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> how relay works ?
jimkelly
post Nov 6 2013, 06:02 AM
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and can some describe how a relay works?

is it that HIGH AMPERAGE thru 85 and 86 operate a switch, and when switched send LOW AMPERAGE thru 30 and 87? what is 87A's purpose?


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arcadeforever
post Nov 6 2013, 06:49 AM
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from what I can see.... oddly enough it appears 87a has no purpose, its a pole for whatever event 85 and 86 do to 30 that make 30 switch to 87 (85,86 could be the grid for a rear defroster system(just a wild guess)). Im not sure WHY 87a has nothing hooked to it. I guess Id have to see the rest of the schematic.

this is a SPST (Single Pole Single throw) switch/relay. relays have tons of applications, this is a pretty smart relay where the sensor within the relay switches the load, typically, what they pretty much do is use a low power circuit to turn on a high power circuit. A relay in a fog light scenario, where, when two terminals are connected via a switch will actuate a high current switch that turns on the lights.

You cant eliminate the relay in this type of circuit or you will watch the switch in your dash melt into a puddle (IMG:style_emoticons/default/smile.gif) The relays' high current contacts are made of MUCH thicker metal so it can handle the current/heat.

The double relay for the FI system is an amazing little relay that gets switched on when the key turns to on and ALSO has a set of inputs from the AFM that turn on the fuel pump, so basically the fuel pump gets turned on with the AFM is actuated meaning the engine is creating vacuum. Of course it does more than that...
QUOTE(jimkelly @ Nov 6 2013, 07:02 AM) *

and can some describe how a relay works?

is it that HIGH AMPERAGE thru 85 and 86 operate a switch, and when switched send LOW AMPERAGE thru 30 and 87? what is 87A's purpose?
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arcadeforever
post Nov 6 2013, 07:21 AM
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Shows how much of a newb I am, lol, I just saw in another post that this is one of the relays on the relay board. Im sure I will grow to know them (IMG:style_emoticons/default/smile.gif)
QUOTE(arcadeforever @ Nov 6 2013, 07:49 AM) *

from what I can see.... oddly enough it appears 87a has no purpose, its a pole for whatever event 85 and 86 do to 30 that make 30 switch to 87 (85,86 could be the grid for a rear defroster system(just a wild guess)). Im not sure WHY 87a has nothing hooked to it. I guess Id have to see the rest of the schematic.

this is a SPST (Single Pole Single throw) switch/relay. relays have tons of applications, this is a pretty smart relay where the sensor within the relay switches the load, typically, what they pretty much do is use a low power circuit to turn on a high power circuit. A relay in a fog light scenario, where, when two terminals are connected via a switch will actuate a high current switch that turns on the lights.

You cant eliminate the relay in this type of circuit or you will watch the switch in your dash melt into a puddle (IMG:style_emoticons/default/smile.gif) The relays' high current contacts are made of MUCH thicker metal so it can handle the current/heat.

The double relay for the FI system is an amazing little relay that gets switched on when the key turns to on and ALSO has a set of inputs from the AFM that turn on the fuel pump, so basically the fuel pump gets turned on with the AFM is actuated meaning the engine is creating vacuum. Of course it does more than that...
QUOTE(jimkelly @ Nov 6 2013, 07:02 AM) *

and can some describe how a relay works?

is it that HIGH AMPERAGE thru 85 and 86 operate a switch, and when switched send LOW AMPERAGE thru 30 and 87? what is 87A's purpose?


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Posts in this topic
jimkelly   how relay works ?   Nov 6 2013, 06:02 AM
914itis   How relay works Have fun   Nov 6 2013, 06:29 AM
arcadeforever   wow, thats a great document! How relay works H...   Nov 6 2013, 06:54 AM
JStroud   How relay works Have fun Nice link, where did y...   Nov 6 2013, 08:44 AM
914itis   [quote name='914itis' post='1952680' date='Nov 6 ...   Nov 6 2013, 10:32 AM
arcadeforever   from what I can see.... oddly enough it appears 87...   Nov 6 2013, 06:49 AM
arcadeforever   Shows how much of a newb I am, lol, I just saw in ...   Nov 6 2013, 07:21 AM
pcar916   To answer in short... When the circuit is comple...   Nov 6 2013, 07:57 AM
pcar916   Bowlsby has a lot of information on his site. htt...   Nov 6 2013, 09:54 AM
Dave_Darling   I also have a write-up, about halfway down in this...   Nov 6 2013, 10:02 AM
pcar916   Forgot about this! That's a great write-up...   Nov 6 2013, 10:07 AM
jimkelly   freakin ingenious. since our cars are run from a...   Nov 6 2013, 10:50 AM
Spoke   freakin ingenious. since our cars are run from ...   Nov 6 2013, 11:53 AM
pcar916   ... i think image is correct? 30 is always a pe...   Nov 7 2013, 03:19 AM
underdog   ... i think image is correct? 30 is always a p...   Nov 7 2013, 07:52 AM
Dave_Darling   30 is always a permanent ground. No, 30 should be...   Nov 7 2013, 09:43 AM
Mike Bellis   Current is limited by the fuse size and to some ex...   Nov 6 2013, 11:41 AM
Mike Bellis   By the way current is stupid and don't know sh...   Nov 6 2013, 11:47 AM
Tom   Relays use a small current to control a much large...   Nov 6 2013, 01:09 PM
r_towle   Current or load is always dictated by the device c...   Nov 6 2013, 05:32 PM
Mike Bellis   Read this...   Nov 6 2013, 08:00 PM
jimkelly   I believe pin 30 is always connected to either 87 ...   Nov 7 2013, 08:41 AM
Spoke   I believe pin 30 is always connected to either 87...   Nov 7 2013, 09:25 AM
Mike Bellis   Relay nomenclature: 30: Common 87: Nomally Open 87...   Nov 7 2013, 09:56 AM


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