"Button 22/23 is an emergency stop. Directly after the emergency stop in the circuit there is a normally closed stop button. When pressing the button 12/13, contactor 1 and 3 are powered. This in turn powers light 10/11 and 18/19 while disabling contactors 2 and 4. By pressing the button 14/15, contactors 2 and 4 are powered. The normally closed gates in the branches of contactor 1 and 3 open, disabling those lights and contactors, while the lights 16/17 and 20/21 receive power. To reset circuit, press red button 6/7."
I designed the attach schematic to fit the above circuit description. I understand that our schematic drawings are different than most and am not sure why, but they are simple. The rectangles are contactors and the switches will have be numbered "K---" depending on which contactor the switch is on. There are normally closed and normally open. The circles with the X are lights and there are also buttons, 12/13, 6/7 and so forth.
My problem is that the second contactor chatters when I try to press the second button. Pressing the second button should turn off the first and third so that the second and forth can turn on but this doesn't happen. It only chatters. I can press the normally closed reset button 6/7 and then press the second button to turn on contactors 2 and 4 with their respective lights and vice versa. I'm taking it this means that the first and third contactors don't shut off so the second and fourth can turn on. I went through and tested continuity to make sure I wired it correctly and it appears to be good. When doing my voltage check, I found that when contactor 2 was activated with the second button, normally closed 71/72 and 62 of K2 all had a serious voltage drop from 120 to 6 or less. I'm not sure how to fix this or what the problem could be since my continuity check tells me that everything is wired correctly. My instructor said my schematic should work if correctly wired but didn't pay much mind to it so he could have been wrong. Will the schematic drawn function according to the description? If it should, what could be my problem? The only descrepencies I found were the aforementioned voltage drops with the normally closed switches. Thanks for your help!
I designed the attach schematic to fit the above circuit description. I understand that our schematic drawings are different than most and am not sure why, but they are simple. The rectangles are contactors and the switches will have be numbered "K---" depending on which contactor the switch is on. There are normally closed and normally open. The circles with the X are lights and there are also buttons, 12/13, 6/7 and so forth.
My problem is that the second contactor chatters when I try to press the second button. Pressing the second button should turn off the first and third so that the second and forth can turn on but this doesn't happen. It only chatters. I can press the normally closed reset button 6/7 and then press the second button to turn on contactors 2 and 4 with their respective lights and vice versa. I'm taking it this means that the first and third contactors don't shut off so the second and fourth can turn on. I went through and tested continuity to make sure I wired it correctly and it appears to be good. When doing my voltage check, I found that when contactor 2 was activated with the second button, normally closed 71/72 and 62 of K2 all had a serious voltage drop from 120 to 6 or less. I'm not sure how to fix this or what the problem could be since my continuity check tells me that everything is wired correctly. My instructor said my schematic should work if correctly wired but didn't pay much mind to it so he could have been wrong. Will the schematic drawn function according to the description? If it should, what could be my problem? The only descrepencies I found were the aforementioned voltage drops with the normally closed switches. Thanks for your help!
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