HPS Light w/o Ballast?

I have an HPS Light that I bought used. It blazes something fierce when I turn it on (after about 5min of warmup), but it's just got a standard plug for a wall outlet. Now, I understand that the ballast is used to control the flow of electricity to the bulb. If my light is working fine without an external ballast (one of those heavy boxy things that I see with most HPS lights), does that mean it probably has one built-in?

Is it safe to run this light for months on end without an external ballast?

I'm not right by the light, so I can't tell you the brand/model. I know it works, and it's bright even just plugged into the wall. Is that good enough?

hi to you aardvarki, post sum pics of it can you?

It would have to have an igniter to fire, that kind of seems to me that it has an internal ballast of some sort in it...Post Pics!!

I don't have a camera, so unfortunately can't post pics. It looks like a pretty standard HPS, but it's got a standard wall-outlet plug rather than just bare wires or the weird plugs that go into some ballasts. I've had it running for a few hours with no noticeable negative affects. It's not starting fires, it's only heated the room to 23C (25-28C between the light and the plant), and it's still shining bright.

Your sure its hps as hps will need a ballst for th igniter and I have never heard of an internal igniter built into a bulb.Any web site that shows it???

Is it a floodlight type or like a growlight. Is it just reflector, socket and cord or is it all enclosed in casing. If that makes sense. Google hps lights and find a pic that looks like yours. Im using a floodlight 150watt.

is the bulb like this?SON-E 400W Internal ignitor - Lightbulbs Direct - Your source for buying domestic light bulbs!

I just found this quote next to an image that looks just like my light:

"These Grow Lights are just the right size for a small indoor garden-- The ballast is housed inside of the hanging reflector, which makes this system perfect for hanging from low ceilings or under a shelf."

Grow lighting and hydroponics supply from HydroFarm

Under the "Sunburst Grow Light" section.