Jump to content

voltage drop when load is applied with HO alternator


Recommended Posts

So when the current is drawn at 2k rpm, the alternator becomes more resistant( harder to spin) and that's when belt slip happens?

Yep.

In the most simplest sense, the alternator turns kinetic energy into electrical energy. If there's no load (a completed circuit) then there's nothing for the alternator to do physically. The more load you put on it, the more kinetic energy it is converting into electrical energy. The belt slips if the alt is trying to convert more kinetic energy than the belt can give.

And about the wire supplying current to your window motors... when the wire is small, there will be more voltage drop as the motor tries to pull current through. The result is more current is consumed but lost in the wire as heat, and voltage drop.

But hey, this is all theory ;)

2007 Pacifica
Rebuild. Less quiet. Still not loud.

Link to comment
Share on other sites

Positive probe to your alt charging post, negative probe to alt casing. Then measure your voltage drop with a multi meter.

Throw an amp in there, put a non-stock load on it and see how the alt reacts.

Who makes your alt?

It's a Singer Alternator which was tested and is 100% functional.

I'm looking around now to buy amp so once I'll get it I'll give it a shot.

Link to comment
Share on other sites

If your belt was slipping you'd see a bunch of black powdery rubber crap on the alt

Link to comment
Share on other sites

I haven't seen any rubber or noise coming from the engine (squeaking noise). Over the weekend I will test the voltage at the alternator and in the back at the battery.

Just trying to fix this issue ASAP. Driving without a bass for more that a year is getting really annoying.

Link to comment
Share on other sites

But if the belt was slipping, wouldn't the voltage be all over the place?

no, it would act as if it were running at a slower RPM.

2007 Pacifica
Rebuild. Less quiet. Still not loud.

Link to comment
Share on other sites

So I did little testing.

When I turn the heater on, headlights on, voltage goes down to 13.4-13.7 @2k rpm. When I roll the windows, it dips down even lower to around 13.2-13.4(but only for a brief second). Same reading at the front positive terminal, in the back where battery.

I also used a power converter as outside load and plugged a small TV in and the voltage didn't go below 13.4-13.7 with the TV on and @2k rpms. I don't know how much TV draws, but power converter is rated up to 1000watts.

Link to comment
Share on other sites

Did another test.

Hooked up converter with a vacuum cleaner which draws 800 watts. When I turn it on, the voltage would dip down to 13.1-13.3 volts and then climb back up to 13.9-14V and stay there with a vacuum on.

So I'm guessing when the load hits the alternator it slips, but then catching the grip???

Link to comment
Share on other sites

I'm not sure why you are so worried. Everything you describe is completely normal. If its bothering you that much, get an AVBM and that should solve your issues.

truthsayer

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Who's Online   0 Members, 0 Anonymous, 1325 Guests (See full list)

    • There are no registered users currently online
×
×
  • Create New...