Product Categories

Battery Chargers

Our battery chargers are a solid basis for stabilizing railway vehicles’ on-board supplies. The devices are suitable for all common one- or three-phase VAC input voltages. They guarantee separated supply for battery and on-board consumers and come up with numerous safety features that you can customize according to your wishes – for example with a CAN bus interface.

High Voltage a. Emergency Start Converters

At Grau Elektronik’s, this product category covers the high voltage range from 750 VDC up to 3000 VDC: On the one hand, well-established converters for contact wires, that are made for providing 24 or 110 V at railway crossings, using the 750 VDC contact wire’s voltage. What is special and very practical about it: The devices are meant to be inserted and kept running directly at the contact wire, without any additional transient filters or external fuses. On the other hand, our reliable emergency starting equipment, for 1500 VDC and 3000 VDC applications: They are able to provide downstream devices and their control electronics in a safe way in the case of a deep discharged battery, as well as to initiate a system start at any time, using contact wire voltage.

Capacitor Chargers

Our capacitor charging devices are the product of choice when it comes to stabilize DC link voltage systems. The voltage/current control at the converter’s output is the basis for DC link capacitors’ safe charging, as it is used for example in locomotives and tramways for emergency compressor supplies or for providing energy reserves for system-critical shutdown processes.

Voltage Converters

Our wide range of voltage converter products offers you numerous solutions for both DC and AC input voltages when it comes to provide downstream electronics in a safe way. Designed for a long lifetime up to 20 years (according to EN50155), they prevent reliably sudden voltage drops or dynamic fluctuations of on-board voltages, using their internal energy storage circuits. Thus, control units, sensor circuits, actuators or drive units in vehicles are solidly provided by the converters’ controlled output voltage – even under very harsh conditions as they are prevailing in railroad operations.

Power Sources

You can also rely completely on us for choosing your right power supply: Countless applications, just as softstarting electric motors or providing solenoid valves, require a highly available current source. For realizing that, Grau Elektronik offers you current- or voltage-controlled converters that can be used with different VDC or VAC input voltages. The output powers range from 50 W up to 55 kW (for controlled rectifiers).


They come into use where primarily only VDC voltages are available on board railway vehicles. However, for running common electric devices, VAC voltage is needed: Hence, plugs in the vehicle can be used based on battery voltage, even building up an own 230 VAC onboard network would be an option. In practice, the inverters will provide for example laptops, cleaning equipment or VAC fans, one- or three phase with very high crest factor. The products from this category even allow for the setup of an interruptible power supply – in connection with our battery chargers for example.

Custom Request

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