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stapler causing lights to blink

stapler causing lights to blink

stapler causing lights to blink

(OP)
Here is the situation, 75kVA 480/208 3-phase transformer (lightly loaded) feeding panel board ~10 ft away. On one branch circuit ~20' away is loaded with a desk type electronic paper stapler. The stapler goes WAP! and the t-8, electronic rapid start luminaries blink. customer is annoyed. Would a "plug in" ~300V ac cap (in an adjacent outlet) do any help? Adding series inductance to the stapler circuit (intuitively to me) would compound the problem?

Thanks in advance

RE: stapler causing lights to blink

I am suspecting that it isn't the current draw from the stapler but is in fact a single horrendous noise spike that the poorly designed ballasts are reacting to.

I would be interested in seeing what happens when you plug the stapler into the same outlet through a 100ft extension cord.

But alas the first thing to try, as a solution, is to plug the stapler into one of those so called "surge protector" power strips.  This should clip off the bulk of the spike/s and it may be enough to stop the ballasts from reacting.

Keith Cress
Flamin Systems, Inc.- <http://www.flaminsystems.com>

RE: stapler causing lights to blink

(OP)
smoked, I tend to agree. When in the room and the stapler goes off you can almost feel the ringing of an impulsive spike. The extension cord (distributed transmission line pi network of series L and shunt C and strip surge protector will be interesting to try.

However, at this facility the fire inpectors go high order when they see extension cords ("as a substitute for permanent wiring"). Not to mention a homemade plug in capacitor! Just try and explain that to one of those bone heads.

And also my experience with high end service entrance surge suppressors have been that the MOV's degrade and are only good for a finite amount of hits. I assume the strips would be similar.

RE: stapler causing lights to blink

Yeah the strip MOVs will wear out eventually.

I thought that circuit breaker-ed power strips were allowed these days.  I have had inspectors look at them just to make sure they where CB'd then dropped them and moved on.

Perhaps the ones with 3 ft cords might fly?

I couldn't even operate without them.  My three desks probably have 35 plugs each.

Keith Cress
Flamin Systems, Inc.- <http://www.flaminsystems.com>

RE: stapler causing lights to blink

I think the 100 ft cord was intended as a test, not to leave a huge coil under the desk full time. The plug in surge suppressor could also be tested. If successful and unacceptable for full time use, wired in receptacles incorporating surge suppression are available.

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