Cheap solar disconnect?

[abqlloyd]

Any ideas or thoughts on a cheap solar disconnect for a few hundred watts of panels on a cargo conversion? I'm leaning toward a Blue Sea battery disconnect rates at 60 amps and 240volts for $25.

[bdosborn]

Anderson Power Poles

Bruce

[MtnDon]

The Blue Sea, and other similar no-name switches do the job.

While on the topic of disconnects I'd like to raise the question of connections between the charge controller and the battery(s). Is there a plan for a fuse or breaker? Off grid cabin/home experience has shown that when/if a charge controller fails it most frequently fails in a short circuit mode. When/if that happens there is a massive rush of current from battery back to the CC. That can result in melted insulation and some very hot wires. Maybe even some smoke... A breaker, rated for DC, in the + line between CC and battery is an excellent precaution. Midnite Solar sells a series of DC rated breakers that could be used. They are DIN rail mount and that will likely require some home made solution unless one has space for a metal enclosure that they also sell. That vendor also sells DIN rail by the foot.


Anderson power poles can be used but there may be some arcing when they are pulled apart and the sun is shining brightly, depending on the number of amps flowing.

[lrrowe]

MtnDon,
Why would not one of these breakers work?.

http://www.ebay.com/itm/90-amp-waterpro ... 4ae1c16627

[MtnDon]

It would work as long as the maximum Voc voltage of the panel set was below 42 volts with the 25% safety factor. That would mean a maximum panel Voc of about 31 volts.

[abqlloyd]

I have inline fuses from panels to charge control - they are MC4 inline fuse holders. They can also be incorporated into the system between battery and CC.

An inline fuse from battery to inverter. I think the current fuse is 150amp.

I have some QO breakers and the small box that I could incorporate. I also ordered the "baby box" and DC breaker from Midnite for a small install that never materialized.

I liked the simplicity of the battery disconnect and more important it's small. The price doesn't hurt, either.

[abqlloyd]

I ran across these on a solar forum and they are another cheap option.

ImageUploadedByTapatalk1418617183.383027.jpg (121.41 KiB) Viewed 1983 times

$7 at Walmart. Fuses are fast-acting.

[Dale M.]

Get breaker rated at voltage and current solar panel or electronics are rated for.... Dont cheap out with something that "may
work" (or not) off e-bay because its is cheap and find out later results is very expensive.........

http://www.delcity.net/productsearch?se ... rs&x=0&y=0

http://www.waytekwire.com/products?pSea ... rs&sc=1366

Also search the sites mentioned above for fuses and fuse holders...... MANY options.....

Dale

[Shadow Catcher]

After having a cutoff switch fail I switched to a Blue Sea

[abqlloyd]

The max VOC on my panel is 35V. I have an inline fuse. I'm more interested in a cheap cutoff.

[abqlloyd]

ImageUploadedByTapatalk1418696693.432560.jpg (116.86 KiB) Viewed 1899 times

I bought these in September.