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ArTurf
07-14-2012, 06:14 PM
The relay makes a REALLY loud buzzing noise when a station is turned on and the pump does not turn on. This definitely is not a normal electrical buzz. It is more like the contactor rapidly closing and opening, almost violently. Any thoughts?

1idejim
07-14-2012, 06:22 PM
The relay makes a REALLY loud buzzing noise when a station is turned on and the pump does not turn on. This definitely is not a normal electrical buzz. It is more like the contactor rapidly closing and opening, almost violently. Any thoughts?

measurements?
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ArTurf
07-14-2012, 06:39 PM
measurements?
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I didn't have any irrigation tools with me at the time. Just wanted to get some opinions before I go back to the site.

Duekster
07-14-2012, 06:44 PM
contactor is not pulling in. Did you do a screw driver test? Be careful you could die if not experiance in testing contactors like this.

ArTurf
07-14-2012, 06:49 PM
contactor is not pulling in. Did you do a screw driver test? Be careful you could die if not experiance in testing contactors like this.

I understand how contactors work but I'm not familiar with the screwdriver test. Can you describe. What are you trying to determine?

Duekster
07-14-2012, 06:58 PM
I force the contactor in to see if if the pump / EQ runs.

Not the best method but short of meters, it is a quick and potentially dangerious test.

Wet_Boots
07-14-2012, 07:20 PM
If the pump breaker/disconnect can be accessed, maybe remove power from the pump, and see what the contactor does.

jvanvliet
07-15-2012, 07:49 AM
I agree with Duekster; probably the contact is chattering; check all your connections including the ones from the breaker and the controller.

Out of curiosity, what type of relay is it? I've had problems like this with Hunter pump start relays.

ArTurf
07-15-2012, 01:34 PM
I agree with Duekster; probably the contact is chattering; check all your connections including the ones from the breaker and the controller.

Out of curiosity, what type of relay is it? I've had problems like this with Hunter pump start relays.

It is a homemade one from basic electrical components. I will go back to site Monday and check it out.

1idejim
07-15-2012, 01:37 PM
It is a homemade one from basic electrical components. I will go back to site Monday and check it out.

Be careful and wear gloves Arthur
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Duekster
07-15-2012, 01:39 PM
I wired in a 480 3 phase contactor hot one time.

It was on a lead/lag vacuum pumps system in a hospital.

I was sweating bullets. No need to take chances.

1idejim
07-15-2012, 02:03 PM
I wired in a 480 3 phase contactor hot one time.

It was on a lead/lag vacuum pumps system in a hospital.

I was sweating bullets. No need to take chances.

i have 25kva gloves but that doesn't mean i bare hand 12.5 wire.

what i do, i do pretty well. what i don't do well i leave alone.
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jvanvliet
07-15-2012, 07:15 PM
It is a homemade one from basic electrical components. I will go back to site Monday and check it out.

Geez... :dizzy:

jvanvliet
07-15-2012, 07:17 PM
I wired in a 480 3 phase contactor hot one time.

It was on a lead/lag vacuum pumps system in a hospital.

I was sweating bullets. No need to take chances.

No brain no pain eh?

Duekster
07-15-2012, 07:38 PM
No brain no pain eh?

It was kind of an emergency... one of many I had as a young man fresh out of school and placed as a Chief Engineer in a hospital. Too many sleepless nights.

I should tell you about the night we ran out of oxygen, or the night we lost heat....Lost most my hair in a short 6 month before I decided to walk.

ArTurf
07-16-2012, 06:29 PM
Went back today and took readings. Readings checked out OK, the contacts seemed to be burned and I noticed a small spring in the bottom of the box. So I decided to replace the contactor. After pulling the old one out I realized the spring was 1 of 2 that held the contacts apart. Everything working fine now.

Duekster
07-16-2012, 06:52 PM
Went back today and took readings. Readings checked out OK, the contacts seemed to be burned and I noticed a small spring in the bottom of the box. So I decided to replace the contactor. After pulling the old one out I realized the spring was 1 of 2 that held the contacts apart. Everything working fine now.

Cool. Happy it worked out.
Do you have a megger to check the pump motor windings.

Often these contactor issues develop over time and can cause some over heating that will weaken motor windings. I would only worry about it if you want to be preventive.