I was trying to test a relay today in the shop with a multimeter and I had it set to continuity to see if the coil was good and nothing happened even though the relay activated when I put power to it manually. I am fairly new at this but not totaly lost. the was a resistance or diode on it and I cut it to see if it would do something and still nothing. If I tap the relay it will get continuity going through it. what is going on?
Check Pins 85 and 86 for continuity. Then put 12v on them and see if it works. If your meter is set too low it may not read the resistance.
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John DeRosa (Hotwaterwizard)
Stockton California
When in doubt, try it out !
I did check pin 85 and 86 and there was no continuity untill i hit the relay the I get continuity. My meter is set at audible continuity sysmbol looks like this )))) If I switch my multimeter to diode test which looks like ->|- then it will beep. why does it beep on that setting and also why does continuity begin after i hit the relay?
Sounds like a bad relay to me.
I did some research on relay resistance for you and here are some of the results i got so far.
12VDC/30A SPST Automotive Relay Brand: RadioShack
Catalog #: 275-226 Model: 275-226
Coil Rating: 12VDC, 160mA, 400 ohms
12V SPDT 30 AMP AUTOMOTIVE RELAY
Sting Pro # RL-5X. 12 Vdc, 88 ohm coil.
N.O. contacts rated 30 A. N.C. contacts rated 20 amps
https://www.allelectronics.com/cgi-bin/category.cgi?item=RLY-351
12V AUTOMOTIVE RELAY: Has 30A SPDT Contacts with 73ohm relay coil.
These are the standard size
Omron Special purpose automotive relay
High power 70A relay
Standard ISO terminal footprint
Contact Form SPST
Contact Type Single
Max Switching Current 70A
Rated Voltage 12VDC
Coil resistance 65 ohms
OKO Relay 12vdc 40 amp contacts coil resistance 90 0hms
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John DeRosa (Hotwaterwizard)
Stockton California
When in doubt, try it out !