My plant has a lot of 20yo machines from Germany, which use pushbuttons by Schneider Electric. Everything mostly runs fine, but I'm noticing that none of the NC contact blocks are 0 ohms across the 2 pins. I'm getting between 500-3k ohms across just the button's contact block. Should I be concerned? Especially for the Estop buttons? Where should I draw the line for replacing "lossy" buttons?
My Estop circuit is 24Vdc going through 7 lossy NC estop buttons, accross maybe 200 feet of wire, to a contactor (probably 20V dropout voltage). A legitimate or illegitimate Estop trips out the contactor, and kills power to all motors. (Contactor turns on only after a special reset procedure is performed.)
I am getting only 22V by the time it goes back to the contactor coil. I accept that there will be some voltage loss, but from a make/break pushbutton? Should I replace all my estop buttons with another brand? (I was thinking automationdirect, since I have a more than 300 estop buttons in the plant.)
Like I said, everything runs right now, despite being lossy. The Estop buttons will open the estop circuit when pushed. The concern for me right now is preventing illegitimate estops. Just wondering what I should do? How severe is the need to replace these buttons? And in general, what is an acceptable amount of loss accross a NC pushbutton contact block, before you would replace it?
My Estop circuit is 24Vdc going through 7 lossy NC estop buttons, accross maybe 200 feet of wire, to a contactor (probably 20V dropout voltage). A legitimate or illegitimate Estop trips out the contactor, and kills power to all motors. (Contactor turns on only after a special reset procedure is performed.)
I am getting only 22V by the time it goes back to the contactor coil. I accept that there will be some voltage loss, but from a make/break pushbutton? Should I replace all my estop buttons with another brand? (I was thinking automationdirect, since I have a more than 300 estop buttons in the plant.)
Like I said, everything runs right now, despite being lossy. The Estop buttons will open the estop circuit when pushed. The concern for me right now is preventing illegitimate estops. Just wondering what I should do? How severe is the need to replace these buttons? And in general, what is an acceptable amount of loss accross a NC pushbutton contact block, before you would replace it?