There are 1000 volts available but no amps. Should there be?

It will be assumed that a 1000 volt primary supply is connected to the primary of a resistance welding transformer. The question is should this produce amperage on the secondary? Assuming that the control is functioning, wiring is correct and the transformer is good the answer is yes. There should be voltage and current at the transformer secondary terminals. The amount depends upon the equipment.

Transformer Construction rev

This means that many items need to be verified to insure that all is correct. If all is correct and there is no voltage and current present at the secondary, back up the circuit and test.

Is there voltage at the primary?

Is the transformer grounded properly? If the transformer is failing to ground it should have tripped a breaker. In either case investigate the transformer.

Is there a properly sized breaker on the system?

If the transformer is good, move up a level.

Then back up another lever head to the control etc. Check all connections and fuses. The control could be failing and not activating the SCR. A component has failed or is wired improperly somewhere. Search till it is found.

A conductor, fuse, component has failed somewhere in the system. A 1000 volt connection will flow if connected and the components are functioning properly.


Reference: RWMA - Resistance Welding Manual 4th Edition
                   AWS - J1.2 Guide to Installation and Maintenance of Resistance Welding Machines 

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