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Posted By: Zapped Pulse-Start MH - 04/04/08 02:52 PM
Just wondering if any of the lighting gurus here have an opinion on pulse-start metal halide lamps and ballasts.

I have a client with tennis courts being lit by a dozen 1000W Metal Halide fixtures. There are 6 lights for each of 2 courts, and they are activated by a key switch for each court.

The system I installed about 5 years ago was completely automated, and uses standard 1000W metal halide kits. A member would rotate a keyswitch, then remove their key. This would activate the lighting for one hour on the court they were using.

The client wishes to change the system so that the members key stays in the switch as long as they wish, then they remove their key when they leave (which deactivates the lighting).

They wish to have the lighting at full brightness quicker than the current warm up time (which is 5 or so minutes with the standard MH kits).

Do you think that pulse-start MH kits are going to handle this type of application well? Do you foresee any problems that I should make my customer aware of? This will be a considerable investment for this community, and, as always, I'd like to let my customer know exactly what they are getting into.

Thanks in advance for your advise!

Posted By: togol Re: Pulse-Start MH - 04/06/08 04:15 PM
I have had very little experience with the Pulse Starts but what I do know is that they start faster, but restrikes are about the same, ....since that depends on the temp of the arc tube..!
there is one Mfr. that the 3 supply houses here seem determined to buy from and that would be Venture.... a practice that tends to keep the price higher IMO, and delivery times longer

I was also told that existing circuits could become overloaded when retrofitting with Pulse Starts, because of higher starting currents, so your breakers may be undersized !!

but aside from the special Lamps, Sockets, and Ballasts, they offer pretty much the same light output..
Posted By: Tom Re: Pulse-Start MH - 04/06/08 11:48 PM
PSMH lamps put out more light per watt than standard. You can usually replace a standard 400 watt MH with a 320 PSMH. My experience on restrikes is they are a couple of minutes faster.

As for higher current draw on startup, the PSMH ballast does draw more current than a standard MH ballast. However, the starting current is less than the operating curent, so there would be no problems at startup.
Posted By: Rewired Re: Pulse-Start MH - 04/08/08 10:41 PM
The retirement home I started my electrical apprenticeship wiring up had a whole slew of 100W PSMH fixtures outside for perimeter lighting.. They worked well BUT we found that a momentary power interruption caused the line current to almost double while the ballasts were trying to re-ignite the lamps, causing the breakers feeding the lighting to trip open.. I don't know if this was just an isolated case with only one manufacturer of ballasts, but it may be worth checking into.

A.D
Posted By: Scott35 Re: Pulse-Start MH - 04/10/08 02:39 AM
Zapped:

The PSMH Lamps should achieve full brightness faster than the Probe Start ones, and the "Hot Re-Strike" time is drammatically shorter than the Probe Start Lamps' >10 Minute hot re-strike time.

FYI: - per CEC Title 24, Part 6:
Metal Halide Lamps of 175 Watts and less (I think 175, or it is 250 watts) are to be Pulse Start types - for new installations or lighting alterations.

Some day this will probably cover _ALL_ Metal Halides.

Scott
Posted By: Zapped Re: Pulse-Start MH - 04/14/08 09:49 PM
Thank you for your advise and input gentlemen. As always, it's very much appreciated.
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