how many amps?

[Bayou]

Anyone have a link to somewhere that I can figure out how many amps my 250W MH ballasts are pulling?
I had found the info last year, but I lost it!

Thanks

 

[chrisk]

Not to be annoying, but isn't it printed on the ballasts?

 

[melev]

This is just a general amount using loose math, but basically 250w is 2.5 amps.

 

[Bayou]

I'm planning right now and do not have the ballast in my hand.

And yes that was a little annoying. :wink:

 

[chrissreef]

I thought you take the watts /120v sockets?

250/120=amps

+ ballasts use some electricity so I's say add in 50w more for electric ballast and 80 more for magnetic?

 

[Wes]

who makes it?

 

[chrisk]

:-D

Different ballast have different efficiencies (especially between magnetic and electronic) and therefore would have different amp draws.

I think you can also use a kill-a-watt meter if you actually have the ballast in hand and setup.

 

[Ashlar]

And to make matters even worse, there may be a 'peak' draw on startup that is even higher.

 

[Firewolf4]

I generally plan as rule of thumb that 250W MH's draw about 3.5 amps and have an inrush of around 9 for about 1/2 a second. It's good for guestimating power consumptions. I imagine I'll throw a clamp on ammeter one of these days and sample it with my scope.