PAR36 ACL, which bulb?

[Davyx]

Hi,

 

I got a set of PAR36 ACL bars. Most of the bulbs are dead and must be replaced.

 

Is there a big difference in the beam between 100W and 250W bulbs (in 28V of course)?

 

What about the brand? Prices are going from 9€ to 20€ or more for a 250W/28V bulb. Is this difference of price justified between a GE, Omnilux or Osram bulb?

 

With your experience, which model could you suggest? I'm planning to use them in medium size rooms.

[niclights]

I've always used 250W. I think you'd struggle with 100's. I wouldn't worry too much about brand - they're a very simple lamp.

[tlc]

You must of course not mix 100w and 250w in a single series set.

 

(mixed and they will not see "28v" on each lamp , need to be the same resistance to do this)

 

All must be 100 or all must be 250.

 

You can have 2 strings of 250w (on strong colours say) and 1 string of 100w

(on white they will compare to the strong gelled 250w)

 

but inevitably mixing 2 types is a bad idea , eventually someone will use the wrong replacement and cause quick fail of a lamp.

[Davyx]

You must of course not mix 100w and 250w in a single series set.

 

(mixed and they will not see "28v" on each lamp , need to be the same resistance to do this)

 

All must be 100 or all must be 250.

 

You can have 2 strings of 250w (on strong colours say) and 1 string of 100w

(on white they will compare to the strong gelled 250w)

 

but inevitably mixing 2 types is a bad idea , eventually someone will use the wrong replacement and cause quick fail of a lamp.

 

I didn't mean to mix both power, I was just wondering if there was a big difference between 100W and 250W as well as in the different brands.

[adam2]

As others post, it is vital that all lamps in a series string be of the same wattage*, what is not allways appreciated is that even very small differences in wattage will be unsatisfactory in series.

 

I would therefore suggest that whichever brand of lamp you chose, that they should all be of the same brand.

If lamps of different brands are burnt in series, there is a risk that they may differ slightly in actual wattage, and the life of some lamps be much reduced as a result.

 

For example if the actuall wattage of brand "A" is 245 watts, and the actuall wattage of brand "B" is 255 watts, then the voltage accross the brand "A" lamps will be enough to reduce the life substantialy.

If all lamps are the same make, they are more likely to be eqaull in actuall wattage.

 

*to be strictly accurate, the current of all lamps should be equall, in theory you could run 28 volt, 250 watt lamps in series with 56 volt, 500 watt lamps, in practice though this is seldom done.