I have a CNC Router Parts Nema 23 control w/ESS.  this system uses a toroidal transformer, 2 x 115vac primary with 28v Ac 8amp and 8v Ac 2amp secondary's. when i power up the machine the 2amp fuse after the transformer and bridge rectifier keeps blowing, this is the side that powers the proximity sensors. i cant find any loose or broken or grounded wires. this happened 2 years ago when i moved the machine and i simply replaced the 2amp fuse and been running fine. well, i just moved again and this time the fuse blew again and the problem is here to stay. i am desperate for help as this is how i make my living and the support team at avid cnc only want to sell me a new control system, very frustated. thank you in advance, Dan
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was not sure where to post this. thank you

Hi,
disconnect all the prox sensors from the power supply, and hook them up one at a time until you find the dud one.

Craig

joe, i actually already did that. the fuse blows upon initial power up with all sensors unplugged. i also removed all 5 of the sensor receptacles and cleaned and checked for loose/broken wires. it has to be something that was affected by the physical move, again. thank you for your reply

problem solved. last week i bench tested the capacitors and resistor/diode combos and apparently assembled the diode backwards. i then found a faulty wire barely hanging on on the circuit that had been failing. i was sure i found the problem but the fuse still failed because diode being backwards. another round of retesting those components found the issue with the diode...put it back the way it should be and presto!
i believe the initial problem was the faulty wire but i only found it after i had created another problem. hope this helps someone. thanks again joe average!