lights going off when opperating3ph door / machine

[Simon-0116]

might be in wrong section so be kind. got a warehouse/ fabrication unit with a mixture of 150w low bays and 250w high bays either metal a-xline or merc bulbs and 1x 400w son flood light. they are all on variouse phase. when they operate a 3 phase press machine or shut 3 phase door some of low bays plus the flood go off. not every time but getting worse. why. everything tight, insulations on all cables good, same voltage on all phases, drops slightly when machine / door used. any ideas, or is it a sign of the lights getting ready, been up about 15 years. any help.

 

[telectrix]

depends on how low the voltage drops. below 220/phase could cause this.

 

[Knobhead]

Where abouts is the job? More to the point where are you?

Drop me a PM.

 

[Bobster]

How low does the voltage drop? What's the Kw loading of these 3phase machines?

 

[Pete999]

The installation may have just been added too over the years with little regard to a proper design, yep sounds like volt drop to me

 

[Guest111]

As above volt drop,try measuring voltage on lighting circuit then get someone to run a machine or open a door and see what it drops to.

 

[Engineer54]

I wouldn't mind betting those affected light fittings are the furthest away and/or have the most fittings on a circuit from the DB too?? lol!!

As Pete said, a common result of adding and adding again without taking in to account existing circuit design etc....

 

[Simon-0116]

hi probably the case but the flood is fed of single phase board 25mm tails of mains henlys, roller do0r on a 3 phase board on 60a main fuse other end of yard

 

[Knobhead]

Can you get some photo's or do a drawing of this set up?

You're not going to get a good answer by feeding us dribs and drabs of information.