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solar set-up fuse sizes
#11
Regarding the circuit breakers, I was not trying to say that only the best and priciest is acceptable.


I did want to relate my experiences with the more budget friendly circuit breakers that I bought, and still employ.

If my  '140 amp' circuit breaker tripping after 5 minutes passing 100 amps, fried the diodes in my alternator, it most certainly would not be worth the 14$ I 'saved' buying it, vs the more expensive Bussman brand.  I got lucky. Very lucky, and perhaps my Alternator diodes having been so stressed with that significant load dump event, will fail prematurely when murphy decides to poke his evil head up,  or perhaps some stray AC current is slowly eating away my engine computer's magic smoke containing components as I revel in ignorance at that possible occurrence.

My 30 amp CB on my solar controller getting warmer than surrounding wiring and general area, passing just ~9 amps, certainly does not make it unsafe or incapable of protecting the wiring, but that heat is indicating some loss. Oversized wiring routed in the shortest possible circuit from panel to SCC to battery is an attempt to minimize loss/voltage drop to extract as much juice as possible form the sun, so the these thermal circuit breakers have to basically waste wattage as heat and negate some percentage of effort to minimize voltage drop/ resistance.  A hard pill to swallow.

My SCC is rated for only 25 amps, and its manual calls for a 30 amp fuse, and I am using it on  4awg wiring than can safely pass some 80+ amps continuous.

But if, if I maxed out my solar controller at 25 amps, and the 30 amp circuit breaker tripped after several minutes of passing 24.5 amps, it could destroy my solar controller,  so the ~15$ I saved once again, would be a false economy, if that were to happen.

Replacing the '140 amp' CB with a quality Bussman brand, and replacing the 30 amp with better quality, is certainly more costly than having just bought the bussman brands initially.

Circuit protection devices are not a great place to save money.  I regret my frugality, yet the only real consequence so far is to my confidence in my system, and perhaps a few watts lost as heat.  A few watts lost as heat, is not very consequential, but taking out my alternator or Solar charge controller, would be more than just inconvenient as I don't have the luxury of throwing money at problems.

So when someone is setting up a new system, I'd prefer to eat some crow and admit/relate my mistakes and regrets about my choices of the products I chose in the past when i had less experience and was less edu-muncated. Choices based on price and whether they had 'free' shipping. 

I fully realize Spending other people's money is easy, but I'd prefer others benefit from my hindsight, rather than make my same mistakes.

All over the web, on forums, there is someone who finds a product significantly cheaper than somewhere else, and they want confirmation that the product is just as good or simply good enough.  They will get dozens of replies and the thread dies only once the answers given are what the original poster wants to hear.  Usually a few 'works just fine' stories by someone without the ability or tools or aptitude to determine the performance, or make that judgement, are all it takes.

On some specific Automoticve forums, people are buying wal mart's value power battery that is basically half the price of the same size regular starting battery.  It seems the only people who respond to the threads about these batteries claim they are still 'going strong'

But are these people seeing how much voltage the battery is maintaining cranking their 140 amp starter?  Do they have any idea how much capacity the battery retains of its original capacity?  Do they know whether one of the plates is dangling by a sulfated thread waiting on a signifiant bump to break off and short out a cell rendering the battery useless?

No.  To them if it still starts the vehicle( which takes so very little of a battery's ability) that it is 'still going strong' and that their purchase and they themselves, are extremely wise, and they break their arms patting themselves on the back, and expect others to do so too.

This is just a general rant at the nature of humans, not directed at any individual on this, or the 'other' forum.
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#12
Well, I can see the e-mail writer's point. Humans seek labels that identify our social position, and use sophistry to justify the snobbery.


'I knew a guy that saw an RV burn down once' = 'You will die in a horrible fire if you don't get Blu Sky.'

There's low cost to no-cost ways of doing things, that are perfectly safe. They just don't have the label.
Sometimes dweller in 237k miles '07 Grand C-van w/ a solar powered fridge and not much else
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#13
cheap things tend to be cheap,a $20 item to protect a $500 item seems like a good investment to me
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#14
a cheap or free item's even better Wink
Sometimes dweller in 237k miles '07 Grand C-van w/ a solar powered fridge and not much else
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