Trimetric

zozomike

Hi, I have installed the 6 new panels and the MX 60, Relocated the 12 existing panels and rewired everything. Battery seems happy. I believed that I should keep the two arrays wiring completely separate all the way to the battery, which I did. In that vein I did not connect the negatives of either charge controller to the Trimetric, only the inverter. The readings I am getting seem reasonable. The Trimetric manual howvever states I should connect all negatives to the monitor.
Did I screw up again? Attachment not found.Attachment not found.

Cariboocoot

Re: Trimetric

Um, the Trimetric's shunt has to measure all current going in to or out of the battery. It sounds like you bypassed the shunt with the output of at least one of the controllers. This should not be.

As far as keeping array separate on controllers is concerned, this applies only to paralleling both positive and negative on the input side; the output is inevitably going to be paralleled because they both connect to the same battery. The only 'isolation' on the output is a matter of wire size for the current carried (after the point where the two meet the current potential is higher than either single controller) and having separate over-current protection per controller.

zozomike

Re: Trimetric

Cariboocoot wrote: »

Um, the Trimetric's shunt has to measure all current going in to or out of the battery. It sounds like you bypassed the shunt with the output of at least one of the controllers. This should not be.

As far as keeping array separate on controllers is concerned, this applies only to paralleling both positive and negative on the input side; the output is inevitably going to be paralleled because they both connect to the same battery. The only 'isolation' on the output is a matter of wire size for the current carried (after the point where the two meet the current potential is higher than either single controller) and having separate over-current protection per controller.

Ok, thanks. As I understand the Manual all negatives connect to the shunt. As I said I only connected the negative of the inverter. So I will reconfigure cables to attach the negatives of each controller to the shunt. I guess that just means cut and terminal the #2 negatives from the controllers to the batt and bolt into the shunt the 2/0 negative from the inverter is already there. Yes I installed breaker/shut offs on both sides of both controllers. 80 and 100 amp at mx 80 and 60 and 80 amp at the mx60. Larger breakers at the battery shut off.
Thanks again

zoneblue

Re: Trimetric

Its not that all the negatives have to be attached to the shunt,just that no loads or chargers are attached to, or beyond, the battery side of the shunt. How you lay that out is up to you, usually some form of negative bus.

zozomike

Re: Trimetric

zoneblue wrote: »

Its not that all the negatives have to be attached to the shunt,just that no loads or chargers are attached to, or beyond, the battery side of the shunt. How you lay that out is up to you, usually some form of negative bus.

Hmm, A bit confused now as the two helpful replies seem to conflict. Of course no loads are connected to the negative between the battery and the shunt. Actually since I only have two CC and the inverter I had just run all three negatives to the negative of the batt and all three positives to the positive terminal of the battery, no buss. Only interrupting the negative of the inverter with the shunt. So If I understand you, I am ok, I do not need to pass the negatives of the CC through the shunt? If not how does the trimetric know power in (to the battery from CC ?)
Thank you both!

Cariboocoot

Re: Trimetric

zozomike wrote: »

Hmm, A bit confused now as the two helpful replies seem to conflict. Of course no loads are connected to the negative between the battery and the shunt. Actually since I only have two CC and the inverter I had just run all three negatives to the negative of the batt and all three positives to the positive terminal of the battery, no buss. Only interrupting the negative of the inverter with the shunt. So If I understand you, I am ok, I do not need to pass the negatives of the CC through the shunt? If not how does the trimetric know power in (to the battery from CC ?)
Thank you both!

The 'conflict' is whether you're talking about electrical placement or mechanical placement. The two are not necessarily the same.

Electrically all loads and charge sources are on one side of the battery monitor's shunt and the battery is on the other. All current in or out of the battery needs to go through the shunt.

Mechanically the wires for the charge controller(s) and inverter do not have to actually be attached to the shunt terminal; they can be attached to a bus bar which is then wired to the shunt terminal.

(And people wonder why I sometimes delete confusing response posts.)

Cariboocoot

Re: Trimetric

I'm going to try a 'word diagram' here and see if it makes it easier.

CONTROLLER #1 (-) --->|
CONTROLLER #2 (-) --->|<--->SHUNT<--->(-)BATTERY
INVERTER (-) <

---

|

The three vertical bars representing a bus bar, the dash lines wires, the arrows indicate direction of current flow.

zozomike

Re: Trimetric

Got it, that is what I thought you meant in the first answer. As always thanks, Thanks, Thanks!