On Thu, 21 Oct 2004 08:10:36 -0700, "Steve" wrote:

Correct me if I'm wrong (not being an electrical type But aren't
external shunt type amp meters milli-volt meters and the meter simply
measures the voltage drop across the shunt??

That is correct.

I don't see that the voltage could be reversed to operate the meter on
either side of zero.

The polarity of the voltage across the shunt depends on the direction
of current flow. The shunt is usually installed so that a charging
current is a positive voltage, discharge negative.

I always assumed that this was the reason you we never see any external
shunt type 'zero center' amp meters.

I'm sure they can be purchased somewhere but why bother when the price
and availability of digital meters has improved so much.

If anyone knows of a 150-0-150 amp, shunt type amp meter, I would like to
know where I can get one. I could then monitor my house bank charge and
useage at the DC panel without opening the inverter/charger locker.

Shunts are readily available from a variety of sources. Finding a
suitable analog meter to go with the shunt may take more time but they
are out there (perhaps from Grainger?).

One of the issues with a high current analog meter such as 150-0-150
is that small current values are difficult to read accurately whereas
with a digital meter it doesn't really matter.