REQ: coil volatage on old relay

Use an ohm-meter to find the coil connections. Use a variable psu. The point where the relay engagess is usually around half the rated voltage.

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Kind regards,
Gerard Bok

I have a bunch of old Potter & Brumfield ones. They are all 24VDC.

You might try this. Use a variable dc power supply. Connect to the coil leads at zero volts. Increase the voltage until the armature moves. This is the pull-in voltage. Write it down. Now drop the voltage and wait until the armature drops down. this is the drop-out voltage. Now add the drop-out voltage to the pull-in voltage. Then go to the nearest highest value that makes sense, like 5V, 6V, 12V, 24V, 48v... this could then be used as your coil rating. Run it at that voltage for a while. Monitor the current and the temp. If it doesn't run away, you're good.

Al

dig, dig,

Don't open it up, it looks like it's a Mercury Wetted relay. Have not found that exact number yet.

Clare became part of General Instrument sometime back then, And since then sold off.

The one page I found with specs shows a wide range of voltage drive. A minimum voltage given as a "Must Opr. VDC", and a "Max VDC". For the HG2A1003, it's 15 and 36 volts, respectivly.

Yow, $87.10 back in 1986.

Mark Zenier snipped-for-privacy@eskimo.com Googleproofaddress(account:mzenier provider:eskimo domain:com)

snipped-for-privacy@eskimo.com (Mark Zenier) wrote in news:f63875$v95$ snipped-for-privacy@eskinews.eskimo.com:

Hi Mark-

That's an affirmative on your last- the relay is a mercury wetted contact type, which is why I want to use it- I need to switch some milliamp level

9VDC signals. Coil is pins 7 & 8. I can bench test it as others have suggested if necessary, but would like to know what Clare/General Instruments had to say if possible, esp. if the coil is AC or DC.

Have had the relay for decades- no clue where I originally came up with it- prob. Mil. surplus somewhere.

Thanks for your help.

Regards,

Cap'n John