Sodium flood light off during large motor starting

[shkim2000]

I have traced the reason why sodium flood light is off during large motor starting. When large motor is starting sodium flood light is turned off and it is back on after starting/getting stable condition of motor.
Do anybody know why it happen and how I can make remedy to it ?

 

[edison123]

Voltage drop due to initial inrush current during motor start. Your power supply should be strong enough to reduce such voltage drops. Or try a separate lighting circuit and not connect to power circuit.

 

[RRaghunath]

You have an option the HPSV lamp control gear - ballast to select a lower voltage tap.

However, if the voltage tap selected happens to be lower than the normal system voltage there is a danger of overheating / failure of the ballast. This method is used widely for the street light fittings at the tail end of the circuit.

 

[jraef]

Another option is to reconsider the method of starting your large motor. If you are not already using a reduced voltage start, consider doing so. If you already have a Y-Delta starter, you can consider changing to something more adjustable like a solid state starter so that you can find a soft start setting that reduces the voltage drop while still allowing the motor to start..

"Venditori de oleum-vipera non vigere excordis populi"

 

[shkim2000]

Thanks Gents.

Motor starting method is Star-Delta starting but problem is not created by voltage drop. It seems that harmonics kills ballast during starting. In this condition, is there any other solution against problem ? At the moment starting method can not be changed.

 

[dpc]

How do you know it isn't voltage drop? A wye-delta starter shouldn't be creating significant harmonics.

 

[edison123]

what harmonics ?

 

[buzzp]

Measure the supply voltage during the motor starting (preferred to use scope with adequate probe for the voltage). This should reflect a voltage below the voltage required of your lamp ballast to remain on. This is what all the previous posts have been trying to tell you.

A decent meter should catch the voltage dip, in most cases, if an oscope is not available.

 

[jraef]

I doubt it is "harmonics" from a Y-Delta start, but it may be a transition spike from when the starter switches from Y to Delta. That can cause a severe current and voltage spike depending upon circumstnaces, Do a keyword search in this forum for "transition spike" and you will see a number of threads on this subject.

"Venditori de oleum-vipera non vigere excordis populi"