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Motor Start HPS lighting dip 1

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elmatador

Electrical
Jun 10, 2009
22
Hi Folks,

I am carrying out a motor starting study. I have a 3100HP 4000V motor being started across the line at a system voltage of 4160V. Motornis a centrifugal with closed valve start. The main transformer is a 12MVA transformer. The voltage dip is 13% for 1.5s. This dip is also seen on the 480V bus. I am trying to figure out if this dip would extinguish the High Pressure Sodium lights. I have researched as much as possible and the only thing I could find is that these types of fixtures can handle +/-10% variation in voltage. I am unable to find any literature that states the voltage dropout value for HPS ballasts. This fixture is NOT the auto regulating type. Its a basic 277V HPS with 0.9pf.

Should I be concerned? All other equipment can handle -15% variation. My main concern is the lighting. Please chime in. Thanks.
 
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If we shall follow the AEL [American Electric Lighting] HPS Servicing Guide-see:
then a HPS lamp may function between +/-15% and +/-10% of rated voltage.[TABLE 1: HPS LAMP DATA].
On page 16 is stated:
"Extinction Voltage: All power systems are subject to dips in line voltage that normally are around 10%, but occasionally can reach 20% to 30%. The ballast should be capable of riding out these dips without extinguishing the lamp."
 
Thank you kindly for your response. I managed to get the crouse hinds ballast data and their dropout voltage is 80%. So should be safe.
 
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