Zamp port questions

[hitectoys]

I just realized that the zamp port connects directly to the battery. I realized this when I plugged my portable solar panel into the Zamp and did not get any increase in volts or amps at the controller for the roof top solar panel.. Since my portable solar does not have a controller should I get one or wire the zamp port into the existing controller? If I do not do either and leave the zamp direct connection into the battery will I damage my two six volt flooded batteries with over charging. My portable panel is rated at 120 w 6 amps 20 volts. The roof top panel is 190W.

[SRS]

Originally Posted by hitectoys

I just realized that the zamp port connects directly to the battery. I realized this when I plugged my portable solar panel into the Zamp and did not get any increase in volts or amps at the controller for the roof top solar panel.. Since my portable solar does not have a controller should I get one or wire the zamp port into the existing controller? If I do not do either and leave the zamp direct connection into the battery will I damage my two six volt flooded batteries with over charging. My portable panel is rated at 120 w 6 amps 20 volts. The roof top panel is 190W.

Without a controller I believe you can damage your batteries through over charging. You can get a fairly inexpensive PWM controller like this one:
https://smile.amazon.com/gp/product/...e?ie=UTF8&th=1
I just attached the controller to the back of my panel with VHB tape after wiring it up. Since your mixing different size panels, you get more efficiency keeping them on separate controllers particularly if, for example, your roof solar is in the shade. At least that's been my experience. Other folks may have different opinions. below is an article on Using Mismatched Solar Panel Sizes that may help to explain some of the issues.
https://www.explorist.life/using-mis...r-panel-sizes/

[Tosh]

Escape states that their external solar port is wired into the charge controller (at least for the current production models).


"Exterior Solar Port wired to Regulator"


I was about to order a Zamp panel without the integrated controller. Now I need more information.....


How can I know for certain if my external port is wired into the battery, or into the charge controller?

[brroberts]

Originally Posted by Tosh

Escape states that their external solar port is wired into the charge controller (at least for the current production models).


"Exterior Solar Port wired to Regulator"

How can I know for certain if my external port is wired into the battery, or into the charge controller?

It seems ETI has done it both ways. Mine came wired to the controller. Measure current, do a continuity check on the wiring, or follow the wires to verify how yours is built.

[SRS]

Originally Posted by Tosh

Escape states that their external solar port is wired into the charge controller (at least for the current production models).


"Exterior Solar Port wired to Regulator"


I was about to order a Zamp panel without the integrated controller. Now I need more information.....


How can I know for certain if my external port is wired into the battery, or into the charge controller?

My 2022 E17 was not wired to the controller and there was a period of production during 2022 that could it could be wired either way. It's my understanding that they are back to wiring the Zamp port into the controller but it never hurts to check. Escape sent out a notice and produced a video regarding this Issue:

https://www.youtube.com/watch?v=xGcq2tkHHOc

Attached is a photo of how my controller was wired and to diagnose your wiring, you'll probably need to trace the wires from your Zamp port and your batteries to the wago connectors. The video explains it very well but basically, if the thicker solar wires goes into the PV connection on the controller, your Zamp is wired to the batteries. If they go into the wago connectors, then the zamp is wired to the controller.

[SRS]

Originally Posted by Tosh

Escape states that their external solar port is wired into the charge controller (at least for the current production models).


"Exterior Solar Port wired to Regulator"


I was about to order a Zamp panel without the integrated controller. Now I need more information.....


How can I know for certain if my external port is wired into the battery, or into the charge controller?

I should mention that you should check the polarity of your Zamp port, i.e. is the male side positive or negative and match the solar panel connector to match.

[Sean Murry]

In our trailer the zamp port is wired to the controller. As SRS has mentioned check the polarity. Zamp tends to be the reverse of most solar panels. We had to attach a polarity reverser to the wires coming from the solar panels to the Zamp port.

[Carmel Clown]

On my final build sheet it states that a solar panel that is plugged into the Zamp port must have a controller.

[Perry Butler]

Originally Posted by Sean Murry

In our trailer the zamp port is wired to the controller. As SRS has mentioned check the polarity. Zamp tends to be the reverse of most solar panels. We had to attach a polarity reverser to the wires coming from the solar panels to the Zamp port.

A polarity reverser is just a temporary fix. Eventually they fall off and you fry your panel(s). A permanent fix is to wrap the black wire from the Zamp port with red electricians tape and your red wire with black electricians tape. Once done the red wire goes in the positive buss of the controller and the black wire into the negative buss, like it should have been in the first place. Who wants to remember incorrect color code. It’s just bad electrical practice. Put the correct color on the wires and you never have to make sure the reverser is in place because it’s now visually wired correctly.

I wrapped the wires in our 5.0 and now the new owners won’t have to question the wire color, and just did this two weeks ago with the Zamp port to our new camper. Easy Peazy! And you never have to check to see if the reverser is still in place.

Enjoy,

Perry

[alanmalk]

Originally Posted by hitectoys

...
My portable panel is rated at 120 w 6 amps 20 volts. The roof top panel is 190W.

Your panel may be rated for those numbers, however, you will only get them if you camp at the equator, in the summer, and religiously aim your panel at the sun all day. In the real world you are lucky to get half that, and realistically, your panel output will be closer to the typical trickle charger. Yes, it is possible to damage your big batteries, but you would have to work at it.

Try this: On a bright sunny day deploy your portable in the morning with an unobstructed view of the sky. Around 1 pm use a good voltmeter and measure the voltage - right at the actual battery terminals. Is it over 13.8 volts? In that case it might be in your best interest to get a small controller.

[Tosh]

@ SRS - thanks very much - I should be able to do this

[John in Santa Cruz]

My MPPT rooftop solar system seems to be able to make 6 * rated watts watt*hours per day, so for a 360W panel (36-40V, 8-10 amps), over 2000 WH/day, as long as its parked out in the open on a clear day, and its not the dead of winter.

[Perry Butler]

Originally Posted by alanmalk

Your panel may be rated for those numbers, however, you will only get them if you camp at the equator, in the summer, and religiously aim your panel at the sun all day. In the real world you are lucky to get half that, and realistically, your panel output will be closer to the typical trickle charger. Yes, it is possible to damage your big batteries, but you would have to work at it.

Try this: On a bright sunny day deploy your portable in the morning with an unobstructed view of the sky. Around 1 pm use a good voltmeter and measure the voltage - right at the actual battery terminals. Is it over 13.8 volts? In that case it might be in your best interest to get a small controller.

Ah……..this discussion is for a portable panel. We just left Death Valley where the low for our 100 watt Renogy panel was around 96 watts and the high was 106 watts or 96-106% of rated wattage. Portable panels are tilted to the sun so the time of year or distance from the equator makes little difference.

The portable controller and panel are put away, so no Victron screenshot for the portable. We’ll be at Gilbert Ray tomorrow and the controller/panel will be hooked up there, so I could take a screenshot

OTOH, our 160 watt panel on the roof didn’t get much over 102 watts, because it’s flat on the roof.



Enjoy,

Perry

[John in Santa Cruz]

what counts is the total watt*hours a day your solar panel generates. My ballpark number is, 6 * rated watts in watt*hours for central california latitudes with a flat mounted monocrystalline panel on an MPPT controlller parked where there's no external shade, and of course, no clouds.

btw, time of year DOES matter, when the sun is lower in the sky, its not as bright, there's not as much W/m^2 or whatever units they use, even if your panel is pointed straight at the sun.

[Perry Butler]

Originally Posted by John in Santa Cruz

btw, time of year DOES matter, when the sun is lower in the sky, its not as bright, there's not as much W/m^2 or whatever units they use, even if your panel is pointed straight at the sun.

We were quite satisfied with our 100 watt Renogy portable putting out 106 watts a little over a month after the shortest day of the year.

I’ve never bothered to try our 100 watt Renogy in our seasonal campground on June 21 in full noon day sun. However, I doubt I’ll get much more than the 106 watts the Victron 100/20 solar charge controller recorded a couple of days ago.

We’re currently boondocking south of Wikieup, AZ after traveling from Death Valley. Obviously the portable is put away. The 160 watt rooftop panel maxed out at 102 watts and 380 watt hours, not enough to replace the 28 ah’s we used last night. At Gilbert Ray I’ll be hooking up the portable with the rooftop and see if it fills the batteries in two days or less. We have an inside campsite and may not have the full exposure for the portable like we had at Death Valley.

Enjoy,

Perry

[Radar1]

On our 2020 19', the Zamp connector wiring (thinner wires barely visible in top left corner of photo) is joined with the thicker rooftop solar wiring (visible in top right of photo) near the controller, and then run into the controller. The final wiring run is short, so they don't need to use the thicker wiring to reduce voltage drop.
When I designed the solar for our older Scamp, I just happened to wire my portable panel the same way Zamp does, since that made more sense to me, so I can just plug my portable panel into the Zamp connector without an adapter.

[BobG]

Originally Posted by hitectoys

... Since my portable solar does not have a controller should I get one or wire the zamp port into the existing controller? If I do not do either and leave the zamp direct connection into the battery will I damage my two six volt flooded batteries with over charging. My portable panel is rated at 120 w 6 amps 20 volts. The roof top panel is 190W.

If you connect different voltage panels in parallel to your solar charge controller (SCC) the amp output will be the sum of the panels but the voltage will be at the lowest panel connected. Look at the panel specifications for the Voltage MPP for the panels. It is possible to connect a low output portable panel in parallel with larger output fixed panels that have a higher voltage and end up with less output than if you do not connect the portable panel to the SCC.

If you have a significantly mismatched voltage of panels then use a separate SCC for the portable panel rather than connect in parallel to the same SCC.

Don't connect panels directly to the battery unless they have a built in SCC and it is designed for your batteries. Zamp panels may have a built in SCC. I don't know anything about Zamp panels but if they do have an integral SCC then you might want to check if its output is for your type of batteries and that it matches the voltage output of the SCC and WFCO charger in your trailer.

If you use a factory supplied port for portable panels you should sort out the polarity of the contacts and where they connect; battery or SCC or are just dead ended inside the electric locker. I would not trust the color of the conductors until you check them.

This is one place to learn a little about connecting solar panels: https://www.explorist.life/using-mis...r-panel-sizes/

Another place is Will Prowse on YouTube.

[SteveSgt]

Originally Posted by BobG

If you connect different voltage panels in parallel to your solar charge controller (SCC) the amp output will be the sum of the panels but the voltage will be at the lowest panel connected.

I won't disagree completely, but since we're driving maximum power point tracking "MPPT" controllers, they will always regulate for the maximum extractable power from the whole system.

Without presenting the math here, what you'll get is a weighted average of the VI (volts versus amps) curve of the combined panels. When your battery is demanding the most charging current (and perhaps other loads are simultaneously demanding current from your batteries), all of the panels will be delivering close to their short-circuit current "I(sc)", and close to their maximum power point (or watts) on that curve. As the current demands of the battery are reduced (the battery is near full-charge or the other loads are turned off) the panels with higher open circuit voltage "V(oc)" will do most of the work.

If your panels with higher V(oc) are in the shade, and your panels with lower V(oc) are in the sun, you'll likely still get near maximum efficiency from the best illuminated panels.

Originally Posted by BobG

Look at the panel specifications for the Voltage MPP for the panels. It is possible to connect a low output portable panel in parallel with larger output fixed panels that have a higher voltage and end up with less output than if you do not connect the portable panel to the SCC.

I have seen that happen depending on controllers, illumination, and wiring.

OTOH, on mountain-top radio installations I have connected equally illuminated panels with differences of +/- 3V of V(oc) in parallel into a single MPPT controller, and then measured +/- a few percent of the expected total power at the input to discharged batteries.

All of that said, I concur with all of the advice below--100%.

Originally Posted by BobG

If you have a significantly mismatched voltage of panels then use a separate SCC for the portable panel rather than connect in parallel to the same SCC.

Don't connect panels directly to the battery unless they have a built in SCC and it is designed for your batteries. Zamp panels may have a built in SCC. I don't know anything about Zamp panels but if they do have an integral SCC then you might want to check if its output is for your type of batteries and that it matches the voltage output of the SCC and WFCO charger in your trailer.

If you use a factory supplied port for portable panels you should sort out the polarity of the contacts and where they connect; battery or SCC or are just dead ended inside the electric locker. I would not trust the color of the conductors until you check them.

[Perry Butler]

There’s no magic about mismatched panels. It’s been the same math for decades and whether you use PWM or MPPT the math doesn’t change. Read Explorist Life’s article on the math involved with mismatched panels.

Enjoy,

Perry