volt or amp gauge

[Tony Smith]

Cab 11 used a brown faced "Batt" meter. While not a true Voltmeter, they read approximate battery voltages from 5V to 9V. These voltages are not marked on the gauge, only bands of red, orange and green to indicate safe levels. Lower red band was up to 6.2v, orange from 6.2v to 7.1v, green was 7.1v to 8.25v, upper red was above 8.25v.

Ford only used these from '40 to '41. Cab 12 changed to a brown faced Amp meter, Cab 13 had a grey faced Amp meter.

The Batt meter can be modified to work on a 12V system and show the correct bands of voltage ranges from 10V to 14V. You cannot use a regular voltage converter for other gauges, as these will just output a constant 6.8v and will peg the needle in the orange band irrespective of the electrical system's condition (until your 12V battery drops below 6.8V!) Note that the Batt meter is polarity sensitive, some vehicles are Pos earth, some are Neg earth.

The Amp meter is an induction coil with a wire simply passing trough loop on the back of the gauge. This will work unmodified on a 12V system, but only in a -40A to +40A range. This is fine for a Generator system, but most Alternators will exceed this range.

[Dave Schindel]

Hi Tony, the panel in your pic is identical to the one in my cab 11 "parts" truck. I for now am assuming that the gauges with amp meters are from civilian trucks.As you said, the amp meter had the induction coil , and I suppose I could modify the wiring system to accommodate that without too much trouble. Thanks for the reply,Dave

[Tony Smith]

Originally Posted by Dave Schindel

I for now am assuming that the gauges with amp meters are from civilian trucks.

Originally Posted by Tony Smith

Cab 12 changed to a brown faced Amp meter, Cab 13 had a grey faced Amp meter.

Dave, the instrument clusters with Amp gauges could still be from CMP's, just later models.

[Dave Schindel]

oops,thanks for the correction,and all the info Tony.
cheers,Dave

[rob love]

I have only seen voltmeters with the commercial panels used in CMP vehicles. My newer Ford manuals are at work...I'll check and see what they list tomorrow.

[Dave Schindel]

OK, thanks Rob