Alternator good signal, how many amps is it good for without FSSSST! (1 Viewer)

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Does anyone have "actual" specifications of the alternator good signal coming from the alternator. This is the Orange/Black stripe wire which is coming from the regulator "unfused"
I want to know if anyone has a FSM that details the regulator and/or gives regulator specifications/circuitry.
I want to use it for a few different relays and need to know if I can hang 2 amps off it or more or less without blowing the crap out of the regulator, or for that matter draining the alt good signal so it actually affects the regulation characteristics of the regulator or the longevity of it.
I know it has been used to power small relays in dual battery situations, but I am chasing specifics if possible.
Thanks in advance
100 TD
 

Lka1988

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I used it to power my headlights directly, until I decided that it wasn't a good idea (about a week). Still fine.
 

alia176

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A thing to do is to use the CHG 7.5A fuse in the engine bay to run your own IGN relay. You can run all kinds of stuff from this relay, such as the dual battery 200 amp mondo relay.
 
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Why not just use it to power a small relay, then use the relay to power your other loads?

Well yes, what I want to do is power a few relays etc. I don't want relays powering relays, I would also fuse the take off circuit at 5 amps or lower, but I feel the output of this wire is very low and if over drained may affect the regulator. The FSM I have does not go into it at all, I was hoping someone may have come across an explanation of the reg and outputs in an older FSM as they are giving you less and less info each year.
 
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A thing to do is to use the CHG 7.5A fuse in the engine bay to run your own IGN relay. You can run all kinds of stuff from this relay, such as the dual battery 200 amp mondo relay.

I don't have a CHG fuse, but have a ALT-S (alternator sense) fuse, however all fuses are powered directly or by the IGN or ACC switch, I don't want an IGN circuit, I want an ALT GOOD circuit.
 
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I have never seen a reference for the current capacity alternator good signal on an 80 series, much less an out of market diesel 100 series, It only purpose is to drive a small light bulb use beyond that current level is anyones guess,

becasue of problems I wound up using a very small realy to power a solenoid, something I wrote in a previous thread.

In the original plan the wire that feeds the mini relay’s coil was suppose to go direct to the solenoid, but there was an electrical noise problem generated by the coil optimizer in the 9012 (PWM circuit) that added noise on AM radio on top of my pre existing engine noise on AM.

Talked to Wane @ Blue Sea I asked about the frequency of the PWM circuit, he did not know, did find out that the peak current of the square wave is 0.4a and average around 0.13a, he first recommended a 330 μF (micro farad) capacitor alone to reduce the electrical noise, I asked about using diodes or resistors to help and he said a choke would help but not really needed, being all about overkill in went the choke along with the capacitor to make a full filter, The choke tends toward leveling the current; the capacitor tends to level the voltage. that was revision 1, noise gone.

But now the alternator good signal would drop to 2v when it tried to close the solenoid and it never closed, I think the added inrush of the capacitor (very short but can be high) pissed off the IC in the alternator, so I had to take the burden off the IC with the mini relay. Revision 2 everything works

I have no idea how much current the alternator good signal can safely provide, after seeing Slee power a solenoid and 3 relay’s on his figured I was safe. Apparently not. Draw on the IC is now only 0.030A just the coil of the mini relay.

been a couple of years now and as you could probably guess that tiny .03A load has been no problem
 
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Here is some useful info on this; however, just as RavenTai mentions, finding actual specs on the regulator is almost a no win problem. U could measure current thru the bulb with ur handy Fluke meter; that would give u an idea of the drain figured into the design.

AUTOMOTIVE TECHNICAL ARTICLES

We will have a test on Friday!!

...
 
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A shot in the dark here, if you are trying to be sure your add on relays shut down incase of a alternator failure use should know that the sometimes Denso regulators do fail in such a way that it mat output the voltage to turn off the battery lite but not charge the battery. Some time its simpler to either watch the voltmeter or install a add on volteeter with a adjustable low voltage warning output.

J
 
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A thing to do is to use the CHG 7.5A fuse in the engine bay to run your own IGN relay. You can run all kinds of stuff from this relay, such as the dual battery 200 amp mondo relay.
This is most likely the same as the ALT good signal, if it only energises after the engine is running and the alternator is working. Otherwise it is probably the same as the "sense" 7.5 amp fuse on mine which has power when IGN is on.

Ahh, my bad...I'm not familiar with your vehicle.
Same same, just a later model, IIRC very little has changed between the models.

I have never seen a reference for the current capacity alternator good signal on an 80 series, much less an out of market diesel 100 series, It only purpose is to drive a small light bulb use beyond that current level is anyones guess, becasue of problems I wound up using a very small realy to power a solenoid, something I wrote in a previous thread. been a couple of years now and as you could probably guess that tiny .03A load has been no problem
Yes I may use a SSR for low current and drive some other relays (i didn't want to though)
T

Here is some useful info on this; however, just as RavenTai mentions, finding actual specs on the regulator is almost a no win problem. U could measure current thru the bulb with ur handy Fluke meter; that would give u an idea of the drain figured into the design.

AUTOMOTIVE TECHNICAL ARTICLES

We will have a test on Friday!!

...
he dash indicator is now switched by the body ECU! The ECU obviously gets an input from the ALT GOOD SIGNAL and switches an output to the lamp, so not a direct current consumption anymore.
The tech artical has the older style diagram, more like what the 80 would have I expect. However id does explain the regulator partially which is good. I might sniff around some of the other subjects as well!

A shot in the dark here, if you are trying to be sure your add on relays shut down incase of a alternator failure use should know that the sometimes Denso regulators do fail in such a way that it mat output the voltage to turn off the battery lite but not charge the battery. Some time its simpler to either watch the voltmeter or install a add on volteeter with a adjustable low voltage warning output.

J
Hopefully the ALT GOOD SIGNAL will do, yes I have seen lamps working with minimal output etc.

Thanks everybody.
 
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This is most likely the same as the ALT good signal,.


one and the same,

There is no body module on the 80, the low no charge lamp has + from the IGN fuse on one side and + from the IC regulator on the other through the 7.5 charge fuse, if the regulator is not making power it becomes a ground and power flows from the ign fuse through the light the charge fuse and then the regulator, giving the amber no charge lamp.
 

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