Running BJB holders above the 3A / 150V rating?

nogod_

nogod_

Well-Known Member
Agreed, i never suggested running those chips in parralel on that driver, only the cc/cv driver he linked initially before he edited his post.

As to the other bit, there have been a few threads addressing the voltage limitations of various cob holders re: high voltage strings, and your point has never been raised to my knowledge (full disclosure: i am not an electrician nor an electrical engineer in any way). So you're saying the voltage passing through the holders is only 36v and we would have to stick a 160v cob in there to go over spec? Does that mean we can wire as many quantum boards as we want in series and the guys selling them have been lying to their customers?

MAJOR GANJAH said:
The HLG-240H-C1400 is a constant current driver with minimum output voltage of 89V, which means in a parallel circuit each chip would be under 89V of tension at least, way above the optimal voltage for running them. If you put them on series they will be supplied with about 36V and 1.4A current on each chip, which means that each holder will be subject to this exact tension. The only object in this circuit which will be subject to the 179V tension will be the driver. You have to think of this circuit as a river, each chip is a 36V waterfall, and the driver is a pump raising the water all the way back to 179V lake. Between each chip with the same exact electrical properties (i.e resistance) the fall will be always 36V steep, the only point that connects to the extremes is the driver.
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MAJOR GANJAH

MAJOR GANJAH

Member
nogod_ said:
Agreed, i never suggested running those chips in parralel on that driver, only the cc/cv driver he linked initially before he edited his post.

As to the other bit, there have been a few threads addressing the voltage limitations of various cob holders re: high voltage strings, and your point has never been raised to my knowledge (full disclosure: i am not an electrician nor an electrical engineer in any way). So you're saying the voltage passing through the holders is only 36v and we would have to stick a 160v cob in there to go over spec? Does that mean we can wire as many quantum boards as we want in series and the guys selling them have been lying to their customers?
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Sorry, I did not saw the edit.

Regarding the second part, the voltage does not pass trough the COB, the cobs are subject to it, just like tension in a string. Voltage is a measure of potential, which is always a measure off differences in energy, if you use a multimeter to measure what is the voltage between both terminals of a cob it would read "36V" (- or +). I was reading another thread about it and they were arguing on exactly this point.

https://www.rollitup.org/t/bjb-holders-voltage-spec-is-too-low-for-series-configuration.912573/

For some reason the voltage limit of the holder is based on driver voltage and no one there could figure out why, and tbh I can't think in any answer to give you either.
 
CobKits

CobKits

Well-Known Member
MAJOR GANJAH said:
For some reason the voltage limit of the holder is based on driver voltage and no one there could figure out why, and tbh I can't think in any answer to give you either.
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because if your driver and your heatsink are both grounded the full voltage exists between the + terminal of the first cob/cob holder and ground
 
Boatguy

Boatguy

Well-Known Member
CobKits said:
well sort of.

high voltage can arc easier. think about lightning, or a spark plug
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Even lower voltages can arc if offered an easier path to ground. I was just saying that amps are more of a concern with wiring/wire size.
I would bet 25v at 18amps would fry that holder instantly, alternatively running 300v at 1.5a the holder would probably work fine.
I am in no way suggesting anyone run 300v through those holders, but exceeding voltage rating by alittle with lower amperage isnt a big deal
 
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MAJOR GANJAH

MAJOR GANJAH

Member
I have a question. Can a BJB holder be used with four clu048 at 1400mA ? That would be about 148V, which is pretty close to the 150V limit. Is it safe? Or should I buy ideals instead? The lack of adapter ring and less holes make the BJB much more attractive.
 
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