Some fluorescent bulbs brighter than others.

[mike1234]

I'm wiring up 10x GE F40BL and some bulbs are brighter than the others. I have narrowed it down to the bulbs them-self and not the wiring or the fixtures because when i swap the bulbs into a different fixture, they are still brighter than the others. I'm assuming since the bulbs are brighter, that they are emitting more uv rays than the dimmer ones but i'm not sure about it. Anyone dealt with this before? Any info is insight is greatly appreciated.

 

[somersetsparks]

Are the tubes all of the same make and type, there are different shades and light intensity ones available

 

[trev]

WTH is going on with that extension lead behind your tubes mate? Surely it wasn't bought like that?

 

[DurhamSparky]

just depends on the chemical reaction.... some better than others....

 

[mike1234]

all of the bulbs are GE T12 f40BL. That was one of the first things i checked. The extension lead is something i did up this morning. These will be going into a box for an exposure unit.

 

[trev]

Mike, get rid of that monstrosity. The use of extension leads in general should be avoided as much as possible but that one, Crikey!

 

[somersetsparks]

As durham says, you always get the odd one that is brighter then others, I assumed it was probably the fittings, you only really notice it if you have a whole row of them though, or 10 next to each other it would seem,
Best bet if your worried is to buy another batch and see if you can 10 with the same intensity

 

[mike1234]

Why's that?

 

[DurhamSparky]

i predict a fire!!!

 

[mike1234]

I talked to some other guys who built diy exposure units and they wired theirs the same way without any problems so whats the big deal here? The cord is rated at 13a so im not even close to overloading it.

 

[trev]

I'll start at the plug top end shall I?
What rating is the fuse/bit of silver paper?
What cross sectional area is the flex coming from it to that junction box?
What cross sectional area cables are connected to the junction box?
How many other extensions are connected/plugged in to that one?
What is the total wattage of all appliances connected to that extension lead?
Are you aware that a DIY lead like that will possibly invalidate your insurances if it is found after the fire which Durhamsparky quite rightly predicts?
How many more of these are dotted around your installation?
That's just a few off the top of my head Mike and I'm sorry if it sounds like I'm having a go at you because that is not my intention

- - - Updated - - -

If I'm wrong I'll apologise in advance

 

[mike1234]

To clear up any confusion, the fixtures are all on the same cord rated at 13amps(1625watts) which is plugged into a power strip for the use of the switch.

 

[Submains]

Must learn to read op properly.

 

[Richard Burns]

It looks like you have two types of GE lamp there the blacklight and the blacklight blue.
They are the same designation but the blue ones have a visible light blocking coating that removes some of the visible light at the lower end of the spectrum so they look bluer.
There is a greater UV intensity for the blacklight vs the blacklight blue.

 

[mike1234]

The designation for black light blue would be f40blb these are all f40bl ....