The answer applies to any brand of digital kiln. There are two situations: The kiln shuts off because the circuit breaker trips, or the controller’s display goes blank but the circuit breaker does not trip.
CIRCUIT BREAKER TRIPS
To turn on the heating elements, the controller sends a signal to one or more relays. They, in turn, send power to the elements. When the circuit breaker trips right after you press the Start button, unplug the kiln and remove the kiln’s switch box. Look for an electrical short on the element side of the relay:
1) A relay-to-element lead wire is touching the heat shield. Find the two element connectors for each element. You will see wires attached to the connectors. Look for a wire with frayed insulation that is touching the kiln case. Also, check the wire terminals. If one is tilted far enough to touch the heat shield, it can shut off the breaker. Look for a small burn mark on the heat shield. It is a sign of electrical arcing between the wire terminal and the heat shield.
2) Place an ohmmeter probe on an element connector and the other probe on the kiln case. The ohmmeter should show no continuity.
3) Look for a disconnected element-to-relay wire that is touching the kiln case.
4) It is possible for element pins from two adjacent elements to touch each other inside the firebrick wall. This causes the elements to short out between each other. This will cause an ohmmeter reading that is much lower than normal for those elements.
DISPLAY GOES BLANK BUT CIRCUIT BREAKER DOES NOT TRIP
1) A defective relay is drawing too much current from the controller, making the display go blank. Unplug the kiln. Disconnect the two controller-to-relay wires from each relay, one at a time. (In Paragon kilns, they are the red and black wires.) Position the disconnected wires so that the wire terminals cannot touch each other or anything else inside the switch box. After you disconnect each relay, turn the kiln on again and press the Start button. Do this until you find the relay that is draining the controller. Replace that relay.
2) The transformer that powers the controller is wired incorrectly or is going bad. Study your kiln’s wiring diagram to make sure the transformer is wired properly.