Small current generator circuit

Electrical personnel sometimes need to perform periodic overcurrent or calibration on overcurrent relays, thermal relays, etc. , and must use a current generator . A small current generator can be made by using a safety lamp transformer
, voltage regulator and ammeter .     The picture shows the self-made marine current generator circuit . It consists of a switch, fuse , voltage regulator, safety lamp transformer, ammeter, etc. Connect it according to the line in the picture. After passing the zov power supply voltage into the voltage regulator , it is adjusted. voltage, the secondary current of the portable lamp transformer can be adjusted from 0 to about 40MA, and is continuously adjustable. It can be used to meet general overcurrent verification.