Hi everyone, I am working on setting up my new Robertson brand M98 ballast to run a 70 watt Sylvania metal halide lamp.  Below, I have the ballast and ignitor pictured, along with a diagram on the side of the ballast of what goes where. 

In the first picture, I have the brown extension cord on the bottom left representing the power cord.  The black and yellow striped wire and the white wire are hypothetically attached to the power cord.  I have the red wire and the white wire running from the black ignitor to the lamp fixture (light bulb in my picture.) Please let me know if I'm on the right track.  Your help is greatly appreciated! 

Very close.

-Both the red from the ignitor and the ballast go to the center pin of the lamp
-The white of the ignitor and screw of the lamp are also neutral and should be connected as such. there may be two white wires from the ballast. both will be neutral. you can use one for connecting to mains and the cap, the other for the lamp and ignitor

Very close.

-Both the red from the ignitor and the ballast go to the center pin of the lamp
-The white of the ignitor and screw of the lamp are also neutral and should be connected as such. there may be two white wires from the ballast. both will be neutral. you can use one for connecting to mains and the cap, the other for the lamp and ignitor

Thank you 589! 

No problem, I annotated a shot of the ballast you provided to help you see how I arrived at that observation. The green circles are wire nuts and the arrows are bare ends.

No problem, I annotated a shot of the ballast you provided to help you see how I arrived at that observation. The green circles are wire nuts and the arrows are bare ends.

Thank you for your picture here  My first project like this with my HPS lamp ballast was quite a bit of trial and error, but this diagram will make this second ballast much easier.  I just need to find some insulator boxes and a porcelain lamp socket and I’ll be in business! 

Is your lamp protected ? If not, you might want to consider a protective enclosure.

You will like the light output of this lamp, I'm sure !

Is your lamp protected ? If not, you might want to consider a protective enclosure.

You will like the light output of this lamp, I'm sure !

This lamp is not protected, although I plan on wearing sunglasses while it’s at full brightness and not leaving it on for more than a few minutes at a time. What’s the lumen output for an average 70 watt clear MH?

I just need to find some insulator box expansions at a different hardware store and I’ll be good to go!  Thank you everyone for your help and replies on this topic!

Sunglasses will not offer the protection required by a MH lamp explosion. Although the probability is very low, it is not non-existent. Some members here run unprotected MH lamps in the open with no problems, however I'm not one of them.

The problem with unprotected MH lamps is a risk of arc tube rupture and explosion. When that happens, obviously the arc extinguishes so UV (and sunglasses) are not a problem (or a solution). Upon arc tube explosion, there is a very high risk of outer envelope rupture as well and it can send red-hot particles of glass flying. Any combustible material onto which these land have the potential of catching on fire, and if they land on skin, they will cut and burn. I'm just stating the facts so you can make an informed decision on this matter.

While what sol is saying is correct they can rupture and drop red hot glass fragments, If it's a new lamp the odd's of a violent arc tube rupture is very small, just run it over a non-combustible surface, and if you plan on using it for unattended lighting service make sure it's got a cover over it, even something like a large mason jar will work to catch and contain arc tube fragments if it goes pop and they will fit the wide mouth versions, or keep an eye out for a protected arc tube lamp, they have a thicker glass tube inside the bulb around the arc tube so the envelope will contain the fragments these are rated of open fixtures. But if you don't run them past there rated hours the odds of this happening are still pretty small, the problem is normal people will run them till they die 24/7 which is hard on a metal halide lamp, while the people here understand the importance of when it's time to relamp and know what to look for like a large color shift in the light, if they go pink or green it's usually an indication of it's time to relamp, normal people don't, and will wait for it to die because they don't want to spend the money on something that is still working, even if the light output is reduced by about 40% and they are wasting money powering it...

 

Sounds like there are quite a few risk factors with MH lamps.  Thank you all for letting me know up front!   I'll certainly use good judgement while running this lamp.  As mentioned before, this is not going to be used in a long term application.  I'm just building this ballast and fixture "for fun" and I'm not planning on using for more than a few minutes at a time.

I have much more experience with high performance halogen lamps and I know those have a risk of exploding, too.  I'm assuming a metal halide lamp is just as pressurized as a halogen lamp, and plan on using the same precautions while running it.  While my sunglasses will protect my eyes from the UV rays, I know a halogen explosion would be powerful and destructive enough to cause burns or cuts anywhere else. 

Instead of a plain ceramic socket to put on top of the insulator boxes containing the ballast and ignitor, I might get a clear globe light that encloses the MH lamp and also allows it to be visible.  Perhaps something similar to the one below.  That would make a cool lamp

Thanks again for your advice and wish me luck!

Here’s my final product  It works perfectly!  Thank you everyone for your assistance!

Congrats! It looks good