Dimmer Pack blowouts

[Grottfather]

I am a Tech director for 2 theartres in the southern part of VA.
in my outside theartre i am runnin 5 Dimmer packs with roughly 25 lights. my issue is for some reason the fuses blow almost daily on one of them. each time its a different pack. i am using the Levitron dimmer packs as well as for fuses used 250V 10Amp. Any Ideas why this is that they are blowing?

Thanks,
Tony

[YHStechjordan]

Clean them? That worked for me. How often do you clean them?

[Pie4Weebl]

for clarification, when you say 5 packs do you mean 5 dimmers, or 5 units with say 6 dimmers in each?

Also are they all tied into the same power circuit, there could be an overload there.

[beam_1973]

Originally Posted by Pie4Weebl

for clarification, when you say 5 packs do you mean 5 dimmers, or 5 units with say 6 dimmers in each?

Also are they all tied into the same power circuit, there could be an overload there.

Would the dimmer fuse blow though if the overall supply circuit was overloaded? I would have expected the breaker on the main supply to trip before the dimmer fuse (provided the fixture on the that dimmer channel is not rated/operated on a load greater than 10 amps)??

[zac850]

OK, Since you said the fuse is blowing, I am going to assume you mean the little fuse inside the dimmer pack is blowing.

The fuse is blowing because you have to much power running through the dimmer. Low end NSI gear is good for 600 watts per channel. If you have 5 dimmers and 25 lights, your packs can't handle that much power.

So, for the time being, see what each dimmer is rated to. Then see how powerful the lights are that your using. Then unplug all but what the dimmers can handle.

For a fix, go get more dimmer packs. You will need to verify that you have enough power available in the building, and then possibly need to hire an electrician to wire up some outlets for you.

If your blowing fuses, don't just replace the fuse. Lower the load on the dimmer. The fuse is blowing for a reason.

[beam_1973]

Originally Posted by zac850

If your blowing fuses, don't just replace the fuse. Lower the load on the dimmer. The fuse is blowing for a reason.

And because its happening on different dimmer packs each time, you probably have more than one dimmer channel overloaded.

Also try the fixtures that are patched to those tripping channels on other "normal" channels (or get them checked by qualified person) to make sure you don't have any dodgy wiring that is causing the trip.

[BillESC]

Rather than make suppositions, please tell us which model NSI packs you're using and the wattage of the fixtures patched into them.

The more information you supply, the better the reply will be.

[ship]

Some clarification also if possible. By way of five dimmer packs, do you mean five individual dimmers in one pack or a rack of five say of eight way dimmer packs all having the same problem?

On each dimmer is also five lighting fixtures or given it's normally eight dimmers per pack how are these 25 lights distributed including their wattage?

Ditto on the model of the dimmer pack and wattage of the fixtures.

Also how many phases are feeding the pack / what type of power service is feeding it such as three phase wye (120/208v), single phase three wire (120/240v), or single phase (120v). Might it be blowing fuses powered by one specfic phase of power or all?

What's the voltage coming from the service panel than as a second reading at the dimmer pack? Also verify both voltage readings on all phases not just in reading the neutral to hot but also hot to ground.

As a general question and always, when is the last time this/these dimmer(s) had a service call?


"fuses blow almost daily on one of them. each time its a different pack".
Again with telling what loading is on what circuit/dimmer, at what point are they blowing, when turned on or at some point say when that dimmer is at full. This at full during a show's run but not all the time? What type of lighting control do you have also if fuses are blowing at random on dimmers - two scene pre-set where say an overloaded dimmer might not be at full every night or computer scene based where it's the same dimmer level every night? More than one fuse per just about every night at a time or only one, and frequently one of a few select dimmers but not per say all the dimmers/dimmer packs out of five?

[kingfisher1]

I believe it was stated that they were levitron not NSI. I assume the fuses you are using are the correct fuses. should the fuse contact not quite line up or something you may get uncostumary resistance and heat buiding up. just a though

[BillESC]

NSI is the theatrical dimming division of Leviton. Leviton itself only produces commercial and residential wall dimmers.