What's behind these grouphead bolts??
If this machine is quite old then I am thinking that the problem could be back EMF. It's common practice in DC circuits to use some diodes on the solenoid coil to counter this problem.
It makes some sense ( to me only perhaps) when the group is switched off the solenoid coil creates back EMF while the magnetic field collapses, which may be enough to trip the RCD. If you think it's plausible then an oscilloscope could tell you.
If this machine is quite old then I am thinking that the problem could be back EMF. It's common practice in DC circuits to use some diodes on the solenoid coil to counter this problem.
It makes some sense ( to me only perhaps) when the group is switched off the solenoid coil creates back EMF while the magnetic field collapses, which may be enough to trip the RCD. If you think it's plausible then an oscilloscope could tell you.

Comment