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Posted By: ctolbert Huge amount of Christmas Lights - 10/18/02 11:26 AM
I feel like I'm in that movie "Christmas Vacation." I was thrown a project that is huge and already started. I would love some comments about the direction it's heading.

--64 light strands (700 watt 120vac incandecent)
--600 amp feeder with 16 x 30 amp breakers allocated for above strands.
--4 strands per breaker
--each strand controlled on/off with 10 amp omron micro relay with a 2 times a second switching rate.
--relays controlled by plc in predetermined pattern.

My biggest concern right now...is the switching speed and the inrush from the lamps as they are switched.

Any comments would be appreciated,

Thanks,
Carl
Posted By: Pearlfish Re: Huge amount of Christmas Lights - 10/18/02 04:38 PM
If the inrush becomes a problem, have your programmer input a 20+ millisecond delay into selected rungs. It will be almost imperceptable to the eye. If you have a large number of rungs, the lights will "sweep" on and still look nice!

[This message has been edited by Pearlfish (edited 10-18-2002).]
Posted By: Scott35 Re: Huge amount of Christmas Lights - 10/18/02 07:36 PM
Interesting subject!!!

Could you add some more data so we can have a better understanding of everything?

Stuff like System type [1 phase, 3 phase], exact rating of each lamp [or lamps if various types], inrush level or cold Resistance level, flashing in sequence, randomly or all at once, overall length of circuits / feeders / subfeeds, available KVA, switching relay's duty rate and other specs, and do the lamps have to be at 100% intensity when on, or can they drop to 90% intensity.

Scott S.E.T.
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