How to test a relay?

[mikay786]

Trying to figure out if this relay is bad, every video I watch online is car related and they all look way diiferent.

Relay is a EMI-SH-212D - http://www.rapidonline.com/electroni...-relay-60-4640

8Pin



I have tested resistance on the first two pins which I believe is the coil and resistance is 358 Ohms, which I believe is in spec according to the datasheet.

That's as far as I have got. One thing I have noticed is when I shake it there is something rattling inside. Is that a sign of a bad relay?

[stj]

Re: How to test a relay?

it should never rattle, anything loose could jam it.

that asside, if you meter the 4 center pins to check the off-resistance,
then power the coil from a battery and check the on-resistance of the right 4 contacts - is how you test one.

[mikay786]

Re: How to test a relay?

Definetly think something was wrong with the relay, as after taking it out and shaking it I put it back in and the unit (subwoofer) is powering up. Before it was blowing fuses.

So when shaking it something must have clicked into place or whatever. Ordered a replacement from here: http://www.technobotsonline.com/rela...i-ss-212d.html

Slight difference model number as is EMI-SS-212D instead of the original EMI-SH-212D, but I think they are the same?

Sorry struggling bit understanding.

not powered
read resistance between pin 4+6
read resistance between pin 3+5

powered by 12v batter on pins 1+2
read resistance between pin 6+8
read resistance between pin 5+7

[joshnz]

Re: How to test a relay?

with relay un-powered check resistance
between 4 and 6 then 3 and 5

with relay powered check resistance
between 6 and 8 then 5 and 7

[mikay786]

Re: How to test a relay?

I've accidentally broken a smd cap, just to make sure as in not sure is this a 1uf 50v cap?

And can I just use a regular leaded cap to replace?

[stj]

Re: How to test a relay?

yes.

[mikay786]

Re: How to test a relay?

Cheers