BJB holders voltage spec is too low for series configuration

BOBBY_G said:
note that although all the BJBs have similar design, apart from the cxb30xx anomaly they are all rated at 60V except for the clu05X... which is a 100V chip by design. the rest are all 36-50V.

so maybe the holders can handle 150V or more but they never felt the need to test/certify for it until they had a chip of high voltage

i wish there were ideal chiploks for the clu05x.......
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Not to mention they also say this about the 3070 holders:

Approval: additional cULus (75W /250V)
cULus file no.: E-345385

Personally I'm not sweating it. Maybe they didn't want to shell out for UL testing, since it's the same materials, same design, different rating.

Link http://www.bjb.com/index.php?pid=373368&lid=4
 
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BOBBY_G said:
just watch your torque on those bolts
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Hi bobby_G
i cant find any informations in the datasheet from citizen what Max. torque i should use for screws to hold the cob on the heatsink(without cobholder).
I have a tool with a torque range from 0,3Nm to 1,2Nm. Should i select 0,3Nm?
 
BOBBY_G said:
the only other thing i hate about the BJBs is it appears the wire connection is permanent unlike an ideal which can be removed by putting a paperclip in the other hole
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huh? used a few types of bjb's and haven't had this problem?
have you tried multiple times to remove the wire at all since.....? :peace:
 
trying not to break it and just yank on it but its not like an ideal where you can stick a paperclip in the other hole. how do you do it?
 
guys, what are you afraid of? no disrespect , but about COB everybody is like atomic engineer, but when it comes to COB holder, you are like dummies

BJB holder can handle 3A / 150V

so it can also handle 1,5A / 300V

it is about overall load wich can generate to much heat and cause damage. There is no sparks with 300V, there are strong connections in your circuit and the only one spark can be in your driver or timer when turning on/off and there is protection for that.

Generally lower voltage and higher amps generates much more heat than higher voltage/lower amps, because it is amps that generates electron motion which generates heat!

This is the reason why we have high voltage conduction which alows higher power distribution with smaller diameter conduction.
 
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kvakos said:
guys, what are you afraid of? no disrespect , but about COB everybody is like atomic engineer, but when it comes to COB holder, you are like dummies

BJB holder can handle 3A / 150V

so it can also handle 1,5A / 300V

it is about overall load wich can generate to much heat and cause damage. There is no sparks with 300V, there are strong connections in your circuit and the only one spark can be in your driver or timer when turning on/off and there is protection for that.

Generally lower voltage and higher amps generates much more heat than higher voltage/lower amps, because it is amps that generates electron motion which generates heat!

This is the reason why we have high voltage conduction which alows better power distribution with smaller diameter conduction.
Click to expand...

So at 1400mA 3 cobs in series is ok with BJB holders? Well obviously more than that but 3 is what I want because that's what fits my plans.
 
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:neutral::-|:|

It is about voltage.

Exceed voltage rating at your own risk.......

kvakos said:
guys, what are you afraid of? no disrespect , but about COB everybody is like atomic engineer, but when it comes to COB holder, you are like dummies

BJB holder can handle 3A / 150V

so it can also handle 1,5A / 300V

it is about overall load wich can generate to much heat and cause damage. There is no sparks with 300V, there are strong connections in your circuit and the only one spark can be in your driver or timer when turning on/off and there is protection for that.

Generally lower voltage and higher amps generates much more heat than higher voltage/lower amps, because it is amps that generates electron motion which generates heat!

This is the reason why we have high voltage conduction which alows higher power distribution with smaller diameter conduction.
Click to expand...
 
guod said:
so it can also handle 450A / 1V
and also 0.001A / 450000V

have a nice day...
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What he said makes sense.what you said does not.it is in fact high amps where sparks occur and wires melt.
What i always wonder is if we have 5 x 36v cobs wired in series on a 1 amp load does the ideal or bjb holder see the entire current or just what the cobs are using like in this case 36v or 35.5 whatever the cob is seeing? I just assumed someone put a volt meter in line between the 2 cobs in series to check this but maybe not? Seems like alot of people here are just guessing at what is actually running through the holders ?
 
High voltage increases the distance electricity will arc. The connectors are exposed on the underside of the BJB holder so too much voltage and the current will arc to the heat sink.

It is possible to fill in the well holding the wire connectors with liquid electrical tape... but that's not advice, just an observation.
 
sixstring2112 said:
What he said makes sense.what you said does not.it is in fact high amps where sparks occur and wires melt.
What i always wonder is if we have 5 x 36v cobs wired in series on a 1 amp load does the ideal or bjb holder see the entire current or just what the cobs are using like in this case 36v or 35.5 whatever the cob is seeing? I just assumed someone put a volt meter in line between the 2 cobs in series to check this but maybe not? Seems like alot of people here are just guessing at what is actually running through the holders ?
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in that case, there is 36v on every cob/holder separate.

Current spark = yellow ,voltage spark = blue , you will never have yellow spark at already closed circuit, you can only have blue because it is high voltage that allows you have long sparks.

to RAHZ : in your case you have to have exposed wire and exposed uncoated/ ungalvanised heatsink and high voltage over 1000V, than you can have about 1mm long spark between pure metals. You have rubber insolation on wires and i supose BJB dont have any exposed metal, everything should by covered by plastic except COB contacts. There is some rule how long can the spark be. I thing that it is something like 10 000V = 1cm long spark that can spontaneously occur between conductive material.

Insolation like plastic and rubber can exceed voltage up to 1000V or more. Coated coils have coating with thickness 0,001mm or less and can outstand that coltage too.

quote: so it can also handle 450A / 1V
and also 0.001A / 450000V
this is really bullshit example, we are thinking about 20v-400v here.


Does have anyone close-up photo of BJB?
 
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sixstring2112 said:
What he said makes sense.what you said does not.it is in fact high amps where sparks occur and wires melt.
What i always wonder is if we have 5 x 36v cobs wired in series on a 1 amp load does the ideal or bjb holder see the entire current or just what the cobs are using like in this case 36v or 35.5 whatever the cob is seeing? I just assumed someone put a volt meter in line between the 2 cobs in series to check this but maybe not? Seems like alot of people here are just guessing at what is actually running through the holders ?
Click to expand...

100mA can be lethal..

fatal_current.gif
 
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