The explanation of terms related to or describing our products can be found in the glossary

How do I find the user manual, the data sheet or the description for a given product? (0.1.1)

Enter the complete article number or type into the search field (the autocomplete offers known terms). The data sheet and the description (where applicable) are listed on the page of the product and together make the user manual. In the product tables click in the details column of the unit in question.


An article number or type name is not found. (0.1.2)

Wrong input? Kniel article numbers consist of 8 digits and follow the pattern 123-456-78. The dashes are significant.
Or perhaps you entered the article number of a customer specific unit. Although the number might be correct we are not allowed to make these information freely available. If your Kniel power supply is part of a machinery, contact the vendor or maker of that machine.
Or maybe you entered the article number of an outdated unit whose availability guarantee (10 years after announcement) ran out.


Does Kniel make customer specific power supplies? (0.2.1)

We develop, built and deliver customer specific power supplies. This starts with a special front panel  to match the rest of the control cabinet and goes up to complete power supply solutions fitted to your requirements.


Does Kniel build complete sub racks? (0.2.2)

We build sub racks, wired to customer specifications and equipped with our power supplies and peripherals.


Customer information (0.2.3)

We publish customer information on a as needed basis. These are not necessarily information about our products but certificates and declarations. The documents are listed in the glossary below the appropriate keyword.


Where do I find firmware, drivers and other software like DemoApp or LabVIEW VIs for download? (0.3.1)

The complete software you need is delivered on a data carrier with our power supply. The latest version of the software is listed on the product page of the power supply and can be downloaded from there.


Where do I find information concerning REACH? (0.3.2)

Registration, Evaluation, Authorisation and Restriction of CHemicals
You find our current declaration (in german and english) as PDF here:


Where do I find 3D data, eg IGES files? (0.3.3)

We offer IGES files for many of our products. Where available you find them on the respective product page. If you could not find the 3D data you need, please ask us.


Where do I find declarations concerning RoHS? (0.3.4)

You find our current declaration (in german and english) as PDF here:


Where do I find information concerning the Dodd-Frank Act? (0.3.5)

You find our current declaration as PDF here  in german and english.


Where do I find Lantronix Device Installer and COM Port Redirector Installer setup files? (0.3.6)

You can download the files from the Lantronix  website.


How do I know which type is the successor of an outdated unit? (0.4)

In the product tables you find the article number of the successor type next to the old type. On dedicated pages the article number of the successor type is listed in the table.


Who can help me if a Kniel product needs repair or calibration? (0.5.1)

We offer to repair and calibrate our products. You find information about the handling on our page Services


Who can help me when I need technical support? (0.5.2)

Contact our sales department in our main branch in Karlsruhe. Use the contact form or send us an email to


Is Kniel certified according to DIN EN ISO 9001? Where do I find the DIN EN ISO 9001 certificate for download? (0.5.3)

Kniel is certified according to DIN EN ISO 9001. Download the current version (in german and english) of the certificate here:


Is it mandatory to connect the „Extern ON/OFF“-input? (1.1.1)

No, it isn't. The „Extern ON/OFF“-input need not be connected if the functionality is not needed.


How does the „Extern ON/OFF“-input work? (1.1.2)

For units equipped with an „Extern ON/OFF“-input you find the necessary information in the description of the unit in question.


Is it mandatory to connect the „Enable“-input? (1.1.3)

The „Enable“-input works more or less like a negatived „Extern ON/OFF“-input. For safety reasons we use the technique in power supplies with output voltages above 100V, this is why the „Enable“-input can only be found on these units. An external auxilliary voltage has to stress the „Enable“-input constantly to keep the power supply in normal operation.


What are sense leads for? (1.2.1)

Sense leads measure the actual value of the voltage directly at the input of the consumer load and enable the power supply - to compensate for any voltage losses on the load leads. Please refer to the data sheet and descriptions of the units in question for the maximum amount of compensation.


Is it mandatory to connect the sense leads? (1.2.2)

No, all our power supplies are operational without connected sense leads. Sense leads should only be used if the power supply has to provide a constant feeding voltage over long load lines and the load might vary.


What are virtual sense leads? (1.2.3)

A function called "virtual sense leads" is implemented in our DSP-controlled power supplies (series energy, energy installation) (firmware version 05.00.06 and later). The function can be used to compensate a known voltage drop over the wiring between Power supply and load without using physical sense leads. The voltage drop to compensate is programmed in the power supply by setting the internal resistance which is equal to the external resistance causing the voltage drop. The function "virtual sense leads" is independent from using physical sense leads (that is connecting separate wires between the appropriate connector pins on the power supply with the input of the load). While the power supply using the physical sense leads can adjust for changing situations, the function "virtual sense leads" can only compensate for a static voltage drop.
See also: What is the internal resistance of a power supply? (1.2.4)


What is the internal resistance of a power supply? (1.2.4)

Due to physical preconditions every practical current source has an internal resitance. The internal software of our DSP-controlled power supplies (series energy, energy installation) allows the manipulation of this value (firmware version 05.00.06 and later). This allows to emulate a battery (setting the internal resistance to a positive value) or to compensate voltage drops that occur in the wiring between power supply and load (setting the internal resistance to a negative value).
See also: What are virtual sense leads? (1.2.3)


Can power supplies from Kniel be connected in parallel? (1.3.1)

Power supplies of the same type equipped with a PA-pin on the connector can be used in parallel to increase the over all output power. The PA-pins of all units used in parallel must be connected with each other. If you need to operate power supplies in parallel that do not have a PA-pin, please get in touch with us. In most cases, we can offer you a not very complicated solution. If the power supplies in question can operate in „Load Sharing“ mode, this mode should be used. Not every power supply has this feature, please refer to the data sheet and description of the unit in question.


What does the contact named PA in the pin assignment for? (1.3.2)

To connect the PA-pin is only necessary when operating power supplies in parallel. To avoid damaging the units, the PA-pins of all units operated in parallel must be connected with each other. In case of one power supply triggering it's overvoltage protection, all other power supplies connected to it will get switched off. When a power supply is not operated in parallel, the PA-pin may not be connected with each other.


Are power supplies from Kniel prepared for redundancy operation? (1.3.3)

Yes, all power supplies from Kniel be used for redundancy operation. Shows the connector pin assignment one or more pins named +R, the necessary decoupling diode is already interegrated in the unit. If not, an external decoupling diode (available as additional accessory) must be used. Potentially existing PA-pins may not be connected. If the power supplies in question can operate in „Load Sharing“, this mode should be used. Not every power supply has this feature, please refer to the data sheet and description of the unit in question.


What does the LS-input for? (1.3.4)

Power supplies with a LS-input (LS = load share) have an integrated load share bus. During parallel or redundant operation the load share bus will take care to balance the output currents of the individual power supplies within the range of +/- 10% (with active voltage regulation). During current regulation mode the load share bus is inoperable. For more information refer to the unit's data sheet and description.


What is PFS? (1.4.1)

The power fail signal (PFS) should always be activated if the power supply at the input of the load is at risk. As a result emergency routines can be started in good time if a controlling device or computer unit fails and thus errors can be avoided. The monitoring relates to the input and output voltage.


What is VME? (1.4.2)

The VME-signals in principle offer the same functionality like the power fail signal. But according to the VME standards not only one, but an additional second signal with a timed delay is generated.


What does .../OP1 in the article short text stand for? (1.4.3)

OP1 is the abbreviation for option 1. Units equipped with OP1 are equipped with additional (compared with units without any option) signals, e.g. PFS, Load-Share, Enable. For more information refer to the unit's description.


What does .../OP2 in the article short text stand for? (1.4.4)

OP2 is the abbreviation for option 2. Units equipped with OP2 are equipped with all additional signals (e.g. PFS, Load-Share, Enable) that OP1 includes plus a secondary decoupling diode for redundant mode. For more information refer to the unit's description.


What is VF? (1.4.5)

VF stands for voltage fail signal. VF gets triggered if the actual output voltage drops more then 5% below the target value. Depending on type VF is available either at the male connector or via the digital interface, some units may offer both features. If VF is available at the male connector, the signal is potential free (decoupled from the rest of the power supplies circuitry by means of optocoupler). Example of use: by monitoring VF during the power-up of the power supply the user gets a confirmation when the output voltage has reached the target value and thus is available for the consumer load.


What is FS? (1.4.6)

FS stands for failure signal. The signal becomes active if either an overvoltage at the output of the power supply or over temperature inside the unit is detected. The signal will also be triggered if both conditions are met. The signal is available at the male connector of the power supply and is potential free (decoupled from the rest of the power supplies circuitry by means of optocoupler).


How to program Kniel power supplies? (1.5.1)

Accordingly equipped Kniel power supplies can be programmed in different ways. Depending on series different output values (voltage, current, power) can be programmed and read out. The way, how the programming is done - how the values are preset - depends on series. Some units expect the preset done by external resistors, others need an external voltage or have a digital interface. Some units offer the possibility, to preset working modes by jumpers. For more information refer to the unit's description.


What does “V set R” mean? (1.5.2)

This notation shows, which output value (in this case V, the output voltage) can be coerced by which means (in this case set R, resistance). The example shows a unit, whose output voltage can be influenced by using an external resistor (fixed or potentiometer). A fixed resistor will limit the output voltage to a given value, a potentiometer allows the variation of the output voltage. The value of the output voltage changes linear analog the value of the resistor: divide the value of the resistor by two and the value of the output voltage will be half what it was before. Exact values and instructions depend on series and unit type and can be found in the unit's description.


What is the difference between CAN-Bus and CANopen? (1.5.3)

CAN-Bus is a broadcast, differential serial bus standard. Kniel utilizes the high-speed model according to ISO 11898-2. For data transmission on layer 1 and 2 of the CAN-Bus the protocol CANopen according to CiA Draft Standard 301 (EN 50325-4) is used.


Does the digital interface allow to control Kniel power supplies remotely? (1.5.4)

Yes, all control and monitoring functions realised in the power supply like limits, protections, status requests and so forth are accessible via the digital interface off-the-shelf.


What is OVP (over voltage protection) german: ÜSS (Überspannungsschutz)? (1.5.5)

A protection circuit integrated in the power supply switches the unit off if the voltage at the output exceeds a given value.


How should a pre-fuse be dimensioned? (1.6.1)

The data sheets of our power supplies contain information about the integrated fuse and the inrush current. Following the principle of “selective coordination” (see this PDF) a pre-fuse must be dimensioned higher than the built-in fuse of any of the following power supplies. Additionally the pre-fuse needs to cover higher inrush currents than any of the following fuses (for the relevant data refer to the data sheet of each power supply). The worst-case values for the inrush current are valid for repowering the unit after a short interruption (≤ 1 minute). Due to the fact that in most applications repeated powering up can not be avoided, always the values for worst-case should be the base of dimensioning. Should you want to let multiple power supplies share the same pre-fuse, only an estimate can be made. After dimensioning the pre-fuse the calculation should be evaluated by tests. The maximum inrush current of the pre-fuse equals the sum of the combined inrush currents of all power supplies when cold (“unit cold”). For an assumed worst-case the pre-fuse must resist at least half of the combined inrush currents under worst-case conditions. Usually the integral value for suitable fuses is sufficient if fuses with the proper tripping characteristic (characteristic K or slow-blow) are used.


What does ppm/K (as found in data sheets or catalogues) mean? (1.6.2)

With this indication it is possible to calculate the the maximum drift of the output voltage (deviation of the output voltage) against the temperature of the surrounding air (ΔU = 0.0002 x ΔT x Uout).


What does Nemko stand for? (1.6.3)

Nemko is a certified institute in Norway, comparable with the german VDE. Units that are proven to meet certain regulations by Nemko are classified as certified and may carry the Nemko logo (The N-mark).


What does the integrated electronic load do? (1.6.4)

The integrated electronic load in our digitally programmable power supplies is one of the circuits that protect the power supply. It serves as the load for the energy buffers at the output of the power supply if the voltage setting changes from a high to a low value. On the other hand the electronic load prevents overloading of the output circuit in case of feedback energy, e.g. emitted from an electric motor running in generator mode. For more information refer to the unit's description.


What do the special charaters in the input voltage on the identification label / and * mean? (1.6.5)

We use the special characters / and * on the identification label to indicate the input voltage of a power supply. If a power supply supports more then one input voltage or input voltage range, we separate them with a /. The default value set ex works is prefixed with a *. Eg 115/*230 Vac marks a power supply with two nominal input voltages (115 Vac and 230 Vac) and was delivered set for 230 Vac.


What is Bureau Veritas? (1.6.6)

Bureau Veritas  is an international operating company in testing, inspection and certification.


Over voltage protection (1.7)


Do you offer matching connectors for your power supplies? (2.1)

Yes, we do. To all our power supplies we offer the matching female connectors, plugs etc. Pease note that like all other accessories connectors are not included and must be ordered separately. You find information about appropriate plugs, connectors and other accessories on the respective product page or in the product tables when you click on Details.


What does U and HP stand for? (3.1.1)

U is one of the main dimension units of the 19”-system and is used to indicate the width of the unit. One U equals to one fifth of an inch or 5.08mm. HP is the second main dimension unit of the 19”-system and is used to indicate the height of a unit. One HP - front panel related - equals to 1.75” or 44.45mm. We offer powers supplies for 3U or 6U installation hight and with different installation widths within a wide range of output power.


Why is the front panel wider than the housing of the power supply? (3.1.2)

This is to make sure that an airflow between the neighbouring units in a 19”-rack is possible. This airflow is a crucial part of the cooling system. With this wider front panel the user does not have to think about putting dummy plates between the units to produce the necassary distance.


Is it normal, that the power supply needs quite some force to be pushed into the 19”-system? (3.1.3)

No. In most cases it has been missed to rotate the right guiding rails by 180° before mounting them into the rack.


How to mount rail guides properly? (3.1.4)

Rail guides are directional. Rail guides for the right side of the power supply must be mounted inverted.


Can power supplies be mounted on a wall in any position? (3.2.1)

Power supplies with integrated cooling fans can be mounted in any position. But care must be taken to make sure the air intakes and outlets are free and not covered. Power supplies without integrated cooling fan must be mounted in a position to allow the surrounding air to develop a convection stream through the power supply in order to cool it. If this is not possible, measures must be taken to secure a consistent flow of air through the power supply (e.g. by external cooling fan).


How does one find out, which wall bracket goes with which 19”-unit? (3.2.2)

We offer matching wall brackets for most of our 19”-primary switchers and DC/DC-converters. Basically the wall bracket has to be mounted on the side of the unit that's next to the connector. An exception are our units either 8U or 12U wide, here the wall bracket has to be mounted on the side of the unit that is further from the connector. Wall brackets series WF (for wall mounting with screw fastening) or WFS (for DIN-rail mounting) are mounted on a flat side wall, wall brackets series WG (for wall mounting with screw fastening) or WGS (for DIN-rail mounting) are mounted upon a potentially existing side wall cooler. Please consider that power supplies can be ordered completely equipped with mounted wall brackets and mounting devices for DIN-rails. No wall brackets are available for our power supplies 4U wide. If you need power supplies in this power range, please consider our Modules. For some housings we offer special forms of wall brackets. Please contact us if you need information.


Can I order power supplies ready for mounting on walls or DINrails ex works or do I have to retrofit the wall bracket and/or rail mounts? How can I order this? (3.2.3)

On the product page of the power supply in question you find all wall brackets suitable for the unit.


What is the difference between the housing variants for the 19-inch System (Block, Cassette, Modul, Steckkarte, Steckcompact, Volleinschub)? (3.3.1)

See the glossary where we show the different housing variants.


What is PQube? (4.0)

PQube is a modular system for monitoring the quality and power of a power source. Starting with different basic modules (PQ1, PQube Classic, PQube 3) and adding peripherals (current transformers, Ethernet module, etc) and accessories (currency sensors, attenuators, environmental sensors, etc) it is possible to implement a made-to-measure system for monitoring an a.c. network.
you can find a demo installation of a PQube Classic (PQube 2) here: PQube Demo .


Wohin kann ich die Unterlagen für eine Bewerbung schicken? (5.0)

Falls Sie sich auf eines unserer Stellenangebote oder initiativ bewerben wollen, senden Sie Ihre vollständigen Bewerbungsunterlagen an Bitte senden Sie keine Duplikate an eine andere Adresse bei Kniel.
Verwenden Sie bei Anhängen nach Möglichkeit das Format PDF.
Vermeiden Sie proprietäre Formate wie z.B. DOC oder DOCX und senden Sie uns keine Archive wie ZIP oder RAR.


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Fixed voltages
for 19” systems

Ajustable power supplies
for 19” systems

Programmable power supplies
for 19” systems

energy for 19” systems

Fixed voltages
for wall mounting and DIN-rail mounting

Adjustable power supplies
for wall mounting and DIN-rail mounting

Programmable power supplies
for wall mounting and DIN-rail mounting

energy installation for wall mounting

Firmware, Flash-Tool, Drivers

General information


Kniel System-Electronic GmbH · Kurzheckweg 8 · 76187 Karlsruhe · Germany ·