Relay help :)

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mole
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Location: Kent

Relay help :)

Post by mole »

Can anybody help me find out what terminal is what on the relay I found in the garage. I want to use it for my fogs.

Here is the diagram on the side of the relay.

Image

Cheers
polo2k
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Post by polo2k »

ok ill describe the diagram for everyones benifit because i was looking for somthing similar the other day :D
30, 87 & 87a are your secondary contacts so this would be your fogs for example you connect a permanant live to 30 and then depending if you want the fogs to turn off or on with the primary current you go to eith 87 or 87a
87 is NO meaning that when the relay is in its dormant state no power to the primary contacts there is no conti nuity between 30 and 87 but 87a is always in contact until the primary contacts are energised

the big box is the electro magnet that is powered by contacts 35 and 86 which in turn operates the secondary contacts
so to wire up your fogs you would earth contact 35 and then feed the power from your interior switch to 86. then connect a permanant live to terminal 30 and the power wire into the fogs to 87
this would mean that when you activate the interior switch the electromagnet gets charged attracting the rocker within the relay in turn bringing contacts 30 and 87 into contact

ps the little box at the bottom is either a resistor or prolly a diode which helps to prevent damage to other components when the relay is deactivated as a simple relay can send a reverse voltage spike as the movment around the coil can induct a little charge into the primary curcuit (still cant spell )
for reference the primary contacts (35 and 86) are the low current side
and the secondary contacts (30, 87, 87a) are the high current contacts
the principle of a relay is that a low current handleing component can drive a large consumtion component.
i hope that all made sence if it didnt please post and tell me how to explain better
mole
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Location: Kent

Post by mole »

Yep got that all, cheers mate :)

Got my fogs today so needed to sort a relay ready for fitting them :D

Cheers again, mole.
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