Power Distribution Box 2005 PSD & "resting" current draw

[etbadger]

Originally Posted by IheartDieselVans

I ask him how he's measuring it and he says that he dropped the batteries and disconnected ONE negative terminal and has got his meter between the negative battery terminal and he clamp. I very gently remind him that there are two batteries in parallel, and that perhaps the other batt is now being drawn. No, he says, this is how they've always done it.

He is wrong, you are right. With a meter between only a single battery and ground that battery will contribute less than 1/2 the current draw (presuming identical batteries) due to the resistance of the meter shunt.

If that is how they have always done it for dual battery systems then they have always done it wrong.

-e

[Skywagon]

Erik-
It's nice to see you back on the Forum- You can always be counted on for good and detailed information.
Bill

[IheartDieselVans]

etbadger,

That's what I thought, seems obvious even given my limited training in electronics. I'm dealing with Larry Miller Ford in Salt Lake City...does anyone have advice about how I should proceed? I feel really strange about correcting a tech on their technique, especially if it's their standard practice. But if it's wrong, it's wrong. I've done a considerable amount of altering to this van, including a Fibrine top, 4x4 conversion, and a house battery system. I have not tied it in to the stock vehicle electrical system yet though, it's still completely separate.

While the vehicle is still under the bumper to bumper warranty, with many years left on the PSD warranty, I know that not all dealers want to honor the warranty when so much has been done to the vehicle, specifically the 4x4 conversion...so I don't want to piss anyone off.

I thought of talking with the service manager, but imagine that if he's not technically inclined he might just go with what they've always done.

Any ideas would be appreciated.

Oh, and I edited this to say THANKS to everyone for the great information on this site, I've found it extremely useful in my modest home build. Specifically, THANKS a ton to the Badgers, your documentation of your van build and modifications are a HUGE help. Cheers!

[IheartDieselVans]

I just spent a little while measuring power draw under various conditions, and thought I'd post them here for posterity. My method was to place my multimeter between the black common ground and the frame, without breaking continuity in the process.

Some background, I've got a super fancy Eclipse stereo with backup camera, satellite radio, and a big touch screen. I added a switch to the yellow B+ wire, so I can choose between drawing power from the vehicle start batteries (stock set up) or my auxiliary bank. The red wire (ACC) is as it was, connected to the key-on power.

Resting parasitic draw, not driven for 12+ hours: 0.21amps
Resting draw with a door open: 0.45 amps
FM radio playing, medium volume: 2.5a
Satellite radio playing, same volume: 3.2a

Key in ACC position, radio power switched to Aux batteries: 0.43amps

Hope that is helpful to somebody someday!