This is a board that controls a circular knitting machine, this machine has 108 MPF feeders, those feeders controls 108 yarn, when a yarn breaks the feeder lights its bulb the machine decelerates to stop, at this moment, the worker must fix the yarn and run the machine again, I want to take 2 wires from somewhere to activate a relay when the switch of one or more is closed I want to use this relay to operate a bulb I'll put it on the top of the machine so the worker can see it easily and come to fix the yarn again:
please see the pictures below:
This question contains a unique parts which differentiate it from my other question, I'am asking for the function of the components in this circuit and how can I benefit from them.
Best Answer
Here's the circuit diagram based on my interpretation of the photographs.
U 1520 is a 15A diode. When the switch is closed the optocoupler in TLP 504A would be turned on and would shut-down the machine through a relay.
The circuit diagram may be verified for its correctness.
A relay driver circuit is shown below.