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about lights and ballasts

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    HELP! about lights and ballasts

    I have a 400w light set up I bought very cheap and it works great with the new MH bulb I bought but my new 400w hps light wont work in it. Are there different ballasts for each?

    Hey philly2van, are you sure the bulbs not bad?
    Most ballast are switchable or auto switch, make and model? google it my help to find out.
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      A less common problem is failure of the ignitor. Metal halide lamps do not require an ignitor to start, so the test for a failed ignitor for an HPS lamp is to screw in a metal halide bulb of the same wattage and see if it starts. If the MH lamp starts and a new HPS lamp does not start, the ignitor probably needs to be replaced.


      • DrPhoton
        DrPhoton commented
        Editing a comment
        This is possible, just rule out the bulb and this would be quite probable.

      The ballast should work for EITHER a MH or a HPS bulb so long as both bulbs are 400w and the ballast is also a 400w ballast. There are not different ballasts for different bulbs. I think Mr.furley is on to something regarding the bulb possibly being bad. Do you notice anything broken in the bulb's filament? Anything disconnected or not soldered inside the bulb?

      You could also check and make sure there are no loose wires on the bulb socket but it sounds like the issue may be in the bulb as stated before. But to answer your initial question, no...the ballast should work for either type of bulb so long as the watts match.
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        Ok this is a noob statement so bare with me..
        I had the same issue when I first moved to these higher wattage lights.. much more difficult then the natural thing huh..
        so in the beginning I bought two ballast and two hoods and a bunch other stuff I ended up not needing

        ended up with four light bulbs and it was a hassle couldn't get any of the brand new lights to work..

        then I was told two things..
        check the position of the light...
        on some bulbs there is a position indicator generally just a little piece of metal sticking out sometimes it locks in sometimes it doesn't

        second was.. and here's the one I still don't understand..
        dont touch the light with your hands and if you do wipe it off
        this person told me that the oils in your hands can effect the light..
        done those two things and miracliously all four lights work

        also read the bulb itself not the package sometimes they are mis boxed..
        I ordered two 400w mh got two 600W hps
        good thing cus I needed them lol ended up getting them free cus they were the wrong bulbs lol 😂
        But a 600w won't work in a 400w ballast (not enough juice to fire it up)
        Last edited by Daskahn; 08-12-2017, 03:27 AM.


        • DrPhoton
          DrPhoton commented
          Editing a comment
          Handling of the bulbs and the oils causing problems is a old wifes tale. Although it has bearing, its only with lights that are not insulated with a protective jacket and have the arc exposed. Like double ended bulbs.

          Sometimes if the mogul connection is not wound all the way, the base contact may not interact. Creating a open circuit. Other times this connector may deform or dislodge, so making sure proper contact is made rules these out.

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