AuroraGirl
I'm Awesome
powermaster CS130D is different than what we were talking aboutt, a built CS130. CS130D is in the problem AD230 has, and if you are going to do that, you would just make sense to upgrade to AD230 and skip cs130d
Can the 120 amp optional alternator drop right in if you have the 105 amp standard?
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AuroraGirl
I'm Awesome
The thing he was trying to convey is that there is little benefit or accuracy to using a DVOM , flukes even, to ohm something on those scales. Ohm a switch or a small wire? sure.
but with a alternator charge wire, doing a voltage drop test and getting then a small result .1-.2 I think...? would be fine.
If you did it for your charge wire or junction perhaps even from the charge wire(Idk whats on the truck off top head) and you got something big, that means connections and cables need looking at
On the case of alternator, you should be able to get readings especially ground. there is an acceptable limit
On the alternator per gm with CS130s on a 3800, here is an egghead saying
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(the voltage drop taken on the alternator grounding bracket and the battery negative)
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This alternator is grounded to the bracket, bracket to engine, engine to cable all the way over by starter on block (so the head, intake, are in the path too), then cable to gm side post (pew)
He said anythign less than half a volt would be fine.
If you runs your engine and do this kind of test, you will see ground changing and stuff, but hopefully it stays ok. i recommend checking cables individually and doing end to far end, for example, doing that for your battery positive and the farthest junction or whatever , or alt charge output stud etc.
Voltage drop is helpful and you shouldnt see a lot but you will see some.
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heres a theoretical system here. if you wanted to expand your horizons after confirming things are ok, you can use your voltage sense wire. the cool thing is what ever you wire it to directly with one continuous wire, your system will maintain the charging system to the predetermined (14.5 ish) AT that spot.
so if you had a lot of voltage drop on your power cables but you made sure your, saym offroad lighting fuse box or winch , your truck wouldnt bog down much when those are on, be brighter/fasteer and the engine controls shouldnt swing much etc
Then, you need to see what that damn brakcet be up to
So I replaced it this morning with a new NAPA unit. It charges wonderfully, but I've lost the radio and have a ton of alternator whine through the speakers. Radio fuse is good and that's as far as I'm going today with it.
Oh joy.
Bad diode in the bridge? Noisy / erratically operating regulator?
F-it. Take it back and exchange.
Good stuff here, I'll reply to various segments:
Exactly. Those meters weren't designed to measure milliohms using their "Ohms" resistance capability.
Yes, but (of course) this is best done when carrying high load in the conductor (e.g., 100A thereabouts). Measuring under no- or low-load isn't really the objective. Measurements can be done not only to the charge wire but any significant wire, e.g., ground lead to battery, ground strap(s), power lead to the fuse block, fuel pump power and ground, headlight power and ground, etc. When in doubt about how heavily the conductor's loaded, I'll measure using a DVM (to get the voltage drop in the conductor) and a DC current clamp (to get the current flow); from these one can determine, in general, whether there's a concern and, if useful, the resistance (R = V/I) of the conductor.
Defining "big" would help here. "Big" to me is, generally, a voltage drop of .3V or less when under the heaviest load for that conductor. That's "generally". I would tune that number up or down in specific situations.
Yes, that's not a bad example, but I don't know if that picture was taken under load. 0.03V would be very good IMHO if the current in that ground lead was 100A.
I've said "under load, .3V" or less. If greater, think about the situation and whether improvement is possible (my not be) and beneficial (if not, don't bother).
Yup. Use the alternator's "voltage sense" option carefully. It's a neat feature but if used without care it can cause large voltages in the wrong place.
Example: In my K1500 the alternator (B+) lead runs to the battery and then continues on (across the radiator) to the driver's side fuse block. I've considering running a "voltage sense" wire from that fuse block connection back to the ALT, but it could be a bad idea. Why? If large loads are present at the fuse block and cause notable voltage drop in that conductor (~1V say), the voltage at the battery will be higher than optimal; if the loads are present for a long period of time, the higher voltage at the battery puts it under duress.
Given the above example, I might consider connecting the "voltage sense" wire to the battery (B+) terminal and call it done.
But the take-away is, this feature can be a double-edge sword.
$0.02
Exactly. Those meters weren't designed to measure milliohms using their "Ohms" resistance capability.
Yes, but (of course) this is best done when carrying high load in the conductor (e.g., 100A thereabouts). Measuring under no- or low-load isn't really the objective. Measurements can be done not only to the charge wire but any significant wire, e.g., ground lead to battery, ground strap(s), power lead to the fuse block, fuel pump power and ground, headlight power and ground, etc. When in doubt about how heavily the conductor's loaded, I'll measure using a DVM (to get the voltage drop in the conductor) and a DC current clamp (to get the current flow); from these one can determine, in general, whether there's a concern and, if useful, the resistance (R = V/I) of the conductor.
Defining "big" would help here. "Big" to me is, generally, a voltage drop of .3V or less when under the heaviest load for that conductor. That's "generally". I would tune that number up or down in specific situations.
Yes, that's not a bad example, but I don't know if that picture was taken under load. 0.03V would be very good IMHO if the current in that ground lead was 100A.
In the case of 100A... sure, OK, allowable but could do better by a few tenths... if one really wants / needs the incremental improvement that, say, 0.2V might bring (which isn't much but could make the difference in a few, atypical situations).
I'm not exactly sure what you mean by this, "ground changing" and what's meant by "stays OK", but I'll let it slide unless you want to comment.
Yes... No... I would do it from cable endpoint to cable endpoint, unless... if the cable has a connector in its midpoint, I would measure twice (treating it as though it was two cables, effectively).
OK, I cry fowl. How much is "a lot" and how much is "some"?
I've said "under load, .3V" or less. If greater, think about the situation and whether improvement is possible (my not be) and beneficial (if not, don't bother).
Yup. Use the alternator's "voltage sense" option carefully. It's a neat feature but if used without care it can cause large voltages in the wrong place.
Example: In my K1500 the alternator (B+) lead runs to the battery and then continues on (across the radiator) to the driver's side fuse block. I've considering running a "voltage sense" wire from that fuse block connection back to the ALT, but it could be a bad idea. Why? If large loads are present at the fuse block and cause notable voltage drop in that conductor (~1V say), the voltage at the battery will be higher than optimal; if the loads are present for a long period of time, the higher voltage at the battery puts it under duress.
Given the above example, I might consider connecting the "voltage sense" wire to the battery (B+) terminal and call it done.
But the take-away is, this feature can be a double-edge sword.
$0.02
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Voltage drop testing is enormously more useful/accurate than testing resistance on most any automotive circuit with a wire harness set up for more than a few amperes.
As you might expect, for almost all circuits, the less VD the better.
Starter and alternators in particular require VD testing. For forty years, I've use 1/2 volt of VD on starter circuits, and 1/4 volt on charging circuits as practical maximums when the circuit is LOADED (Starter motor cranking; alternator at or near max. output.)
I've been stung (once...) by resistance testing a low-resistance circuit when I failed to take the 0.2-ohm meter lead resistance into account. After "zeroing" the meter with the leads included, I got reasonable test results.
As you might expect, for almost all circuits, the less VD the better.
Starter and alternators in particular require VD testing. For forty years, I've use 1/2 volt of VD on starter circuits, and 1/4 volt on charging circuits as practical maximums when the circuit is LOADED (Starter motor cranking; alternator at or near max. output.)
I've been stung (once...) by resistance testing a low-resistance circuit when I failed to take the 0.2-ohm meter lead resistance into account. After "zeroing" the meter with the leads included, I got reasonable test results.
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AuroraGirl
I'm Awesome
oh boy.Good stuff here, I'll reply to various segments:
Exactly. Those meters weren't designed to measure milliohms using their "Ohms" resistance feature.
Yes, but (of course) this best done when carrying high load (e.g., 100A thereabouts). Measuring under no- or low-load isn't really the objective. This should be done not only to the charge wire but any significant wire, e.g., ground lead to battery, ground strap(s), fuel pump grounds, headlight grounds, etc. When I question, I'll measure each using a DVM (to get the voltage drop in the conductor) and a current clamp (to get the current flow); from these one can determine the resistance (R = V/I) and, in general, whether there's a concern in that circuit.
Defining "big" would help here. "Big" to me is, generally, a voltage drop of .3V or less when under the heaviest load for that conductor. That's "generally". I would tune that number up or down in specific situations.
Yes, that's not a bad example, but I don't know if that picture was taken under load. 0.03V would be very good IMHO if the current in that ground lead was 100A.
In the case of 100A... sure, OK, allowable but could do better by a few tenths... if one really wants / needs the incremental improvement that, say, 0.2V might bring (which isn't much but could make the difference in a few, atypical situations).
I'm not exactly sure what you mean by this, "ground changing" and what's meant by "stays OK", but I'll let it slide unless you want to comment.
Yes... No... I would do it from cable endpoint to cable endpoint, unless... if the cable has a connector in its midpoint, I would measure twice (treating it as though it was two cables, effectively).
OK, I cry fowl. How much is "a lot" and how much is "some"?
I've said "under load, .3V" or less. If greater, think about the situation and whether improvement is possible (my not be) and beneficial (if not, don't bother).
Yup. Use the alternator's "voltage sense" option carefully. It's a neat feature but if used without care it can cause large voltages in the wrong place.
Example: In my K1500 the alternator (B+) lead runs to the battery and then continues on (across the radiator) to the driver's side fuse block. I've considering running a "voltage sense" wire from that fuse block connection back to the ALT, but it could be a bad idea. Why? If large loads are present at the fuse block and cause notable voltage drop in that conductor (~1V say), the voltage at the battery will be higher than optimal; if the loads are present for a long period of time, the higher voltage at the battery puts it under duress.
Given the above example, I might consider connecting the "voltage sense" wire to the battery (B+) terminal and call it done.
But the take-away is, this feature can be a double-edge sword.
$0.02
So when I showed the pic, his reading is from the starter turning the over, cs130 dont disable for crank like later ones, so the load was a 5mt or SD250 i think they decided to call the old direct drive starters
The PG260 is gear reduction but you know what im saying. Also the end point yes, but I dont know off top of my head how the power wires look at on the truck so I said it wonky more car oriented.
When I say ground change, ti would not be constant, the reading would fluctuate. if you had a power window using engine ground because the frame to battery sucked dick youd probably see things here there everywhere
also on battery sense, ive heard to the starter is a good idea. forget why. if your charge cable isnt got bad drop itself its almost useless to run the wire but it still can pick up on demand change quicker than the internally wired to the stud
AuroraGirl
I'm Awesome
Good stuff here, I'll reply to various segments:
Exactly. Those meters weren't designed to measure milliohms using their "Ohms" resistance capability.
Yes, but (of course) this is best done when carrying high load in the conductor (e.g., 100A thereabouts). Measuring under no- or low-load isn't really the objective. Measurements can be done not only to the charge wire but any significant wire, e.g., ground lead to battery, ground strap(s), power lead to the fuse block, fuel pump power and ground, headlight power and ground, etc. When in doubt about how heavily the conductor's loaded, I'll measure using a DVM (to get the voltage drop in the conductor) and a DC current clamp (to get the current flow); from these one can determine, in general, whether there's a concern and, if useful, the resistance (R = V/I) of the conductor.
Defining "big" would help here. "Big" to me is, generally, a voltage drop of .3V or less when under the heaviest load for that conductor. That's "generally". I would tune that number up or down in specific situations.
Yes, that's not a bad example, but I don't know if that picture was taken under load. 0.03V would be very good IMHO if the current in that ground lead was 100A.
In the case of 100A... sure, OK, allowable but could do better by a few tenths... if one really wants / needs the incremental improvement that, say, 0.2V might bring (which isn't much but could make the difference in a few, atypical situations).
I'm not exactly sure what you mean by this, "ground changing" and what's meant by "stays OK", but I'll let it slide unless you want to comment.
Yes... No... I would do it from cable endpoint to cable endpoint, unless... if the cable has a connector in its midpoint, I would measure twice (treating it as though it was two cables, effectively).
OK, I cry fowl. How much is "a lot" and how much is "some"?
I've said "under load, .3V" or less. If greater, think about the situation and whether improvement is possible (my not be) and beneficial (if not, don't bother).
Yup. Use the alternator's "voltage sense" option carefully. It's a neat feature but if used without care it can cause large voltages in the wrong place.
Example: In my K1500 the alternator (B+) lead runs to the battery and then continues on (across the radiator) to the driver's side fuse block. I've considering running a "voltage sense" wire from that fuse block connection back to the ALT, but it could be a bad idea. Why? If large loads are present at the fuse block and cause notable voltage drop in that conductor (~1V say), the voltage at the battery will be higher than optimal; if the loads are present for a long period of time, the higher voltage at the battery puts it under duress.
Given the above example, I might consider connecting the "voltage sense" wire to the battery (B+) terminal and call it done.
But the take-away is, this feature can be a double-edge sword.
$0.02
lets do some ground credibiiltiy checks
Well in that case I'll take it back to NAPA in the morning. I guess I'll find out what their return process looks like.
lets do some ground credibiiltiy checks
Yes... "When is a ground not a ground?"
In "mains wiring", sure, there's a "ground rod" in the ground... that's the ground. The other conductors are designated appropriately... L1, L2, Neutral, etc.
Why's it called "ground" in an automotive application?
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