# LED Harmonics



## Cletis (Aug 20, 2010)

Does anyone know how LED drivers affect harmonic currents in 3 phase systems ?? If so, links?


----------



## Cletis (Aug 20, 2010)

WHOA!!! 

http://www.youtube.com/watch?v=toc5pveyRCA


----------



## LegacyofTroy (Feb 14, 2011)

So , I watched video......what are the negative effects?


----------



## Cletis (Aug 20, 2010)

LegacyofTroy said:


> So , I watched video......what are the negative effects?


Burning up nuetral wires and not sleeping (more time to post on et for me)


----------



## LegacyofTroy (Feb 14, 2011)

Maybe, do you think neutrals could be that effected? Load seems minimal.


----------



## Cletis (Aug 20, 2010)

Thats what i'm not sure of yet. Say you had all Metal Halides and went LED your going to lower your total load around 75%. So, if you had a bunch of branch cir. at 15 amps all day your going to drop that to around 3.5 amps per instead. Are harmonics bad when your already nearing max of the circuit or are harmonics bad even at low loads ??? That's the question


----------



## LegacyofTroy (Feb 14, 2011)

Less is more?


----------



## 10492 (Jan 4, 2010)

You have no idea what harmonics are, and how they effect anything.

Call a real electrician if you feel you have a problem.


----------



## LegacyofTroy (Feb 14, 2011)

I'm pretty good with harmonicas........


----------



## mbednarik (Oct 10, 2011)

I would not think it would be any different than replacing with a fluorescent product.


----------



## bennysecond (Jan 18, 2013)

Here is a little bit:

http://www.eagle.org/eagleExternalP...armonicsinElecPowerSystems/Pub150_ElHarmonics :thumbsup:


----------



## Lighting Retro (Aug 1, 2009)

The man has an accent, so he must be smart


----------



## Electric_Light (Apr 6, 2010)

Cletis said:


> Does anyone know how LED drivers affect harmonic currents in 3 phase systems ?? If so, links?


Like any other bulk-storage bridge front end power supplies. Fluorescent ballasts and many newer desktop computer power supplies is built with active PFC which also serves as a regulator. (maintains perfectly constant wattage over varying line voltage unlike older ballasts)

A few percent relative to the total kVA demand won't make a squat of difference as the case with fluorescent ballasts. 

Ballasts used in commercial buildings are rated to give > 0.90 PF. They usually represent a significant portion of loads on a wye system. So, ideas that apply to fluorescent ballasts is applicable to LED power supplies.

You'll need 2kVA transformer capacity per kW unless you get a k-13 to k-20 rated one.

100kW at 0.7 PF is 143kVA.
200kVA tranny at 30% derate is 140kVA.

If you use all active PFC power supplies, you can get away with a 125kVA one.


----------

