Salvo wrote:
The OP shouldn't be seeing a voltage spike in the magnitude of 0.7V. There could be a bad connection, or batteries are old....Sal
I don't see a spike of 0.7V, I would say it is more in the ballpark of 0.2-0.4V. But this is based on what I've seen on the MSVIEW software status which, while real time, may still not be reflecting the true extent of the spike. Like I just recently mentioned in a reply, I do have a way to view the voltage right at the inverter input terminals but I have not monitored the voltage there during a spike. I will look into that. The spike occurs for less than a second. My inverter claims a high voltage disconnect at 15V, but I witness it faulting at a voltage slightly lower than that. I'd say at around 14.8-14.9V.
What are the conditions when inverter turns off? - My issue is only a concern when I'm well into a solar charging day and the system is humming along at the bulk/absorption setpoint. During steady state operation, no problem and no faulting. But if I remove a load from the inverter while the battery charging voltage is clamped at the bulk/absorption setpoint, I see a quicks spike in battery voltage and it is high enough to trip my inverter's high voltage disconnect.
1. Battery type and age - all trailer and battery components are brand new as of the end of 2011 when I bought the trailer new from the dealership. The 2 batteries are the stock dual purpose marine batteries. Exide Nautilus 12V, 70 Ah each, wired in parallel with 0 gauge wiring. Solar was installed during winter of 2011/2012, all components brand new. The inverter wiring was also installed during winter 2011/2012, but the current inverter is actually new from this 2012/2013 winter.
2. Cabling inverter and charge controller - cables are about a 5' wire length distance from the batteries. 4 gauge wires in the solar setup, 0 gauge wires in the inverter setup. All wiring terminates right at the battery terminals using ring connectors. The charge controller is a Morningstar Tristar PWM 45. I am using the voltage sense wires and remote temperature sensor. Voltage sense wires are installed on the same terminals as the rest (+ of one battery and - of the other)
3. Battery voltage just prior to shut-down - currently happens while 14.40 V (my bulk/absorption setpoint, temperature compensation has been turned off for cooler-than-baseline temps as described in the first few pages of this thread).
4. Battery voltage right after shut-down - currently 14.40V (my bulk/absorption setpoint)
It may be time to measure battery resistance. Do you have an amp meter? - no
Another detail I have not yet mentioned, I had to add almost a gallon of distilled water between the 2 batteries this spring to top them off. The top of the plates was just above the water level prior topping off. The batteries have always been left in place on the TT and until recently at the Morningstar's stock 14.60V charging algorithm with full temperature compensation and automatic equalization every 28 days (15.3V for 3 hours). We had a typical Montana winter, although not as many arctic cold periods as usual.
