Flexible Panels, Mounting Methods and Heat

[T1 Terry]

The heat transfer and dissipating the heat is always the problem with diodes of any type. Schottky diodes have the fastest switching time with the lowest forward voltage drop and therefore the lowest heat generation ... the diode killer.
The next thing is to look for a diode that is rated at double the expected current, a half loaded diode has 1/4 of the forward voltage drop compared to a fully loaded diode, less voltage drop = less heat generated.
we have just received some diodes we think will be ideal for the job, but haven't had a chance to test them. Sure hope they work the way the specs say they will as we had to order a min of 500 units.

T1 Terry

[Mrcoolabah1au]

Send them back 🛩🛩🛩

[Barboots]

Send them back [emoji927][emoji927][emoji927]

I don't know if you missed it... I received replacement panels when the visual defects first appeared.

[Barboots]

I'm half way through routering the recesses for the aluminium plates. I still have to mark out, drill and tap the plates I've cut up too...
[emoji19]
At least the sun intensity has eased off.

[Barboots]

One side done...

[Barboots]

While the rain stopped play, I hacked the blocking diode from one of the failed panels. The datasheet for the 15SQ045 device suggests that this aspect wasn't the source of the problem. http://cloud.tapatalk.com/s/5a387606c7f94/15sq045.pdf

[dapope]

Its all a bit of a puzzle really... I have 6 x 80w panels that are 20 yrs old.I want to replace them with newer and more efficient panels, but am still tossing up on what style...

[Barboots]

Its all a bit of a puzzle really... I have 6 x 80w panels that are 20 yrs old.I want to replace them with newer and more efficient panels, but am still tossing up on what style...

I'd fit glass if I were more comfortable with the additional weight up high... however with a tall caravan it's simply not a good way to go as far as stability. So I'm kind of stuck with flexibles as a solution. Hopefully with the expansion/contraction differences sorted out the ETFE panels will last longer. I'm certainly not going to be doing this every year and a half ongoing!

That said, as I'm completing this rework I'm thinking that I should chuck the Thermoclear and have some aluminium sheet punched and stamped to use as the support mechanism instead. Like the old recovery tracks the hardcore guys used to to have on the sides of their Landys.

Cheers, Steve

[T1 Terry]

While the rain stopped play, I hacked the blocking diode from one of the failed panels. The datasheet for the 15SQ045 device suggests that this aspect wasn't the source of the problem. http://cloud.tapatalk.com/s/5a387606c7f94/15sq045.pdf

Did you determine if it was installed as a blocking diode or a by pass diode? These diodes are listed as bypass diodes and very few solar panels have blocking diodes these days because it reduces the output in an STC test on the lightbox.

T1 Terry

[Barboots]

Did you determine if it was installed as a blocking diode or a by pass diode?
T1 Terry

Terry it was across the output of the panel between the positive and negative. Ah... I see your point. It is for bypassing the panel when series connected, and not actually helpful for the situation under discussion. My mistake.

Boo. I should have ordered those special diodes I found. [emoji34]