Field Circuit Resistance(Ohms) Test Worksheet
This is a test of the field wiring attached to the controller. This test guides you though the process of measuring the ohms resistance in the field wiring through each zone. Using the guidelines below determine if each circuit/zone is good or bad.
Step 1.--Disconnect the common field wire(s) from the common terminal on the controller.
Step 2.--Set your multimeter to a Resistance range of 0 to 100 ohms.
Step 3.--Hold one lead against the bare wire on the common wire. With the other lead touch the terminals of the controller one by one. Mark down on this sheet the Resistance(ohms) with the corresponding zones.
Rule of Thumb:
0-6 ohms -- a shorted circuit-bad solenoid or shorted wiring
6-12 ohms -- a slow burn solenoid or Asco solenoid
12-20 ohms -- normal/possible two solenoids on circuit or an Asco solenoid connected on circuit
20-60 ohms --Normal operating range
60 ohms + -- open circuit
Those circuits which fall in the Normal range are good circuits. The rest need to have thesolenoids and field wiring tested separately. Follow the Field Test Flow Chart to find the problem.
© Control Tech USA, Inc 2005