Not to seem alarmist (well at least until I came to know that roof panels can operate at 400Vdc - that was a wake up call and there have been roof panel fires from failures caused by internal shorts, kakapo's, baboons and aerial object impact damage, hence the insistence by the OZ Civil Servant to install manual breakers up on the roof near panels where you cant reach - nice), I think that a return to basic first principles
is needed and methods originally employed in dc high current systems. Yet I shall only deal with ELV systems 12,24,48Vdc in their ascending severity. For DIY IMHO the jury is out on whether 48V level is worth the risk - its 16x the destructive energy to contain.
At 12/24Vdc levels there is and abundance of well proven devices, tried and tested over decades from the auto industry, readily available provided they are suitably employed. KISS.
But some test rig proof is needed due to the very much greater ampacity and AIC (20kA) needs of Lion battery packs over traditional LABs.
I am aiming for a 500A sc rig first in my detached garage at least to get some experience on monitoring current interruptions at this level. I can record electrical graphs, temperature rises and physical effects, flash damage etc at say 32A level devices (tbc). I have to see what video equip I can muster.
Any help would be much appreciated and acknowledged
OBTW I hope to encompass knowledge from the US off-gridders/systems, ABYC boaties, OZ Rules and (baby in the party BS7671 Regs) so as to get a cross boundary consensus of good practice, after all the Sun goes round the World.
eg Class T fuse$$$$ vs NF IEC fuse$$$ (aka HRC) or fusible link (a piece of thin wire)
$
US ind breaker $$$$ vs IEC breaker $$$$ or knife switch (in use by billions in the FE)
$
Well Guys I am building a test rig to throw some heavy current at these devices cos I simply dont believe all the hype and BS surrounding this new Solar fashion - but the physics and engineering behind the dc protective devices is not new. High ampacity dc systems have been around for a century in such industries as electroplating, traction (mines, trams, underground rail, telephony exchanges LAB storage UPS, industrial UPS systems, etc.) The technology is out there but covered in proprietorial mystique $$$$). The average DIY Joe only has catalog-claims to go on and little understanding of the nature of electrical protective devises - as evidenced by the squinching vids propounded by said amateurs OMG. Also said Joe (you gotta admire his enthusiasm) simply doesnt have the facilities to test the safety devices and may suffer when a catastrophic fault occurs (even the big kids get it wrong (cf Arizona Surprise incident).Not to seem alarmist (well at least until I came to know that roof panels can operate at 400Vdc - that was a wake up call and there have been roof panel fires from failures caused by internal shorts, kakapo's, baboons and aerial object impact damage, hence the insistence by the OZ Civil Servant to install manual breakers up on the roof near panels where you cant reach - nice), I think that a return to basic first principlesis needed and methods originally employed in dc high current systems. Yet I shall only deal with ELV systems 12,24,48Vdc in their ascending severity. For DIY IMHO the jury is out on whether 48V level is worth the risk - its 16x the destructive energy to contain.At 12/24Vdc levels there is and abundance of well proven devices, tried and tested over decades from the auto industry, readily available provided they are suitably employed. KISS.But some test rig proof is needed due to the very much greater ampacity and AIC (20kA) needs of Lion battery packs over traditional LABs.I am aiming for a 500A sc rig first in my detached garage at least to get some experience on monitoring current interruptions at this level. I can record electrical graphs, temperature rises and physical effects, flash damage etc at say 32A level devices (tbc). I have to see what video equip I can muster.Any help would be much appreciated and acknowledgedOBTW I hope to encompass knowledge from the US off-gridders/systems, ABYC boaties, OZ Rules and (baby in the party BS7671 Regs) so as to get a cross boundary consensus of good practice, after all the Sun goes round the World.eg Class T fuse$$$$ vs NF IEC fuse$$$ (aka HRC) or fusible link (a piece of thin wire)
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