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mangojam42 02-05-2017 22:32

wiring panels of different ratings
Hi Cruisers!

A friend recently gifted me a pair of 12V 50w solar panels after I complained that my 12V 140W solar panel just wasn't giving me enough power to cover my needs. With his addition I would expect to up the wattage to 12V 240W and hopefully get closer to 20 amps instead of 10 amps going to the battery.

In real world conditions I get about 6-8 amps from the 140W panel so maybe the extra panels could push that up to 12 to 15 amps?

The panels are all flexible (Monocrystalline silicone)but have different ratings. I currently have an mppt charge controller, but it is rated for 10A, So I know I'll have to change this.

My question is: can I just buy an mppt charge controller which is rated at 20A or even 30A (in case I want to add a fourth panel), AND Is it a simply just a matter of wiring all panels in parallel to a branch connector?
(i.e. 3 in 1 out on both the + and -)?

This is the spec from the 140Watt panel:
Rated Power (+/- 5%) - Pmax 140 W
Open Circuit Voltage - Voc 29.5 V
short circuit current - Isc 5.8 A
Maximum Power Voltage (Vpm) 24.9 V
Maximum Power Current (Imp) 5.5 A

These are the specs from the 2 50W panels
Rated Power Output: 50W
Open Circuit Voltage [Voc]: 21.2V
Short Circuit Current [Isc]: 3.05A
Optimum Operating Voltage [Vmp]: 17.6V
Optimum Operating Current [Imp]: 2.84A

This is the 30A Mppt charge controller I would like to get:from Amazon

Any solar gurus who can give me some advice?


StuM 03-05-2017 05:46

Re: wiring panels of different ratings
This has been answered in the other thread you started with the same question:

Best if any further responses are made there?

smac999 03-05-2017 09:04

Re: wiring panels of different ratings
No buy a 2nd mppt for the different size panels

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