I started to get seriously interested in control making a few years ago. I have done home electrical systems for several years. Built a food elevator and a few automated things. But I'm still a noob at this. My neighbor just asked me to have a look at his machine for cloth making.

So basically the first machine has 2 magnetic contacters inside. When you plug the machine up the first contacter gets energized.

When you press the green button the 2nd contacter energizes and the machine turns on.

Problem is it turns off when you release the green button. I don't know if it's a latching push button switch that's broken or if it's wired so that the contactor will latch after pressing the button.

It's all single phase.

Next machine the green push button does nothing. It's doesn't engage the 2nd contacter.

 

Just had a thought about it, if it was a latching push button, you would have to press it again to break the circuit and you wouldn't need a stop button, so obviously its wired to latch but wired incorrectly. So i just need to make a diagram of how its wired, find the fault.

 

Unless the wiring was intentionally changed, it probably isn't wrong. What is more likely is that something broke or a wire came off/got disconnected. Having a wiring diagram will be very helpful.

 

Sat down for an hour in front of the machine and worked out where each wire went and what it went to. Used a multimeter and a tester and bypassed the contacts that were giving me trouble and it's working fine now.

 

It seems like the first machine's green button might be a momentary switch, causing the second contactor to disengage when released. Check if it's a latching switch or if the wiring configures it as such. For the second machine, verify the button's functionality and the wiring to the second contactor. A continuity test might help identify any faults. By the way, did you find something?

 

Thanks for the Reply @PaulPittman. Yes I got it working. Just worked out where each wire was going and used a multimeter to test for continuity. It seemed some of the contactor contacts weren't working but I got it rewired and its working fine.