# Mercury Vapour Bulbs



## Grond (Jun 17, 2008)

Does anyone have any experience with self ballasting mercury vapour bulbs? I've just bought one and had it running for a few days (with a view to potentially moving away from fluorescent tubes). 

My problem is that the bulb keeps going off for a minute or two and then it comes back on spontaneously! There is no problem with the electricity supply as the power light for the light fixture its attached to doesn't waver or go off.

I just want to know whether this is normal, or if i've been sold a duff bulb and need to send it back (they're not cheap and I don't want a dodgy one!). I am using the exoterra variety.

Thanks


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## trunx (Sep 29, 2008)

ive used them for over a year. never had this problem at all. i know when you turn them off you cant turn them on again till they cool down- 10ish minutes. maybe a duff bulb or timer maybe?...........


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## Grond (Jun 17, 2008)

Could be the timer I suppose. Will try it without the timer and see what happens!


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## Athravan (Dec 28, 2006)

It is normal with some MVB bulbs, specifically certain makes. If you phone the manufacturer they should tell you that this may continue for a few days and should sort itself out. If it doesn't sort itself out after a few days the manufacturer should replace the bulb for you.


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## mEOw (Dec 28, 2006)

some of them do this sometimes, never quite figured out why but people usually have one of two answers... 1, send it back, its broken and 2, they sometimes do this for the first few days, they have a thermal cutout inside the bulb and some of them run hotter than usuall for the first few days... 
2nd answer seems fishy to me but when i got a bulb that was doing this i told the people at mega ray and they sent me a replacement out. still have the dodgy bulb sat in the cupboard as an emergency spare though, if they fix themselves i might give it a try again sometime..lol


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## mEOw (Dec 28, 2006)

forgot to mention, out of the 20 or so mvb's ive bought, all sorts of diffrent makes, only one bulb ever did this. have had 6 mega rays that dont, and one that does and was replaced. (hence why i dont really believe they are meant to)
Owen


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## Rencey (Sep 5, 2008)

what is the best mvb i ask this as been reading up on them and i keep swaying from one to the other. the power sun throws its uva/uvb upto 6ft the mega ray doesn't fade as bad but has a distance of 20" and then you have the sunglo (cheap) and the t rex one.
would i be right in sticking with the power sun:whistling2:


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## mEOw (Dec 28, 2006)

i stuck with mega rays, powersuns i had all blew within 6 months of buying them. saying that i have heard a lot of very good things about the new sunglo bulbs, and have 2 here that im pleased with at the moment (only had em a month or so though so cant say how good they are in the long term yet) 
Owen


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## Athravan (Dec 28, 2006)

I'm using the Exo Terra Sun Glo at the moment too but like Owen says they are pretty new on the market - I would really love to see some studies on deteroriation and UV output before making my mind up for sure, but so far so good.


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## zune_lai (Feb 6, 2008)

Ive read that some mvb go off for a while if it overheats


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## mEOw (Dec 28, 2006)

Athravan said:


> I'm using the Exo Terra Sun Glo at the moment too but like Owen says they are pretty new on the market - I would really love to see some studies on deteroriation and UV output before making my mind up for sure, but so far so good.


just realised the exo terra oens are solarglo not sunglo.. but still

there are already uv readings posted around the place, but nothing long term yet as they are too new... personally i got initial readings of 197uW/cm2 and 193uw/cm2, and then after 2 weeks i got 172uW/cm2 and 169uW/cm2... seems reasonable for the first 2 weeks of burn in, i expect the decay has slowed down a lot since (hopefully) will have to check them again soon though and see what their output is like..


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## Rencey (Sep 5, 2008)

Rencey said:


> what is the best mvb i ask this as been reading up on them and i keep swaying from one to the other. the power sun throws its uva/uvb upto 6ft the mega ray doesn't fade as bad but has a distance of 20" and then you have the sunglo (cheap) and the t rex one.
> would i be right in sticking with the power sun:whistling2:


 
my mistake its the solar glow thats the mvb the sun glow is the normal basking spot :whistling2:


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## Rencey (Sep 5, 2008)

mEOw said:


> just realised the exo terra oens are solarglo not sunglo.. but still
> 
> there are already uv readings posted around the place, but nothing long term yet as they are too new... personally i got initial readings of 197uW/cm2 and 193uw/cm2, and then after 2 weeks i got 172uW/cm2 and 169uW/cm2... seems reasonable for the first 2 weeks of burn in, i expect the decay has slowed down a lot since (hopefully) will have to check them again soon though and see what their output is like..


 
i got to get a mvb monday to do my week of testing in my new viv so off the top of your heads peeps what one (price no issue as would not put achillies at risk for the sake of £20 - £30)


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## trunx (Sep 29, 2008)

im using a powersun and am happy with it. never used the others, so they could be better. who knows eh...............


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## Graham (Jan 27, 2007)

In independent tests the MegaRay/T-Rex (same bulb under different brand names) consistently comes out tops on all counts, reliability, lifespan, output levels. 

The flickering in new bulbs is apparently something to do with a mis-match with European mains supplies, the new production bulbs for the European market are being changed from 100W to 110W which is supposed to cure the problem.

Shutting off can also be caused by overheating so it's important to use suitable holders, if the shade is too small then air cannot circulate around the bulb causing it to overheat.


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## Grond (Jun 17, 2008)

The bulb in question _is _solarglo from exo terra. All the exo terra stuff i've used in the past has been ok so i thought i'd experiment with a cheaper model!

It's not enclosed it's in a wire frame ceramic holder so it shouldn't be overheating.

The electricity supply thing sounds strange. The bulb i'm using is 125w.

Will leave it for a few days and see if it settles down! If not I can feel a letter to exo-terra coming on!

Thanks for the discussion and advice guys.


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## Rencey (Sep 5, 2008)

Grond said:


> The bulb in question _is _solarglo from exo terra. All the exo terra stuff i've used in the past has been ok so i thought i'd experiment with a cheaper model!
> 
> It's not enclosed it's in a wire frame ceramic holder so it shouldn't be overheating.
> 
> ...


i am assuming its exteranally ballast then.
the humming will be the emf. the ballast is moving 50 times a second (when i say moving you wont see it with the naked eye). kinda along the same lines as a transformer, electricity passing between two coils @ 50hz.:whistling2:


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## Tina (Apr 9, 2007)

I'm having the same problems with the megaray 100w... randomly turns itself on and off all day long. 

I spoke to the supplier who, as Graham has already said, confirmed they're changing to 110w as there's a problem with the filament for the European market. 

I was told it might settle down, but it hasn't so I'll be sending it back for a replacement.


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## Grond (Jun 17, 2008)

Still at it! Getting more frequent if anything. Will contact supplier on Monday!


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## kaimarion (Dec 31, 2007)

Not to try Hijack a thread but can anyone tell me where to get an MVB and which is the best to get.





Thanks  .


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## SWsarah (Aug 6, 2005)

Kimbos sell the mega ray www.kimbosreptileworld.co.uk

I sell powersun and the solarglow www.shelledwarriorsshop.co.uk


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## kaimarion (Dec 31, 2007)

blondesarah said:


> Kimbos sell the mega ray www.kimbosreptileworld.co.uk
> 
> I sell powersun and the solarglow www.shelledwarriorsshop.co.uk


Thanks  .


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## Dogmatix (Nov 12, 2008)

Sorry to bring up an old relic... but has anyone done studies on the SolarGlo bulbs now? 
I've been doing some reaserch and found them to be cheaper than compacts and standard UVB tubes, and want the best I can afford.


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