A customers CNC router with 2 MA860H drivers(Leadshine Technology Co., Ltd.). At First,All axis drive/move correctly, however when the Z and A (rotational) axis are connected (even when not in use) there is a large amount of "noise" generated that affects the NPN type homing switches. When these 2 units are switched off/disconnected from the supply the homing switches work correctly. How is that happened?
Can you show me wiring diagram of the whole CNC router?
NPN homeing switch should have an independent power supply. If it share a same power supply with the Leadshine MA860H or other drives. It wll be interfered.
Further more, if this problem still can not be handled. You can try to use a shield motor cable. And make sure the motor house grounding. NPN homing switch also need adopt shield signal cable.