View Full Version : blown fuse

Fishin LCO
05-31-2004, 01:24 PM
I need a little help. I think these may be a simple solution I can fix if not I will tell my customer to see an irrigation specialist. Here is the problem. The control panel flashes PR Off, which I assumes means power off. I looked into it and found it was the fuse blown in the box I replaced it and ran the all the zones manually and it work fine. Well it happened again, so I replaced the fuse again. I worked again, but blew the fuse once again. I am thinking it blows the fuse when it cuts on automatically. Is this a bad connections somewhere, bad ground, bad relay or what? Thanks for any help.

05-31-2004, 02:06 PM
What kind of controller is this? Rainbird? Hunter? If it's Rainbird LX series, and the fuse is blowing whenever it wants to run a cycle, it's becasue of a faulty transformer. Get a replacement for it and it should take care of the problem.

05-31-2004, 02:25 PM
One single solenoid or wire could be blowing the fuse... What I would do (may or may not be the most efficient method but works for me) replace the fuse.... go through the zones manually until the fuse blows... when you find out what zone is blowing the fuse find that valve in the valve box.... when you find that valve cut the wires going into the solenoid... if you replace the fuse and go through that zone again without the fuse blowing then it's the solenoid... replace the solenoid... this method will cost you either one or two fuses

05-31-2004, 03:21 PM
Might not hurt to remove the common wire at the controller and check the resistance for each zone. I'll bet you'll find it. If they are fine use the multi tester to see what the AC is at the transformer, but I'll be its in the field wiring.

Fishin LCO
05-31-2004, 07:00 PM
BSME, you were right on the money. I really appreaciate the help. thank you everyone. yall are the best

06-01-2004, 05:23 PM
BSME is right. However we occasionally find solinoids that ohm out normal but still don't work or work properly popping fuses. It is called an intermittent open. Same thing can happen in a car battery. simple volt test looks normal but won't crank. In both cases the electrical load causes a break down of continuity in some time frame of useage.

A load tester will find the defective battery. In irrigation don't be afraid to swap the solinoid as in this case even though it ohms OK.