Have back feed on 115 volt control line. need to control it so it will not pull in coil on relay?

back feed is 67volts to 89 volts. have put in resistors up to 247k stops one relay but not othersHave back feed on 115 volt control line. need to control it so it will not pull in coil on relay?
Try putting a lower resistance in parallel with the coil. If its bad enough you could distribute resistance along the line or put another low resistance close to the source.





This is one of those things you have to play around with. When adding resistance at the end of the run you have to take into account the ampacity of the control cable. You can't put a resistor in that will allow more current than the cable is good for. Since its also a probably a pretty long run of cable you need to consider voltage drop along the cable if you were to put a low resistance at the relay coil.





Can you change out the relay for one with a lower impedance?








Just curious but how long is the cable run?





I saw this one time at the plant I work for. The cable run was very long. I don't remember just how long but I'm wanting to say it was around 4000'. We solved this one by putting another relay that had a lower impedance in parallel with the relay that was operating.Have back feed on 115 volt control line. need to control it so it will not pull in coil on relay?
I suspect you have '; stray-voltage '; that might be induced onto this control circuit by adjacent power cables that may be laying together with this circuit ? If the relay's circuit control cable is armoured, make sure it is glanded %26amp; grounded properly at one end. Other wise, see if it is possible to lay new control cables for the relay or it circuit ? Good Luck
I don't see how induced voltage from nearby lines can induce enough power to activate a relay. I don't know what kind of relays these are, but I suspect it takes watts to activate them, and cross coupling is usually much smaller than that. Unless we are dealing with miles of wires.
You can now try putting resistance in parallel to the relay coil. in addition to series resistance. Give me feedback.