I have a 700 watt mercury vapor bulb and needless to say, I'd like to burn it  However, I can't find a 700 watt ballast anywhere. Does anyone here have a 700 watt ballast they'd like to part with? Or a place I might find one? It should be 230 volts.

Also, I was wondering if I can't find one I might use a 600 watt plus a 100 watt ballast, would that work? Or a 400 and a 250? Suggestion are very welcome.

Thanks a big bunch. 

Best of luck, 700W ballasts for 230V are very hard to find, I've certainly never come across one, which is why I've never bought a 700W lamp

You might be able to get away with using a 1000W ballast and reducing the input voltage, but it's not recommended unless you know what you're doing. 700W lamps are rare and you don't want to blow it up 

Are we talking about 230V series choke or 120V transformers?
For the 230V you just add multiple chokes in parallel so the sum of their current matches the current this lamp need (you have to google for the required lamp arc current specs).

For the autotransformer ballasts it works the same way, but you have two extra limitation:
Both ballasts have to have their phase the same (so both lead CWA, or both lag HX)
And both ballast OCV should be close to each other.

In any case, measure the arc current after the thing is assembled and verify it matches the lamp requirements.
The usually allowed tolerance is +/-5%, if you don't mind lower light output and lower efficacy, down to -30% ("+" means current being higherthan the lamp rating, "-" lower)

thanks guys!!

@sox35 How would I go about reducing the input voltage? I have no idea so it would probably be wisest for me not to go there, but still curious

@Medved I'm talking about 230V, I live in the Netherlands so basically everything here is 230V I'm saving what you said in this post, but I understand it's not at as easy as just chuck 2 ballasts together lol I will google and look into it before even trying

thanks guys!!

@sox35 How would I go about reducing the input voltage? I have no idea so it would probably be wisest for me not to go there, but still curious

Well the way I'd do it is to use a Variac (variable auto-transformer, like this, but as I said, you need to have an idea of what you're doing before you attempt something like this. It sounds as though you're not all that experienced (no disrespect) so I'd leave well alone.

Hello Zambi71,

i bought a new ballast for 700W mv lamp in 2020.
Here is the company's address:

OPTIMA German Lighting Component GmbH

Send your request to them.


Greetings from Hamburg

Olav

A 400 watt and a 250 in parallel is the standard 700 watt set up in the UK

Well the way I'd do it is to use a Variac (variable auto-transformer, like this, but as I said, you need to have an idea of what you're doing before you attempt something like this. It sounds as though you're not all that experienced (no disrespect) so I'd leave well alone.

Thanks for replying, I think I will leave it alone

A 400 watt and a 250 in parallel is the standard 700 watt set up in the UK

Thanks!

Hello Zambi71,

i bought a new ballast for 700W mv lamp in 2020.
Here is the company's address:

OPTIMA German Lighting Component GmbH

Send your request to them.


Greetings from Hamburg

Olav

Hi Olav,
thanks so much!! I have already emailed them

Wonder if it would be easier to find a 700WMV fixture rather than just the ballast.IE a fixture that has a ballast in it.Weren't ballasts made that could run either 700W or 1000 W MV?The 700W MV is sort of odd to me never seen them until on this site.

To run on the same ballast, both lamps wpuld have to be rated for the same current.
If the 700W is 5.6A (250+400W chokes in parallel), its arc voltage is already about 140V, which is already on the top end what the 230V mains may support.
The 5.6A 1kW lamp would be then about 200V and that would need 400V feed (across 2 phases).
So to have a sinhle fixture supporting both lamps sounds to me as not much viable...

If you can get yourself over to Tienen in Belgium, you are welcome to have a 700W ballast for free.  I have a spare of the Philips BHL700 at work.  Or we could look at posting it, but that may cost more than it is worth.

One of these days James, you're definitely going to get a visit