Ammeter installation

Can I remote wire a second ammeter via my existing meter in the dash, run the second meter in parallel with the first.

If it’s a shunt type ammeter, no you cannot just parallel in another meter.

High Wire said:

If it’s a shunt type ammeter, no you cannot just parallel in another meter.

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I disagree. As long as it's just adding the meter and not the shunt. The meter itself is just measuring millivolts. Adding another voltmeter in parallel should not change things much.

You may lose a small amount of accuracy due to the extra leads and 2nd meter resistance, but it should not be much. Better quality meters will have less influence.

JMHO

Agreed. The very high impedance of a second meter should have very little impact on the meter reading. This can be easily tested by temporarily connecting the second meter right at the shunt while a second person observes the other meter.


Ken

Hmmm I am unsure if this analogue meter has an internal shunt, just two small terminals on the back one marked with a -.
Is there any way to check if it has a shunt.
I have tried paralleling it over the back of the existing gauge (alternating off both terminals) with no result. If I disconnect the wires from the back of the existing gauge/meter and attach them to the analogue meter it works fine!!!
Is this any help with my problem

If the analogue meter does prove to have an internal shunt how can I wire it into the charge circuit as the wires are very light!!

Not being great on electrics, why piggy-back a second to the same location - wouldn't the readings be identical?

menzies said:

Not being great on electrics, why piggy-back a second to the same location - wouldn't the readings be identical?

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I can understand his desire to parallel a 2nd meter. Perhaps to the fly bridge?

I have considered putting a 2nd, parallel meter in the galley so I can be careful while I am cooking on the electric stove/oven/microwave.
Right now, when the 120vt light goes dark, time to reset a breaker. With the amp meter, I can manage the stove more carefully.

Based upon a previous experience, yes you may see a discrepancy between the 2 meters but not enough to worry about.

One thing I did not try was to use a larger wire to the remote meter to see if the discrepancy disappears.

An internal shunt would not be able to deal with more than a couple of amps. There are several ways to tell. If the wires to the ammeter are thin, it is really a voltmeter measuring the voltage drop in millivolts across an external shunt. You can also check the impedance of the "ammeter". Just measure resistance across its terminals. If it is close to zero, it has an internal shunt and should only be used for very low amperages and you cannot parallel it. However, if its resistance is > 10 kilo ohm, it is really a voltmeter and can be attached in parallel to the existing one. Of course, the second ammeter should be identical to the first or match the external shunt specs (e.g. same millivolts per amps)