Cebek FE-138 module is a single rail 24VDC stabilized power supply. It can deliver a maximum of 4A, the output is fully regulated and short circuit protected. A PCB mounted pre-set potentiometer is supplied to adjust the output voltage (22.5 – 26.5VDC), to allow for long cable runs and supply voltage variations. The FE-138 module has a small toroidal transformer mounted on the circuit board. and LED to indicate its operating.