Is your disconnect on the positive or negative?
Mounting the shunt properly should resolve this issue. Battery negative to shunt, then shunt to negative buss. All negative connections before shunt. This is the only way to capture all in/out movement of energy by the batteries.
Memory has it that the positive side of shunt needs energy(very small parasitical load) to maintain the ongoing soc calculations but I would have to go back to the documentation to verify.
The documentation for the Trimetric should cover this issue - but a phone call or email to Bogart should net the answer you seek.
