GOVTMOD's dumb electrical question of the day; solenoid "I" post as power source?
#1
GOVTMOD's dumb electrical question of the day; solenoid "I" post as power source?
I'm putting a power control box in my truck with a key on relay.
I figured it would be OK to hook up the relay to the "I" post of the solenoid. The box is going pretty much where the solenoid is right now and I'll in turn be relocating that down the fender shirt but it will still be right there.
I just wanted to check if there would be any issues. If there are, where would be the best place to hook it up? I'd rather not have to run it all the way from the ignition switch.
I figured it would be OK to hook up the relay to the "I" post of the solenoid. The box is going pretty much where the solenoid is right now and I'll in turn be relocating that down the fender shirt but it will still be right there.
I just wanted to check if there would be any issues. If there are, where would be the best place to hook it up? I'd rather not have to run it all the way from the ignition switch.
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So, I understand you want to run a signal wire to the "I" post of the starter solenoid to engage the relay (a continuous duty solenoid) of the power distribution box, right? It'll work.
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#8
The S terminal is for "Start" and is energized by the ignition switch.... Or am I reading these schematics incorrectly?
#9
Hello GOVTMOD,
Yes, the fan and headlights relays need to be fused.
Hello HIO Silver,
Yes, the 'I' terminal can be connected directly to the + post on the coil, and will only have current at start up.
This connection is for ignition systems with ballast resistors, or resistor wire, whereby the voltage to the coil is +/- 9 volts, but at start up, the coil needs +/- 12 volts.
Yes, the fan and headlights relays need to be fused.
Hello HIO Silver,
Yes, the 'I' terminal can be connected directly to the + post on the coil, and will only have current at start up.
This connection is for ignition systems with ballast resistors, or resistor wire, whereby the voltage to the coil is +/- 9 volts, but at start up, the coil needs +/- 12 volts.
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Thats not true, unless its a latching relay, a standard automotive relay requires current to stay on to keep the relay switched.
#13
You guys aren't going to make me go out and check myself are you? There's like 6" of snow out there, no joke and it's not letting up. No room in the garage either.
Seriously, I do appreciate the input even if it is contradictory. I do know that I don't have to have a full 12v to run the relay as I've actually been testing them with a 9v battery. The terminals are spaced perfectly for 85 & 86. I do need to find out if it is actually hot with the key at "on" and whether it will cause problems anywhere else if I borrow the current.
Seriously, I do appreciate the input even if it is contradictory. I do know that I don't have to have a full 12v to run the relay as I've actually been testing them with a 9v battery. The terminals are spaced perfectly for 85 & 86. I do need to find out if it is actually hot with the key at "on" and whether it will cause problems anywhere else if I borrow the current.
#14
You guys aren't going to make me go out and check myself are you? There's like 6" of snow out there, no joke and it's not letting up. No room in the garage either.
Seriously, I do appreciate the input even if it is contradictory. I do know that I don't have to have a full 12v to run the relay as I've actually been testing them with a 9v battery. The terminals are spaced perfectly for 85 & 86. I do need to find out if it is actually hot with the key at "on" and whether it will cause problems anywhere else if I borrow the current.
Seriously, I do appreciate the input even if it is contradictory. I do know that I don't have to have a full 12v to run the relay as I've actually been testing them with a 9v battery. The terminals are spaced perfectly for 85 & 86. I do need to find out if it is actually hot with the key at "on" and whether it will cause problems anywhere else if I borrow the current.
The "I" terminal on the starter solenoid is hot ONLY when the key is in the start position. It is dead when the key is in run.
The "I" terminal shoots a full 12V to the coil when starting. When you release the key and it returns to the run position the "I" terminal will be dead.
If you need a constant 12v source when the key is in the run position, the "I" terminal will not work.
EDIT: Thinking about it . The "I" terminal will have voltage to it when the key is released but I wouldn't recomend using it as a power tap.
When you release the key the circuit inside the solenoid opens and stops feeding 12v to the coil, BUT the circuit will now backfeed FROM the coil. It will only be ~6-7 volts though AND it will place an additional load on the ignition circuit, something that generally isn't desired as it could lead to mis-fire or other ignition problems .
#15
That sucks about the snow, glad I'm in Fla.
The "I" terminal on the starter solenoid is hot ONLY when the key is in the start position. It is dead when the key is in run.
The "I" terminal shoots a full 12V to the coil when starting. When you release the key and it returns to the run position the "I" terminal will be dead.
If you need a constant 12v source when the key is in the run position, the "I" terminal will not work.
EDIT: Thinking about it . The "I" terminal will have voltage to it when the key is released but I wouldn't recomend using it as a power tap.
When you release the key the circuit inside the solenoid opens and stops feeding 12v to the coil, BUT the circuit will now backfeed FROM the coil. It will only be ~6-7 volts though AND it will place an additional load on the ignition circuit, something that generally isn't desired as it could lead to mis-fire or other ignition problems .
The "I" terminal on the starter solenoid is hot ONLY when the key is in the start position. It is dead when the key is in run.
The "I" terminal shoots a full 12V to the coil when starting. When you release the key and it returns to the run position the "I" terminal will be dead.
If you need a constant 12v source when the key is in the run position, the "I" terminal will not work.
EDIT: Thinking about it . The "I" terminal will have voltage to it when the key is released but I wouldn't recomend using it as a power tap.
When you release the key the circuit inside the solenoid opens and stops feeding 12v to the coil, BUT the circuit will now backfeed FROM the coil. It will only be ~6-7 volts though AND it will place an additional load on the ignition circuit, something that generally isn't desired as it could lead to mis-fire or other ignition problems .