halide lamp ballasts

[ollski]

Continuing the saga of the problem with my 400w twin halide unit. For some reason since I introduced new 10k lamps they (one a lot more than the other) kept going out and trying to reignite immediatly. Originally this happened once or twice a day but after a few months was going 20 times a day. I presume this killed the ignitor unit so I bought a new one today (nothing like existing and cant see how to wire it but....). When I opened the ballast unit I found this on top of the analogue clock unit:

Anyone know what it is, why it's wired in and if I can replace it?. Also wondering if it could have caused the problem with the lamps or the other way round?

 

[ColJack]

2 possibilities..

thermal cut out

or some sort of surge protection..

number on it looks like sg40.. tried a google search? or possibly a RS search?

EDIT: and the surge protection has it...

http://www.rhopointcomponents.com/products.asp?recnumber=10

 

[ollski]

Many thanks, presume this was caused by the unit attempting to relight the lamp before it cooled.

 

[ColJack]

could be the cause of the re-lites.. break causing intermittent connection when getting hot..

getting worse over time as the heat causes either softening of the legs and reduced spring force holding the break together, or erosion of the contact points where the break meets..

i'd also be weary of that brown cable that goes under where the screw goes.. might wanna move it out of the way a bit just in case..