75/15 to 100/20 mppt upgrade?

[gasnet]

2 170 watt panels in series 110ah 12volt bank. With my victron 75/15 mppt on sunny day i show average of 44 volts 6 amps on pv array and 15 amps (max for my controller)battery charging current.. Would upgrading to 100/20 yield anything better? If i can get max 20 amps it would it be worth it. For test purpose i drain battery to 11.80 then activate pv breaker at noon.My panels are rated at 9 amps. Mppt controller is impressive getting max charge current. Also do i really need a fuse on pv array.

[Mike90250]

Your PV could do 22A @ 15v, but it's doubtful that will ever happen, except for your test case. Shortly after dawn, batteries will normally start charging up and by noon, amps should have started to taper off.
The larger controller will help on partly cloudy days, to take advantage with the sky clears. It won't hurt anything but your wallet.

[Freeesun]

you should fuse all positive cables.

[sdold]

Also do i really need a fuse on pv array.

One panel, or several in series, don't need to be fused because they aren't capable of causing over-current. Three or more in parallel do though because a short in one panel can cause the other two to put more current through its wiring than it was designed for.

[gasnet]

Thanks everyone for your input. I didn't think i needed a fuse on my pv array also. I don't have RV. This is on my roof. I live near the water on south shore of long island. Lots of trees. Lose power all the time. Have a generator but not needed for just a few hours. I use my 200ah agm battery and a 600w Xantrex Prosine inverter. I charge the Battery just once a month for 24hrs. Its strictly for backup power. I hope once a month is ok. Any thoughts on this? I can run TV, satellite reciever, 2 Led Lamps, phone and my router.Also Cpap machine. All that is about 490 watts. Its Goes for 6 hrs before my inverter beeps. So i go 5 hrs and shut off everything and can sleep all night with cpap machine. My 340 watt solar array is hooked up to my 110ah battery as i noted in first post. I use this for my landscape lighting for front and back of House. I use about 2 amps dc in winter and 4 amps dc in summer. Never a problem charging. Sunny day its on Float by Noon. Cloudy day takes longer but it still makes float by 3 or 4pm.

[gasnet]

On a sunny day i used my solar system with a cheap 700 watt inverter. I plugged my marine charger into it so i can charge the 200ah battery. I then turned on my 600 watt Xantrex inverter with everything running. About 490 watts. I can go all day. My charge controller max out at 15 amps current. Yes i could switch the charge controller to the 200ah battery, but thats to much of a hassle for a power outage a handful of times a year. Seems silly but it worked great.

[Mike90250]

you should fuse all positive cables.

That only applies if you have the negative side grounded. if not grounded, you need to fuse + & - leads.

There are many configurations and if you are unsure, post a clear schematic or consult a competent electrician.

[Freeesun]

I fused all positive in my setup and fused the negative on the batter but no other negatives. My system is 12v so I didn’t ground it.

[gasnet]

.bhi