Amp draw of coil based relays

Automotive relays are typically 150-200mA ("72 ohm coil").

Smallish reed relays with 12V coils are in the 12mA range. ("1K ohm coil").

As I hint above, relay specs are typically given in coil resistance.

Tim.

Reply to
Tim Shoppa
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Depends on what you mean by small, but small power relays (eg. a few A) typically consume in the hundreds of mW (eg. 360mW). At 12V, that's

30mA. You can probaby find some in the 100mA range. Generally, coil power goes up with switching current, lifetime and voltage isolation, so relays made to more stringent European safety standards tend to use a bit more power.

Best regards, Spehro Pefhany

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"it\'s the network..."                          "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
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Reply to
Spehro Pefhany

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Potter and Brumfield T7NS5D1-12

http://relays.tycoelectronics.com/datasheets/T7N_DS.pdf
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Reply to
John Fields

Does anyone have any idea as to how many milliamps do small coil based relays (12v coil) draw, typically?

i
Reply to
Ignoramus21666

If you know the make an model you can look it up

Or

You can measure the coil resistance with an ohm meter and calculate it

Dan

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Dan Hollands
1120 S Creek Dr
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Reply to
Dan Hollands

Thanks, Spehro, Tim, and Dan.

I am trying to buy some cheap relays to let my kid play with his toy LifeLike railroad.

He is very much into traffic lights and this railroad.

For example, if a train approaches a RR traffic light, and it is red or yellow, stop the train. If a train approaches a crossing, light red light on the crossing. Etc. It should be very easy with a 12v power supply and some relays and alligator clips, and maybe light switches or some such.

We already have a power supply, traffic light etc.

So, I am looking to buy some cheap 12v coil relays. Hence my question.

i
Reply to
Ignoramus21666

Thanks, that's good stuff. I will try to find something like that for less on ebay, if not, I will buy some new ones.

i
Reply to
Ignoramus21666

Thanks. I bought some 50 Sigma 12v 4 pole SPDT relays at 60 cents apiece on ebay... I hope that they should work fine. The power supply has quite a bit of extra power available after powering the toy train, so amp draw of coils should not be a huge issue.

i
Reply to
Ignoramus21666

On Tue, 06 Dec 2005 17:59:03 GMT, Ignoramus21666 wrote in Msg.

Datasheets and ammeters usually have pretty good ideas about how much current things draw.

robert

Reply to
Robert Latest

and little kids have fairly good ideas of how to wreck ammeters :) But I quite agree, it would be the thing to get for them.

NT

Reply to
meow2222

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