Good day,
I have a caravan with a mppt 100/20 solar controller & IP 65 smart charger & a connection to the alternator of the towing vehicle. I have four questions:
1. What manages the decision to charge from the MPPT or IP 65?
2. What manages the decision to charge from the MPPT or alternator?
3. If the system is charging from the IP 65 will the load side of the MPPT remain active?
4. What is the maximum allowable current drawn on the demand side of the MPPT?
Thanks in advance.
Hi Dewald. Essentially Voltage, The charger that reaches it's V target 'earliest' will back off first once it's satisfied it's own goal. Then the second will follow, and the third with the highest settings will continue - and even then will back off when the batts are approaching full charge.
So there's no central decision maker. Each unit operates independently to it's own V target. If all 3 are connected then they'll all remain 'active', but not necessarily producing Amps. If you must prioritize them deliberately, maybe look to the V option settings.
Max batt A could be exceeded starting with low batts, but with Pb's in practice will be usually self-limiting. Just something to confuse you more, hey.
The max allowable pv dc current for your 100/20 is listed at 20A Vsc. That's really a stringing design limit though, and in practice the pv A will be much lower, depending on how you wire your panels.
