Battery voltages

[bbyer]

Five files on the PWM alternator.

Near the top of the link below are five files related to the Pulse Width Modulated alternator and "internal regulator" that is in our 3's - and yes, they are Denso designed alternators. While the problem is solved, I figured you might want to know a bit more about the electrical charging system.

http://www.**************/gallery/thumbnails.php?album=3801

Replace the **** with disco3 co uk and insert a period in each of the two spaces.

 

[GSMblue]

UPDATE:

I have had the new alternator in for about 2 weeks. The voltage at idle has been 13.5v and the battery voltage with the engine off has been 12.0-12.5v

There is some squealing, much worse when the engine is cold.... Yesterday it was soooo bad my wife complained... so back to the garage...

Sure enough they say there is some wear on the belts. I am surprised they did not change the belts when they did the $1300 worth of work on the alternator.... The garage said there were no cracks on the belts so they re-used them.

I have asked them to change the tensioner at the same time another $350...

Hopefully this will be the end of the issue, for a while!

 

[newthings]

My wife squeals in the morning also. Good luck.
Cheers, Roy

 

[Disco Mike]

13.5 is at the very low end of our required needs, 14 to 14.4 is where a new alternator should be.

 

[GSMblue]

Thanks Mike, that is what I thought.... What can I do about this? Should the garage change it out?

 

[Disco Mike]

I would have them replace the alternator under warranty.

 

[drivesafe]

UPDATE:

I have had the new alternator in for about 2 weeks. The voltage at idle has been 13.5v and the battery voltage with the engine off has been 12.0-12.5v

Hi GSMblue and you need to measure the voltage while you are driving.

My D3 often had 13.45v at idle but this can be caused by the high operating current the D3’s electrics use and a low battery.

I monitored my D3 for months while developed some new gear for it.

You need to set up a means to have a voltage display in the cab and then you will see what the operating voltage really is.

As far as your battery voltage goes, the voltage of a battery that has been sitting for at least 10 hours since the motor was last on, will give you a reasonable idea of the actual state of charge of the battery.

The chart below will give you some idea of the state of your battery.

Note, you can have a battery with a low voltage reading if you are only doing short drives.

If this is your normal use of the D3, then you are better off waiting till you have been on a long drive and then measure the battery the next morning. You will then see whether you battery is holding it’s charge or not being charged.