solar upgrade questions

[kvv515kvv]

Hi.
i just got pasport 221bh
it has 200w solar panel and charge controller victon mppt 75/15
i am going to ad 3 more panels and upgrade victron to mppt 150/70
(2 panels in series) parallel (2 panels in series)

1. can i use existing wiring from roof to mppt?
2. can i use existing victon mppt 75/15?

[mikec557]

Originally Posted by kvv515kvv

Hi.
i just got pasport 221bh
it has 200w solar panel and charge controller victon mppt 75/15
i am going to ad 3 more panels and upgrade victron to mppt 150/70
(2 panels in series) parallel (2 panels in series)

1. can i use existing wiring from roof to mppt?
2. can i use existing victon mppt 75/15?

The answer to question 1, I think your safest bet is to go up on the roof and look at the rooftop gland. Mine has a two port Zamp/sp (SAE) connection. Embossed on it, it says 500 Watts max. Some Keystone models have a three port connector. I don't know what the max watt is for that.

RE question 2, I haven't done the calculations for series/parallel, but I don't think you can stay under the 15 amp limit of the 75/15. Doesn't each of your 4x 200 watt panels put out about 10 amps?