new LED array help

[nitjt]

I built an array and now about half 45 leds are out can't find a short but I have leds on the same string some are on and some off I am using meanwell Ds to drive XP leds. I have one whole string 14 LEDs that are on but very very dim I mean just barely on.

[SWINGRRRR]

Did you open the ELN's and set SVR2? What are you feeding the dim circuit?

[nitjt]

I have been using my apex vsp to dim everything worked great for a couple of months.

[nitjt]

I just can't figure out why on the same string I have 12 out of 14 LEDs out. The other two are bright as they can be. When it test each led with a battery I can't get the ones that don't come on to light up. Are they just burnt out? how can I know?

[SWINGRRRR]

Im no expert, but if they are not lighting with a battery, they are problem gone. Something went very wrong somewhere and burnt them out.

[mike_cmu04]

I thought 13 led's was the max on a meanwell?

[kcress]

Disconnect the ends of the string. No power. Try your battery test on each and what do you get?

Also with NO POWER use a magnifying glass and look in the little dome. All that blown will appear markedly different from ones that are normal and work.

How exactly were your 45 LEDs wired up?

[nitjt]

I have 7 strings of 14 XP-E and XP-G LEDs driven by Meanwell ELN 60-48D drivers. They are wired in series I thought if they were wired in series if one went out the entire string would go out?

[der_wille_zur_macht]

I thought if they were wired in series if one went out the entire string would go out?

Only if they fail open. If they fail closed (i.e. short) the rest of the string will continue to operate.

I'd look very carefully for shorts to heatsink(s) and/or other metal items. In a few other threads where people reported failed builds with partially lit strings, there were multiple shorts to the heatsink, allowing current to bypass some of the LEDs in the array.

[nitjt]

How do I check for a short to the heatsink? Some of the glass domes do look different so I guess I have blown some of the LEDs. My biggest concern is an entire string that will barely light up very very dim? What's up with that? I just don't know where they went bad I had them working great for about 2 months with no problems.

[SWINGRRRR]

How do I check for a short to the heatsink?

Use your DMM, 1 prong on the pad LED and 1 on the heatsink. Test for continuity. "Ohm it out."