Zamp Port problem June 15 to Oct 6

[SRS]

Originally Posted by Eggscape

I think the key words are “in full sun and perfect alignment”. There are lots of variables in a flat roof top solar panel and personally with the testing in my Canadian location of a 180 panel on the ground flat, (and clean) I could never get anywhere near 90%. The difference between horizontal and pointed directly at the sun is outstanding. I would say that a 100 watt panel pointed at the sun will sometimes come close to the output of a roof top unit unless the sun is directly overhead.

Absolutely True. That is why a solar suitcase or other external solar connected to the Zamp port should have it's own controller. With panels in parallel, using the same controller, the larger panels output will reduce the output of the smaller due to shade or it's angle to the sun. The two parallel panels will produce a greater output, it just may not be sufficient for your needs in some situations.

[bborzell]

Originally Posted by Eggscape

I think the key words are “in full sun and perfect alignment”. There are lots of variables in a flat roof top solar panel and personally with the testing in my Canadian location of a 180 panel on the ground flat, (and clean) I could never get anywhere near 90%. The difference between horizontal and pointed directly at the sun is outstanding. I would say that a 100 watt panel pointed at the sun will sometimes come close to the output of a roof top unit unless the sun is directly overhead.

This time of year, when the sun is pretty much never directly overhead, it is common for my 100W suitcase to beat both 190W panels on the roof. The flat rooftop panels simply cannot catch what they cannot see.

[Perry Butler]

Originally Posted by SRS

That is why a solar suitcase or other external solar connected to the Zamp port should have it's own controller.

The two parallel panels will produce a greater output, it just may not be sufficient for your needs in some situations.

True.

Originally Posted by SRS

With panels in parallel, using the same controller, the larger panels output will reduce the output of the smaller due to shade or it's angle to the sun.

Not true.

As you stated we're talking parallel. The panel that is reduced is the one with the higher VMP. It has nothing to do with the size of the panels. Either the one on the roof or the portable may be reduced, it depends on which panel has the higher VMP.

I suggest you read Explorist Life's "Using Mismatched Solar Panel Sizes."

We added three Renogy Compact 100 watt panels (18.6 VMP) to our single GoPower 170 watt panel (VMP 19.3) all on the roof in parallel feeding our Victron 100/30 controller. Using the math for a parallel connection, the combination gives us 463.7 watts, for a loss of only 6.3 watts.

I was going to use Renogy Eclipse 100 watt panels (VMP 17.7), but they would have only given us 458.3 watts. I sent the Eclipse panels back and used Renogy's 100 watt Compact panels to give us 15.4 more watts. An added benefit was the three Eclipse panels were over $80 more for each, a savings of $240.

Before the addition of the three 100 watt panels we were using a 100 watt Renogy portable hooked to a separate Victron 100/20 controller. In the 1 1/2 years since the install of the extra 300 watts we have yet to need the portable, but we still carry it just in case.

Food for thought,

Perry

[SRS]

Originally Posted by Perry Butler

True.

Not true.

As you stated we're talking parallel. The panel that is reduced is the one with the higher VMP. It has nothing to do with the size of the panels. Either the one on the roof or the portable may be reduced, it depends on which panel has the higher VMP.

I suggest you read Explorist Life's "Using Mismatched Solar Panel Sizes."

We added three Renogy Compact 100 watt panels (18.6 VMP) to our single GoPower 170 watt panel (VMP 19.3) all on the roof in parallel feeding our Victron 100/30 controller. Using the math for a parallel connection, the combination gives us 463.7 watts, for a loss of only 6.3 watts.

I was going to use Renogy Eclipse 100 watt panels (VMP 17.7), but they would have only given us 458.3 watts. I sent the Eclipse panels back and used Renogy's 100 watt Compact panels to give us 15.4 more watts. An added benefit was the three Eclipse panels were over $80 more for each, a savings of $240.

Before the addition of the three 100 watt panels we were using a 100 watt Renogy portable hooked to a separate Victron 100/20 controller. In the 1 1/2 years since the install of the extra 300 watts we have yet to need the portable, but we still carry it just in case.

Food for thought,

Perry

You are correct on the second point for sure. And yes I've read that article several times. My electrical engineering skills are minimal at best so what little I know comes from the little tests I've done.

[nrthwds]

I have a 2020 21C with 2 solar panels and a zamp port.. I don't have any portable panels yet and am curious how to know if my Zamp port is wired correctly? I know nothing about electrical systems.

[Shibumi]

My Zamp port was installed on my 2019 but not connected to anything! I have yet to use it.

[SRS]

Originally Posted by nrthwds

I have a 2020 21C with 2 solar panels and a zamp port.. I don't have any portable panels yet and am curious how to know if my Zamp port is wired correctly? I know nothing about electrical systems.

Not sure if you are referring to polarity, i.e. positive and ground connection orientation or the recent issue regarding "if" it is wired to the solar controller or to the batteries in 2022 models built between June 15 to October 6?

Your model year standard was zamp port wired to solar controller. You would have to trace the zamp wiring to see where they go. To test polarity, us a multi-meter and check the exterior connections on the outside of your trailer.


Post #7 of this thread has a link to the rewiring video. My post #11 shows my wiring as delivered with the zamp port wired directly to the batteries.