PT, the guy has only one 120w panel--whyinhell would you tell him to get MPPT!!!!
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The Trimetric only reads what goes across the shunt, so be sure the neg output of the solar controller is on the outboard end of the shunt, not the battery neg post end of the shunt.
Check to see you have the small wires on the shunt at the right ends iaw the Trimetric manual's diagrams.
When using the Trimetric to monitor solar, be sure to turn off the automatic AH reset, or it will keep going back to zero when amps go negative, especially as it gets dark. Instructions for programming that in the manual.
With everything in the rig across the Trimetric including solar, you have to derive what is the solar part. this is fairly easy once you know your usual day. eg, if solar is doing +10amps and you have a light on at -3a, then the Trimetric will show the net of +7 amps.
