Solar Panel

work2much wrote:

CA Traveler wrote:

devildog1971 wrote:
(for 4K I could have put 400 watts or more on the Bigfoot)

No doubt.

As a DIY I paid $1450 for 750W in 2014 for all of the parts including UV wires, aluminum for mounting and SS screws and bolts, etc. This included a high end Morningstar MPPT 60 controller. All panels in series which provides much better shade performance than parallel panels, but that is a whole different topic.

For shaded conditions parallel is superior. In series shading one one panel affects all the panels. In parallel it only affects the shaded panel.

I should have added that serial is superior when the panels have bypass diodes. Virtually all larger panels have bypass diodes. This may not apply to some 12V panels.

My 3 serial panels (90V total) have 3 bypass diodes each. Each diode will bypass 20 cells (10 volts) of my 60 cell panels when there is a shadow on that portion of the panel. So basically I have 9 serial panel sections. When 1 section has a shadow for example the diode causes a short which is 0 volts and passes the full amps of the other 8 sections. So the result is (90V-10V) * 8A (panel Imp) or 8/9 of the panels power.

The same panels in parallel result in 1/3 power loss, hence the voltage is lower than the other 2 panels. The result is the power is 6/9 of the 3 panels vs the serial 8/9 of the 3 panels.

In the past I've posted graphs showing the effect of bypass diodes. It's easy to see the 10V steps with full amps for the given sun condition on leafy shade, hard shade and other types of shade.

From past comments I'm aware that panel bypass diodes with serial panels and shade and not well understood. But with some electrical knowledge and research what I've posted can be verified.

Dog, not to change the subject but how did you make out with the batteries and are you up in Acadia now?

CA Traveler wrote:

devildog1971 wrote:
(for 4K I could have put 400 watts or more on the Bigfoot)

No doubt.

As a DIY I paid $1450 for 750W in 2014 for all of the parts including UV wires, aluminum for mounting and SS screws and bolts, etc. This included a high end Morningstar MPPT 60 controller. All panels in series which provides much better shade performance than parallel panels, but that is a whole different topic.

For shaded conditions parallel is superior. In series shading one one panel affects all the panels. In parallel it only affects the shaded panel.

The advantage to series connection is that you will have a higher voltage with less amperage. Less amperage means you can run smaller wires with the same voltage drop as parallel with larger cables.

Here is an interesting video showing the difference. Per also has some pretty interesting videos of his Tesla powered RV.
https://www.youtube.com/watch?v=kHafdxzIMh4

devildog1971 wrote:
(for 4K I could have put 400 watts or more on the Bigfoot)

No doubt.

As a DIY I paid $1450 for 750W in 2014 for all of the parts including UV wires, aluminum for mounting and SS screws and bolts, etc. This included a high end Morningstar MPPT 60 controller. All panels in series which provides much better shade performance than parallel panels, but that is a whole different topic.

D.E.Bishop wrote:

CA Traveler wrote:
Could also be the controller or even wiring.

To check the panel: Look up the specs. Then locate the panel wires (not the controller output wires), disconnect one and then with good sun check the voltage which should be very close to Voc (open circuit). Next short the 2 wires and the amps should be close to Isc (short circuit). These 2 measurements are a very good test of a panels performance.

Ok, I don't wish to appear dumb but if he were to short the two wires from the panel, where would he place the meter leads. When shorted it would appear to be a close loop.

I use a AC/DC clamp on ammeter to measure amps, just clamps around the shorted wires. It also measures voltage, ohms, etc. Or use an ammeter on the wires and many meters have 10A capability.

got it fixed the fuse, was behind board thanks guys I have had two previous truck campers then a class C then the wife had to have a 40 foot diesel A. Then she finds out our favorite places in the mountains have a 35 foot limit, of coarse it is my fault, she picked the 10-2 EX CD SE dry bath Northern Lite over the 2500 10.4 Bigfoot I do not know all the why's, the Bigfoot has a much nicer layout and hands down a better dry bath and it was 4K cheaper the only extra the Northern Lite had that the Bigfoot did not come stock with was one solar panel. And I told her the Bigfoot is already wired for solar. (for 4K I could have put 400 watts or more on the Bigfoot) Then she told me but the Northern Lite has a slide out pantry. Ahh, but the wife is happy , I am very sincere in saying thank you to all of you that helped me with my truck camper questions and solving some problems. Hope I can some day return the kindness and generosity of your time that you took to answer and help me thank you, thank you

When you say the "solar panel is not working", is this observation based on the LED and LCD indicators on the front of the Enerwatt EWC-30 solar controller? Or, did you make some voltage/current checks?

Using a volt meter at the solar charge controller what voltage if any do you see on the solar terminals and on the battery terminals?

devildog1971 wrote:
I have a new northern Lite and the solar panel is not working is there a fuse? and if iso does anyone know where to look for it it is nor in the inverter converter box with the other fuses and circuit breakers. Thanks

Our '19 NL has the solar controller output, jacks, converter output, and the fridge (supply current for the DC boiler heater only--not the fridge DC control circuits) wired directly to the battery via 4 different leads (ours are labeled). There are resettable fuses for most (if not all) of these 4 circuits/leads located directly above the batteries. Just trace the leads back to confirm. None of these circuits/leads pass through the DC/AC fuse/power panel inside the camper. Hope this helps.

CA Traveler wrote:
Could also be the controller or even wiring.

To check the panel: Look up the specs. Then locate the panel wires (not the controller output wires), disconnect one and then with good sun check the voltage which should be very close to Voc (open circuit). Next short the 2 wires and the amps should be close to Isc (short circuit). These 2 measurements are a very good test of a panels performance.

Ok, I don't wish to appear dumb but if he were to short the two wires from the panel, where would he place the meter leads. When shorted it would appear to be a close loop.