Relay operation question....
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From: Canada (NCR)
Relay operation question....
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the relay on the left is how I learned to wire a relay.(the posative is not a circut still under "load" by a light or something...it is something like the old posative connection to a headlight that is no longer used to power the headlight..it is used as a trigger, like my hid setup)
I was wondering if the method on the right will work?? can you have a relay 'trigger" on a circut that has a light bulb on the end...and the bulb will still work??? (the light bulb is ovousley grounded, I just frogot to draw that)
If this does not make sence I can explaine it better
the relay on the left is how I learned to wire a relay.(the posative is not a circut still under "load" by a light or something...it is something like the old posative connection to a headlight that is no longer used to power the headlight..it is used as a trigger, like my hid setup)
I was wondering if the method on the right will work?? can you have a relay 'trigger" on a circut that has a light bulb on the end...and the bulb will still work??? (the light bulb is ovousley grounded, I just frogot to draw that)
If this does not make sence I can explaine it better
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From: Canada (NCR)
yup, need a new circut and there is one allready loaded to the max near where I need the new circut.
so I wonder if I can use this circut that is maxed and I do not want to put anything more on as a "trigger" for my new circut. The old "trigger" circut is a swiched 12V and I need my new circut to be switched as well
puttin a auto dimming mirror form a Diville in the 90
puttin a auto dimming mirror form a Diville in the 90
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First things first. It's "positive"....
Next: The left side is the low-power side of teh relay. The right side is the high-power side. If you have a device that requires a lot of current, put it on the right side and use the left side to switch it on.
If you have a device that can be run off the low current on the left side, just use a switch and not a relay.
In your right-hand diagram the light bulb would be like an indicator light to tell you whatever high-current device is attached to the high-power side is turned on.
If you have a device that can be run off the low current on the left side, just use a switch and not a relay.
In your right-hand diagram the light bulb would be like an indicator light to tell you whatever high-current device is attached to the high-power side is turned on.
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Re: First things first. It's "positive"....
what I need is to use the switched 12V that powers my guages to also turn on and off a new rear view mirror that I am going to wire in. I can not just use the power from the guages as it is allready runnung a few other things.
I want to run a new power to the rear view mirror that I am putting in...and have it turn on and off with the switched 12V, so.. I was wondering if the signal (+) from the guages lights could be used as the "trigger" for the rear view mirror via a relay???
hope that makes sence
I want to run a new power to the rear view mirror that I am putting in...and have it turn on and off with the switched 12V, so.. I was wondering if the signal (+) from the guages lights could be used as the "trigger" for the rear view mirror via a relay???
hope that makes sence
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Can always use the relay to trigger another relay with another power source.
If your wiring won't support the load that is. Most automotive SPST relays will support 30A IF the wiring on terminals 87/87A/30 will support that load. Many automotive relays will actually handle 40A. If you need more than that, switch to a solenoid. They have cont. duty solenoids from Cole Hersee and Stancor (White-Rogers) that will allow for a constant 200A draw. A solenoid would act in the same way as a relay, as they coil and a set of contacts.
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Instead of relay #1 terminal 86 (or 85) going to ground, have it go to terminal 85 (or 86) on relay
#2. Your switched load power source can then be taken from any other 12v circuit that is either key-on or always-on.
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ok so let me see if I understand... like this??
kinda like a "daisy chain" ?
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