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MG TD TF 1500 - Ammeter Reading

I put the clamp on ammeter around various wires and after fluttering a bit I get the reading that looks like .0L (point zero "Ell").

I could not find an explanation in the manual.

Does this have some common meaning that I am unaware of?
Mort

Mort Resnicoff

Hi

Over Load, try going up a range from 2A?

Barry
B Bridgens

Sheer guesses, absolutely no knowledge - 0ver Load, and/or rest of zeroing the machine (? ?).

If so you could try resetting the zero and testing on a known quantity to confirm calibration (within the tool's tolerances).
Nigel Atkins

Thank you

Upon retesting and changing scales I realize that it does mean overload.
Mort Resnicoff

Hi Mort,
"Ol" means Overload on usual electronic measurement equipment.
Current from or to battery is often above 2 A. Even 20 A scale could be overloaded. Try first with the 100 A scale and then lower the scale if the reading is to low.
Clamping ampmeter needs to be zeroed before measurement with no current (no wire) through the clamp. Then clamp only one wire of the dashboard ampmeter to get the measurement.

Laurent.
LC Laurent31

The "squiggle" means AC amperage I believe, won't read DC.

My thoughts.

Peter
P G Gilvarry

Don't want to get to far OT hijack Mort's thread but I notice that his clamp ammeter indicates that it can measure both AC and DC current. It's too cold and too much snow on the ground here in sunny South Carolina to go up to the shop and see if mine says the same but I've often wondered if a clamp (induction?) ammeter can read DC current. It appears the answer is "Yes" but please confirm. Thanks.

Jud
J. K. Chapin

I once tested the draw on my starter cable with a clamp ammeter and it read -105. Ignition on car not running was -2.8. Engine running at 1800RPM +10 but this would vary with the state of the battery? Are these figures reasonable?
John Quilter (TD8986)

Mort's meter's display says 'DC'. Mine is labeled as being ambidextrous:
Bud

Bud Krueger

Peter, Bud,

I don't know this meter, but I think that it will measure DC current. The blue button seems like the mode selector.


John
J Scragg

Yes it does read both AC & DC.

And yes the blue button is the selector.

Thank you all for the input.

Now I am off to visit the underside of my dash.

Ugh!

Mort
Mort Resnicoff

I just recently got a chance to work on the car.
This is a copy of the email I sent to the manufacturer.
Thoughts appreciated.

The attached schematic shows my current wiring.
It does not appear that the Dynamator is charging the battery.
I would very much appreciate your analysis.

I have the Dynamator installed.

When I activate the battery cutoff switch I get a negative reading on the ammeter of about 4.5 amps.
I get this reading with the clamp on ammeter between the ammeter and the cutoff switch and between the ammeter and the Dynamator.
I get no reading on the jumper from the ammeter to the ignition switch.

When I start the car the ammeter stays negative until I pass about 2500 RPM.
Below 2500 RPM it returns to a negative reading.

The system is not charging the battery.




Mort Resnicoff



Place a VOLT meter between the output of the alternator and ground.
You should read over 13 volts, closer to 14.5 in the winter if the alternator is working.

Jim B.
JA Benjamin

This thread was discussed between 13/12/2018 and 20/12/2018

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