Randomblame
Well-Known Member
The defective COB should be the reason! Did the defective string work with the other driver? You can sort out the defective COB and try to fire up the other three. If it's working you did find the culprit.Alright so I swapped the drivers over and both drivers lit the working string of lights so the drivers are fine. I went ahead and disconnected the fourth light from the working string and starting subbing lights from the other string one at a time and found that only 1 of 4 lit. Thinking this was odd, I removed all the cobs from the holder and took the 3 that didn't light and put them in a holder from one that worked... aaaand .... they all lit. So as I suspected there's some bad connections between the tabs in the holder and the cobs for some reason(tried moving the wires around to make sure it wasn't a loose wire going into the holder).
I did notice that the small metal tabs seemed to be slightly pushed to the side, but I don't think this was caused by me as I attached them all the same, and have had no problems in the past building other cob fixtures. Not sure if maybe they got bounced around in the mail and bent and I didn't notice or what, but that seems to be the issue. I haven't tried using the ideal holders over the bjb ones but now I'm wondering if maybe those ones have a better build quality/QC ?
On a side note, while testing all the cobs I noticed that one of them had 3 or 4 rows on one side not working. To be honest I have never really checked all my other cobs for this since they are so damn bright, but is it relatively common to have dead rows?
COB's are sensitive!
You only have to slide over the carpet and touch a COB, the rest will do the electrostatic charge. Better be earthed with an antistatic bracelet, like the PC builder have.
Ceramic COB's are the most sensitive and also break easily like egg shells!
A narrow, not visible hairline is already enough to break the circuit inside the COB.
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