If the coin devices for the showers are installed directly in the wet cells, safety extra-low voltage is often required. This means that the coin devices do not work with the normal mains voltage of 230 volts, but with 12 volts or 24 volts of low voltage. Then the solenoid valves must be designed for the same voltage. A transformer that provides you with the extra-low voltage is then required for operation. We would be happy to make you a complete offer.