24 Volt Displaying weird amp readings

My Selene 53 is having an electrical issue. Looking at the breaker panel it shows the amp meter bouncing from a plus 15 amps or so to a fluctuating minus. -136.6 is an example. Thoughts.

HIghly suspect the meter. Other possibilities do exist.

-136 amps at 24 volts is a very large load. Bigger than a windlass. So as long as there is nothing like that running, then its an instrument problem.
What does it read with all loads shut off and battery charger off?
Do you know if the meter uses a shunt or a coil?
Trace the leads from the meter. Check for loose connections.

High Wire said:

-136 amps at 24 volts is a very large load. Bigger than a windlass. So as long as there is nothing like that running, then its an instrument problem.

What does it read with all loads shut off and battery charger off?

Do you know if the meter uses a shunt or a coil?

Trace the leads from the meter. Check for loose connections.

Click to expand...

What does it read with all loads shut off and battery charger off? The same to a point. It does go up or down quite a bit. Sometimes it just reads normal.
Do you know if the meter uses a shunt or a coil? I don’t know but can easily check.
Trace the leads from the meter. Check for loose connections. Will do

first turn off your inverter

bayview said:

first turn off your inverter

Click to expand...

Yes, I have. Their are a total of 3 and all are switched off. I have also turned off the mains with the same results showing on the display. Right now we are connected to shore power but it also comes and goes with genset running and cruising.

Check your meter, it may be bad.

The Selene owner's site may point you towards the problem, especially if reading is correct. Some years ago we spent time discussing electrical issues with a few Selene owners, this one sounds vaguely familiar. Also, turning off your inverter does not bypass it. An inverter bypass switch is a nice to have when trouble shooting.

JS, it has been over 10 days now - what was the problem?

Ammeter may actually be a voltmeter reading the voltage drop on a shunt (very low ohm resistor). If a poor connection on the shunt, the volt drop can swing wide even though the amps are normal. Trace meter leads and see if they go to a shunt.

Ski is correct. Here is some detail.
http://i1.ytimg.com/vi/7MGed7WKwAA/hqdefault.jpg

The black thing is a very low value resistor

The meter is a sensitive voltmeter, that has a scale marked in Amps. Note exactly 4 wires connected to the shunt. Two large, two small. It should be in the NEG side of the battery bank
.

Ski in NC said:

Ammeter may actually be a voltmeter reading the voltage drop on a shunt (very low ohm resistor). If a poor connection on the shunt, the volt drop can swing wide even though the amps are normal. Trace meter leads and see if they go to a shunt.

Click to expand...

Ski, although you may be correct, the volt meter to the left is reading 27.7 which is normal. His inverter monitor/BMK setup (if so equipped) should be able to discern accurate amp draw, hopefully the same as meter shown. The "amp" meter may well predate the inverter install