note: Databus communication takes 0,2 seconds per query (e.g. input measures block). Therefore we advise to create rings with a maximum of 50 devices which means that querying each device once will take approximately ten seconds.

How to connect sensors to a PDU?

The PDU has a RJ12 connector sensor port which can connect one of the  following:

  • a digital temperature sensor
  • a combined sensor for temperature/humidity
  • one or multiple dry switch contacts

Plug and play 
Sensors are automatically recognized by the PDU and will update the  display and menu accordingly.

Warning: Use Schleifenbauer sensors only

How to connect a NO/NC contact on a Classic PDU & Ethernet PDU

The sensor port makes use of the RJ12 6P6C standard (= 6 position, 6 conductor). To connect a NO/NC contact on the PDU sensor port, you have to make use of pin 1 and pin 6 ; as shown in the figure below.

How to connect a NO/NC contact on a G3 PDU?

3rd generation PDUs and DPMs are equipped with a USB-port and are able to operate two NO/NC dry switch contacts.



The current php API uses a single class for interfacing with SPBUS devices. It implements only the IPAPI protocol. For more information on the used protocol refer to the ’SPBUS protocol v2’ document, for more information on the php API download the API from the Schleifenbauer website and investigate functionality using the examples and source code.

Perl API

The perl API uses a single package for interfacing with SPBUS devices. It implements both the SPBUS protocol and the IPAPI protocol. For more information on the used protocols refer to the ’SPBUS protocol v2’ document, for more information on the perl API download the API from the Schleifenbauer website and investigate functionality using the examples and source code.


SNMP can be used to communicate with a SPBUS device's registers. At the time of writing this document, SNMP v1, v2, and v2c are supported. Also supported are SNMP traps, for which a trap destination server can be configured on a device.

The current SPBUS device traps are:

  • Network connectivity
  • SNMP authentication failure
  • Device status code
  • Temperature alert
  • Input current alert
  • Output current alert
  • Input voltage alert
  • Output current drop alert
  • Input current drop alert
  • Sensor change alert
  • Ring state changed

All of these SNMP traps can each be enabled or disabled.

For SNMP OID (object identifier) information, the MIB (management information base) files can be found on the Schleifenbauer website. Please refer to the SNMP RFCs for more information on SNMP.


The webapi behaves similarly to a RESTful API. It is possible to retrieve a register's information from a SPBUS device using resource requests. The webapi does not depend upon a specific implementation and is therefore explained using the messages send over to the SPBUS device over the TCP/IP connection. Note that details (namely ones related to the Authentication token) are omitted from this document. For more information on the webapi refer to the webapi documentation: https://docs.schleifenbauer.eu/Documentation/WEBAPI_documentation.pdf


Modbus is a communication protocol which allows different commands (functions) including reads/writes to and from device registers (memory locations on a device in the modbus network). Modbus is therefore useful for SPBUS device communications considering SPBUS devices use registers to interface with its hardware. For more information on SPBUS device data over modbus, refer to the ‘Schleifenbauer hPDU Modbus Specification’ document.


A user might want to implement their own API or directly integrate SPBUS protocol communications in their custom software. For these people there exists the SPBUS protocol description. This document describes the SPBUS protocol in detail. Note that the SPBUS protocol can be used either over RS485, or IPAPI although IPAPI uses additional packet construction steps.

SPBUS protocol: https://docs.schleifenbauer.eu/Documentation/SPBUS_protocol.pdf

Monitoring via device display

What are the elements of a (intelligent) PDU display?

The intelligent PDU features a display with scroll buttons, LEDs and some ports for connecting accessories. Please keep in  mind that PDUs may differ in configuration and may or may not not have a display.  

  1. PDUs ​without​ an Ethernet port are called Classic PDUs. Firmware for Classic PDUs are in the FW1xxx – range
  2. This option is called “Local alert reset” and must be activated through the interfaces
  3. USB-port on g3 (generation 3) only ; to be used for firmware up- and downgrade (from FW2.52 and newer)

How to change settings locally via PDU display?

Changing settings locally via the PDU itself is ​not​ possible! You have to use one of the interfaces.

Note: See the ​'administrator part​' in our manual how to changes the settings

How to stop a blinking display via a local alert reset?

Since Firmware 2.50 alerts are represented on both display and web interface. For example:

The displayed text shows directly which alert has occurred.  

Why do alerts occur? 

Alerts are signal flags after an event occurred. For example, if the measured temperature and the environmental  conditions exceed a configured level or threshold, the PDU will generate an alert. This resolves in: 

●  SNMP trap (optional).
●  The screen of the PDU will start blinking.
●  The screen of the PDU will jump to the Alert page which provides information on what happened.

After the temperature has dropped again, the event is cleared but the alert still exists. The display will blink until you  “reset” (=clear) the alert. 

The LCD display only flashes when an alert is active.  


● Press any button to stop blinking for a short period: blinking will stop so you can read the display
● Resetting  the  alert  can  be  done  by  pressing both scroll buttons simultaneously; when cleared the display will stop blinking (Note: this possibility must be activated on your device; see Admin part of this manual)

Note: You can reset the alert but by doing so, you do not resolve the cause of the alert! If the alert condition is still present the alert will reappear. 

How to check load balance, temperature/humidity or status of the NO/NC contact?

The image shows three phases (L1, 2 and 3). The actual information is presented in amperes but is also graphically displayed. The higher the load, the more the bar is filled. The graphical bar is related to the maximum PDU rating (in the image it is 32A). In this image, there is almost zero load, only on L3 there is a small 0.1A.

DS = status of NO/NC contact (O = open; C = closed)

Te = temperature (degrees C) *

RH = relative humidity (%)*

*only visible when the corresponding sensor has been connected.

How to get back to the first page on the display?

If there are alerts, first clear these by pressing both scroll buttons (see: “How to stop blinking display via a local alert reset")

If the alerts are resolved or there are no alerts (no blinking display), press both scroll buttons (see arrows in image) to quickly jump to the first page.

How to check an outlet status locally?

In the “outlets” display you can see how many outlets the PDU has and what their individual state is. 

An overview of the possible states:

  • 0= off
  • 1= on
  • s= scheduled to go off
  • S= scheduled to go on
  • p= power cycling

Note: every row on the display shows the state of 9 outlets. So the first ends with outlet 9, the second row starts with outlet 10.

How to check input and/or outlet measurements?

The scroll buttons allow the user to scroll through the pages.

The total amount of pages varies and depends on the PDU configuration. For example: The more outlets the higher the total amount of pages. In the “input page” example page 4 of 29 is displayed.

In the lower left corner of the “input page” example, the subject of the shown information on this page is visible as “INPUT L2", which is short for input measurements of L2. So, when you search for outlets, scroll through the pages until the “outlet” sections are reached. An example is shown in the “outlet page" image.

Displayed information can be:

  • I= current [A]
  • P= power [W]
  • U= voltage [V]
  • Pf= power factor [%]*
  • Et= energy total [kW]
  • Es= subtotal energy [kW]

(*Pf = real power ÷ apparent power)

Example: input page

Note: “Input x” shows the name of the Input. This information can be configured from the Web Interface, Inputs tab or from the other interfaces.

Example: outlet page

How to read measurements of optional sensors?

Option 1: load page

Sensors are displayed on the “Load" screen whenever there are less than three sensors in use. When adding more sensors, one or more pages are added to the display to show the sensor readouts (see image):

DS = status of NO/NC contact (O=open; C=closed)

Te = temperature (degrees C)

RH = relative humidity (%)

Option 2: sensor pages

The sensor measurements are displayed in the following format:

< channel number > < sensor type > = < value >

The sensor type is indicated by a letter. The letters are abbreviations for the sensor type as follows:


  • T = temperature [°C]
  • H= humidity [%]
  • R= residual current [mA]
  • A= AC residual current [mA]
  • D= DC residual current [mA]
  • B= Branch residual current [mA]


  • I = dry switch contact
  • S = error status
  • Y = activity
Example: sensor page 1 of 2
Example: sensor page 1 of 2

How to read Branch Residual Current measurements?


When the PDU is equipped with a Residual Current Sensor (RCS), measurements of the residual current are shown in the sensor pages.

In parts of Europe, electrical installations must incorporate devices designed to protect people and prevent fires: the residual current device, or RCD. A RCD disconnects the circuit if the total for the incoming and outgoing currents in the monitored phases and their neutral conductor exceed a threshold, for example : L1 + L2 + L3 + N > 30 mA.

Data center practice: Residual Current Monitoring in relation to Residual Current Devices

Many devices inside a datacenter operate a switching power supply. These power supplies usually leak a bit of energy to the protective earth, so even without failing hardware some residual current will occur. In order to rule out a single dangerous fault from a sum of harmless smaller faults, one needs to set up a network of RC-sensors and monitor them permanently. RC-monitoring can take place in many forms. The Schleifenbauer RC-sensor offers Class B metering, thus enabling our customers to set-up an RC-monitoring system that prevents dangerous situations inside the datacenter.

Where to measure residual current?

When monitoring residual current at a single location it is not possible to determine whether the measured value is a sum of many small currents or a single larger (dangerous) one. For that reason it contributes to the safety of the personnel inside a data center when residual currents are metered at several points.

How to find the PDUs unit address, tag, name or location?

You will find all customer specific information about the PDU in the “Custom” display.

  • Adr = address of this unit on the data bus
  • Tag = vanity tag
  • Nme = device name
  • Loc = location of the device

Note: The device name and tag can be changed using the WEBAPI

How to view PDU connection information?

You will find all information related to the PDUs network connection in the IPv4 Link and IPv6 Link pages.


Lnk = current Ethernet link status of the device

St = IP status:

  • DHCP: Acquiring/Bound, Static, Static fallback
  • ‘-‘ when there is no link

IP = IP address of the device

NM = subnet mask of the device

GW = IP address of the Gateway or Router

MAC = MAC address of the device

IPv6 Link:

The IPv6 link will show up to 3 IPv6 addresses. The first one will be your link-local address which will always start with FE80: The second and third will be your LAN and WAN address respectively.

How to check in which mode & protocol the PDU is running?

In the “IP Interfaces” display you can find information about the device mode in which the PDU is working:

  • Mode = hybrid, data bus, bridge, colocation, …

The display shows the status, and which protocol & port number is used for:

  • HTTP
  • API
  • Modbus
  • SNMP
  • IPMode (IPv4, IPv6 or both)

Note: When there is active communication with the PDU, the interface colors will be inverted. Text is white and the background is blue. When the interface is used, the text becomes blue and the background white. 

How to check the installed firmware version?

In the “About” page you can find the firmware version that is currently installed on the device. In this example the firmware version is FW02.50.

Note: It is important that the most recent firmware version is installed on all devices. This ensures correct operation of the device and databus. Firmware and service tools can be found at “downloads” on the Schleifenbauer website.

How to check for traceability information?

In the “About” page you can also find information regarding serial number, product information and Schleifenbauer order number.

  • ID = unique hardware address of this device’s controller
  • SN = serial number (also found on the PDU housing)
  • Prt = product identification (also found on the PDU housing) 
  • Ord = order number for internal Schleifenbauer uses
  • Ph = number of phases of this device
  • O = total number of outlets on this device
  • S = number of switchable outlets on this device
  • M = number of metered outlets on this device

Remote monitoring and operating (via Webinterface)

How remote operating and monitoring works?

Schleifenbauer PDUs allow remote administration which enables users to switch on or off selected outlets, monitor usage data and set/receive alerts on configured thresholds. In addition various connection parameters can also be configured through various protocols.

The Schleifenbauer web interface is an easy to use tool to configure the PDU. 

How to login?

By default the web interface is enabled. To navigate to the web interface the IP address and port number can be found on the display of the PDU.

How to select your language?

The login screen makes it also possible to select English or German as language.

How the user interface works?

Connected devices (only in bridge mode)

The left pane of the image below shows a list of connected devices on the databus. Also the databus management functions can be found in this section such as:

  • Scan databus
  • Initialise zero addresses to sequence
  • Reset all alerts

Device information

After selecting a connected device, you see measurements/information and get access to the remote operating functions, in the right pane.

How to change and save settings?

The web interface is protected against accidentally changing settings. Related to your user profile, you might have permission to change information: see the “Permission model”. To open protected cells, you first have to click the “Locked” sign and the status will change to “Editable”.

When ready, click “Editable” or click the “Save changes” icon if shown, and the sign will turn into “Locked”.

How to change SNMPv3 settings?

SNMPv3 user settings can be configured in the web interface: tab “Interfaces”, block “User management”.

To change the settings of a specific user click the ‘edit’ button. Then check the ‘change snmpv3 settings’ checkbox to edit the snmpv3 settings. When finished, click the ‘save user’ button.

Note: A classic PDU without an ethernet connector that is running on firmware 1.xx doesn’t have a device type register. As a result some features do not work using SNMP.

Not working using SNMP on a Classic PDU:

  • Input subtotal reset per phase
  • Outlet reboot
  • Power (W) and Power (VA), invalid value (0.0)

How to use the ‘device list’ section?

The web interface will show a list of all devices connected to the bridge-PDU on the left pane (or below the blue header when using narrower displays) only when the PDU is configured in Bridge mode.

Initially this list is empty but will be filled while the web interface is loading data from the bridge-PDU. A user must click the configuration icon on the right side of the device list and choose “scan data bus”. A selected device is marked – yellow line – in the device list (left pane). Users can switch between devices just by clicking the row in the device list.

Information and settings about the currently selected device can be seen on the right pane of the web interface. Next to the configuration icon is the ring icon. This icon shows if your ring is properly closed, or if it’s open.

The example below shows an open ring. The example on the bottom of this page shows a properly closed ring. It’s closed by connecting the “out” of the last device in the ring to the “in” of the first device. A closed ring guarantees redundancy of all data between the master “bridge” device and the addressed “hybrid” device.

Note: Device list only appears when the connected device is in “bridge” mode.

Note: When using multiple devices in a ring, make sure the one connected to the local network is in bridge mode and all others are in hybrid mode.

How to add new devices on an existing ring?

When new devices are added to a ring, the firmware might find several devices with unit address 0.

All connected devices require a unique unit address to function properly. Having duplicate unit addresses will result in warnings (see image).

It is not possible to set all addresses all at once!

In this example (see image), four devices are found. Device [1] is the bridged device so it is best to set this unit address last. So start with [4] which is the device on top in the list that was found first.

  • Click < set address >
  • A new screen will appear; check if the correct device is selected.
  • Fill in the new < unit address >
  • Click < ok >

A “ write error” will occur which is correct: you just changed the unit address so it can not be reached anymore at its old unit address. Please click

When you perform a < rescan > you see that all devices are correctly addressed.

How to manage login, usernames & passwords?

The PDU user authentication model provides five different accounts which can be used to access the web interface and SNMPv3.

In the web interface the user accounts are in decreasing order of access rights: super, admin, power, user and viewer.

It should be noted that super is only intended for use by Schleifenbauer personnel. The access rights of the different user accounts, together with databus and unauthenticated ethernet, are shown in the table below:

The default password for each profile initially equals the username of the profile. For example the default password for the ‘admin’ user profile is “admin”.

Each user can change all more restricted user passwords, in addition to their own password. Please fill the ‘Username’ and ‘Password’ fields accordingly and then click login or press enter.

How to change factory passwords?

We advise our customers to change all standard passwords during setup of the system to prevent unauthorized access.

In tab “Interfaces”, block “User management” passwords can be changed.

There are five login profiles:

  1. Viewer = viewing only
  2. User = Viewer + resetting alerts and switching outlets
  3. Power = User + resetting subtotals
  4. Admin = all administrator rights
  5. Super = Factory profile

How to change the Ethernet link settings?

The “ethernet link speed and duplex mode”-setting is set to auto negotiate by default. The link speed and duplex mode are automatically configured with the link partner (e.g. Network Switch).

You can also configure the link speed and duplex mode to a fixed setting. You can choose from the following options:

  • Autonegotiation
  • 10 Mbps Full Duplex
  • 10 Mbps Half Duplex
  • 100 Mbps Full Duplex
  • 100 Mbps Half Duplex

Note: When this setting is changed, make sure the configuration of the link partner is changed accordingly! Deviations in speed/duplex modes prevent users from connecting to the PDU remotely. If this setting is changed to an invalid value by accident and users are unable to connect, change the setting of the link partner to the same setting in the PDU to be able to access the PDU again. If this doesn’t solve the problem: Try a factory reset.

How to change the hostname?

It’s possible for users to change the hostname of their devices. A hostname consists of a Schleifenbauer prefix and the serial number by default.

There are three options:

  1. Custom hostname
  2. Schleifenbauer prefix combined with a sysname
  3. Back to default value

These options are available in the “Interfaces” section of the web interface.

Custom hostname: Change the hostname value, save and restart PDU.

Schleifenbauer prefix and sysname: Add custom name to sysname value, save and restart.

Back to default value (Schleifenbauer prefix and serial number): Empty sysname value, save and restart. Or empty hostname first and then empty the sysname.

How to configure the IP settings manually?

The IP settings can be manually configured by using the web interface:


  • Go to the , tab < Interface >, block < Network Configuration >
  • Disable DHCP
  • Fill in the “Static IP Settings”
  • Restart the CPU: go to tab < System >, block “Reset”

When using ‘DHCP fallback to static IP’, it is recommended to enter a unique IP address for each PDU. This approach prevents all of the PDUs from being assigned the same IP address in the event of a faulty DHCP server. This prevents PDUs from being assigned to the same IP address.

How to setup IPv6?

Since firmware version FW2.44, IPv6 support has been introduced in the Schleifenbauer PDU. This feature is disabled by default.

An IPv6 address consists of 8 blocks of 4 hexadecimal digits separated by columns ( : ). Consecutive blocks 1 2 of zeroes can be substituted with a double column ( :: ) and leading zeroes can be omitted. The default static IP is “::" which translates to 0000:0000:0000:0000:0000:0000:0000:0000.

IPv6 Autoconfigure (SLAAC)

By default the PDU will try to obtain its IPv6 address through a process called “stateless local address auto configuration" (SLAAC). This setting can be turned off in the web interface by setting “IPv6 Autoconfigure" to “disabled". The PDU will try to find a router by sending router solicitation packets via ICMP6 using its link-local address. This means that a IPv6-enabled router must be available on the network and it must send ICMP6 router advertisement packets in order for the PDU to obtain a valid IP6 address. When “IPv6 fallback to static IP" is set to enabled in the web interface, the PDU will use it's configured static addresses as fallback when a router cannot be found.

Static IP

To use static IPv6 addresses the PDU must either have it's “IPV6 Autoconfigure" setting disabled or “IPv6 fallback to static IP" enabled in the web interface. To change the static IPv6 addresses, fill in a valid IPv6 into fields “IP6 address 1" and/or “IP6 address 2"; see next chapter. These settings can be found under “interfaces → network configuration".

How to configure IPv6?

The IPv6 settings can be found in the PDUs web interface at the tab < Interfaces> block < Network Configuration >.

The PDU will always generate a Link-local address which starts with “FE80::".

This address is auto-generated and loses its scope at the first encountered network node.

The IPv6 addresses can be found on the web interface or on the “IPv6 Link" page on the PDU display as shown in the image below.

To enable IPv6 support, the user must login to the PDU using the IPv4 address presented on the display. After login, select the tab “interfaces". In section network configuration is a drop-down box called “IP Protocol select". The default value of this drop-down box is “IPv4 only".

To enable IPv6 set this to either “IPv6 only" or “IPv4/IPv6 dual-stack", which means the PDU can communicate through both protocols.

Note that selecting “IPv4 only" or “IPv6 only" requires one of the filtering ranges to be all zero (allow all addresses). This is to prevent users from locking themselves out. Filtering ranges can be configured afterwards when the user has connected to the bridged and/or hybrid PDU using the protocol previously specified.

Enabling IPv6 adds an additional page to the PDU display named “IPv6 LINK" (see image). The current IP Mode is also visible if the user navigates to the “IP INTERFACES" display.

How to set up IPv6 address filtering?

IPv6 address filtering settings can be found at tab < Interfaces > block < Access control > from within the web interface.

The web interface shown in the image below allows users to specify three IP ranges which grant access, anything outside of these IP ranges will be blocked. If the user wishes to configure only a single range, all three boxes should be filled with that range.

Setting any address with prefix “0" will allow any address to access the PDU web interface, SNMP, modbus etc.

Setting the address to “::" (all zero's) and the prefix to a number between 0 and 128, will limit the allowed IP scope to the network the PDU is connected to. Filtering will then be disabled.

Note: All “allowed IPv6 range" fields must be filled in order for the filter(s) to have effect!

IPv6 example

Setting a filter of A76F::D222:12FF:FEB0:F48/64 will allow any address starting with A76F:0000:0000:0000: (A76F::) but other addresses such as A76A::32D4:731B:F17B:6 will be blocked. For a more detailed explanation see the Wikipedia page on IPv6 subnetting. Please note that filtering requires a complete and valid IP address to 4 function properly.

IPv6 filtering ranges

PDUs current IPv6 addresses.

How to configure SSL certificates?

For increased security the communication can be encrypted using SSL certificates.

Key Generation

Certificates with a public and private key can be uploaded with the web interface. The certificates are used for the authentication phase of the handshake. These certificates can be generated in 3 steps:

  1. Generate a private key
  2. Generate a CSR (Certificate Signing Request) with the private key.
  3. Create a self-signed certificate with the CSR.

The following private keys will be supported:

  1. RSA (1024 bit)
  2. Elliptic Curve (secp256r1/ prime256v1 and secp384r1)

TLS Cipher Suites Supported:

The TLS cipher suites are listed in the following format (example):


  1. TLS prefix
  2. Key Exchange algorithm (DHE) (Excluded for static keys)
  3. Authentication algorithm (RSA)
  4. Encryption algorithm (AES)
  5. Encryption strength (256)
  6. Encryption mode (GCM)
  7. MAC (SHA284)

The certificate uploaded is used for the “Authentication algorithm" (RSA or Elliptic Curve). Other options (Key Exchange, Encryption etc) are selected from what the client lists as supported in the “Client Hello". The following cipher suites are supported:

Static Key with RSA:


Ephemeral Elliptic-curve Diffie–Hellman with elliptic curve:


Elliptic-curve Diffie–Hellman with elliptic curve:


Note on self-signed certificates

At the moment only self-signed certificates are supported.

Certificate Generation

OpenSSL can be used to generate the private keys and certificates. We can provide scripts for this purpose if requested.

How to add SSL certificates?

  1. Unlock “Webserver” block
  2. Select or add HTTPS to the webserver section “HTTP/HTTPS”
  3. Select the port (default: 443) you want to use for communication with HTTPS
  4. Click “Save Changes"
  5. Unlock “Certificates” block

  6. Set “Use custom certificates” to enabled

  7. Load your certificate into an editor, select the text and paste it in the appropriate box

  8. Load your private key into an editor, select the text and paste it in the appropriate box

  9. Click “Save Changes”

  10. Go to the system tab and reboot the PDU to actualize your new configuration.

How to upgrade the firmware?

In the Firmware Updater Tool-manual you will find all necessary actions to up- or downgrade
For updating the firmware you need a tool which can be found on our website on the download page. On this page a manual is available.


In the updater manual is exactly described what to do when upgrading the firmware. In summary:

  • first download and upgrade this Gateway firmware (when used in the data bus); in this firmware an updater tool is integrated
  • download the zip file of the Firmware Updater tool
  • download the required firmware
    • Classic PDU: SPFW-​01​..- serie
    • PDU: SPFW-​02​.. -series
  • unzip the updater tool
  • run the updater tool; via this updater tool the firmware will be downloaded to all devices in the ring.

The PDU firmware updater tool is available for Windows, Mac OS and Linux. The Gateway firmware is available for Windows en Mac OS

How to stop the alert signaling?

From firmware 2.40 and newer it's possible to select a duration time after which the alert will be cleared after the cause of the alert is resolved. It's no longer necessary to clear the alert on the PDU or via an interface after the event which led to an alert is resolved.

Important: Alerts are always caused by issues that need to be resolved as soon as possible. So it is important that the alerts are recorded/logged in a management system.

Maintenance & Troubleshooting

What about firmware upgrade and downgrade?

The development of the PDU firmware is an ongoing process. With every new release not only issues are fixed, but new features are also added. There will be miscellaneous minor improvements and fixes, but also general performance and stability improvements. Always make sure the firmware is up to date to ensure the PDUs are equipped with the latest technology and newest features.

If devices are connected in a databus ring, upgrading of all attached devices can be done remotely! During the upgrade process the power distribution won’t be interrupted. Our firmware, firmware tools and manual can be downloaded from our website and can be used for free.

When a Schleifenbauer Gateway is present in the databus make sure the Gateway firmware is upgraded first. This firmware is listed on the documentation page of the Schleifenbauer website. The latest firmware, manual and updater tool is listed on the support page of our website.

How to upgrade the firmware using SPST?

SPST is short for “Schleifenbauer Products Service Tool”.

This program aims to aid customers in analyzing and maintaining their network of Schleifenbauer PDUs and DPM-energy meters. SPST provides the following features:

  • Users can “quick scan” the status of the databus.
  • Users can up-/downgrade firmware easy and simple.
  • Users can remotely mass configure databus devices.
  • SPST will decrease problem solving lead time.

SPST and it’s manual can be downloaded at our website. We advise our customers to read the manual before using SPST. One of the purposes of the SPST tool is to make firmware updating and mass configuration easier.

How to upgrade the firmware using a USB?

All G3 products are equipped with a USB port near the PDU display. USB support is enabled by default if it hasn't been explicitly disabled by the user. To start the update process make sure that USB support is enabled in the web interface.

This can be done in the -> settings section at the web interface. Alternatively, it is possible to enable or disable the USB interface with the Modbus or SNMP interface.

Download the latest firmware from https://docs.schleifenbauer.eu/?dir=Firmware .

The firmware is provided as a single ZIP-archive. Please extract the entire contents of this archive onto a blank FAT32-Formatted USB stick . Safely remove this USB stick from the PC and insert it into a PDU. The upgrade starts automatically.

How to perform a “Software reset”?


When Interface-settings are changed the CPU has to be restarted in order to adapt to the new settings. In the web interface a pop up will appear when a restart is required:


A software reset can be performed in the web interface. It is important to understand that a software reset has no impact on power distribution of the PDU. So a reset can be performed at any time without having to interrupt the power supply and without losing the settings in the PDU.


The PDU can be restarted using a paperclip or a similar sized object to press the reset button. This button is mounted behind the hole labelled as ‘rst’ on the PDU next to the Ethernet connection port.

How to perform a “Factory reset”?

If the PDU can no longer be accessed through the local area network, for example, because settings have been changed, restoring IP access may be required.

The following procedure causes the PDU to adopt various default values, which allows it to be redetected on the network without losing any of the other settings in the PDU. However, the power supply must be interrupted in order to perform this restore procedure! The procedure is described in five steps:

  1. Interrupt the power supply to the PDU.
  2. Restore the power supply.
  3. Wait for one second and afterwards press the reset button using a paper clip.
  4. Wait for another second and press the reset button again.
  5. Wait for another second and press the reset button again.

The PDU has now adopted the default values for the IP settings. The access control fields and the web server settings have also been returned to the standard values.

Please note that because the power is removed, outlets will also be out of power. Hence, during this process there won’t be any measuring.

Please keep in mind that kWh totals will NOT be reset during this process.

How to reset peak current? And other dips or peaks?

Example: The “overcurrent alert at” is set on 5.00A in the < input > tab. At a certain moment in time an alert in the web interface dashboard appears.

Check the Inputs-tab and notice the peak current of 8.30A in this example image:

Clear the alert locally or by the reset button in the section in the System-tab, the peak current will not be cleared.

This is done manually by clicking the button in the section of the System-tab:

How to contact Schleifenbauer for service and support?

Please contact us in case there are questions regarding our products.

Fill in a customer support request via: https://www.schleifenbauer.eu/en/support/