ESV
+ Reply to Thread
Results 1 to 9 of 9

Thread: Grounding a 70w MH ballast

  1. #1
    Senior Toad Licker naturebatslast's Avatar
    Join Date
    Jan 2006
    Location
    43°39'56" -70°15'17"
    Posts
    3,060

    Default Grounding a 70w MH ballast

    Wiring a 70w Ballastwise 70w MH ballast I'm confused on how to ground it, especially since I shocked myself twice.
    The ballast says it must be grounded, but there's no wire for it. Would I wire the ground from the lamp to the plug, and bypass the ballast?

  2. #2
    Moody and emotional slob Jennifer's Avatar
    Join Date
    May 2007
    Location
    Salem, MA
    Posts
    1,906

    Default

    From looking at the information provided by your link. It appears that just the ballast case needs to be grounded to the house outlet. (green wire)

    Hope this helps.

  3. #3
    Senior Toad Licker naturebatslast's Avatar
    Join Date
    Jan 2006
    Location
    43°39'56" -70°15'17"
    Posts
    3,060

    Default

    Hmm, so wiring the green from the plug to the ballast case?

  4. #4
    Moody and emotional slob Jennifer's Avatar
    Join Date
    May 2007
    Location
    Salem, MA
    Posts
    1,906

    Default

    Si Senor

    Also it is common but not totally necesary to ground the MH socket holder(nothing connected to the socket just the metal bracket that supports the socket) and reflector.

    Just continue that green wire up from the ballast case to the reflector/holder.

  5. #5
    Senior Toad Licker naturebatslast's Avatar
    Join Date
    Jan 2006
    Location
    43°39'56" -70°15'17"
    Posts
    3,060

    Default

    That worked, thanks!

  6. #6
    Senior Member emabie's Avatar
    Join Date
    Mar 2006
    Location
    Leominster, MA
    Posts
    609

    Default

    Quote Originally Posted by Jennifer View Post
    Si Senor

    Also it is common but not totally necesary to ground the MH socket holder(nothing connected to the socket just the metal bracket that supports the socket) and reflector.

    Just continue that green wire up from the ballast case to the reflector/holder.

    This would be important if you want the GFI to trip if the light were to fall into the tank. (hopefully you are using a GFI)
    180g Disp, 50g Sump w/ MRC II Skimmer
    55g refugium, 300g low light sump = 500g Water
    Return: Reeflow Hammerhead
    (3) 250w Mh (4) T5 actinics
    AC2

  7. #7
    Moody and emotional slob Jennifer's Avatar
    Join Date
    May 2007
    Location
    Salem, MA
    Posts
    1,906

    Default

    You are welcome, Glad it worked out for ya!


    Quote Originally Posted by emabie View Post
    This would be important if you want the GFI to trip if the light were to fall into the tank. (hopefully you are using a GFI)

    Just curious and please dont take this the wrong way.
    Are you an electrician or someone with an electronics background?
    Last edited by Jennifer; 11-10-2009 at 02:02 PM.

  8. #8
    Senior Member emabie's Avatar
    Join Date
    Mar 2006
    Location
    Leominster, MA
    Posts
    609

    Default

    Quote Originally Posted by Jennifer View Post
    You are welcome, Glad it worked out for ya!





    Just curious and please dont take this the wrong way.
    Are you an electrician or someone with an electronics background?

    I guess I should have been more detailed here:

    The GFIC monitors the current that travels through the circuit on the hot and neutral sides. If it senses more current going out than back in (a ground fault) it trips. This would protect you from shock if the light went into the tank and you put your hand in to grab it (thus creating a ground fault via your body). The current traveling through your body to ground would cause the GFIC to trip before you were badly shocked. You may feel a slight tingle but not enough to do damage.

    However, It would not protect from the current overload of dropping the fixture into salt water. Saltwater is highly conductive. If the light were to fall into the tank with no ground wire then the fixture would short out and draw allot more current than usual. This current would not trip the GFI as it would be going out the same circuit it was traveling back down (no ground fault), this extra current draw could cause the wiring to overheat and a possoble fire in the hood, stand ect. Your circuit breaker would trip once the current exceeded whatever the breaker size was. 15 amps is typical and allot more than most light fixture wiring is designed for.

    If there were a ground wire on the fixture than the current would flow down the ground causing a difference between what was going out the hot and coming back down the neutral. This would trip the GFIC.

    If you had an in tank tank ground probe it would also cause a ground fault and open the GFIC.

    Yes, I do have a strong electrical background.

    The light would function fine with no ground wire to the socket. I just tend to error on the side of caution when it comes to electricity, saltwater and people's safety.

    After all, if you are in the hospital or worse who is gona do your water changes

    Hope this clears up any questions.
    180g Disp, 50g Sump w/ MRC II Skimmer
    55g refugium, 300g low light sump = 500g Water
    Return: Reeflow Hammerhead
    (3) 250w Mh (4) T5 actinics
    AC2

  9. #9
    Moody and emotional slob Jennifer's Avatar
    Join Date
    May 2007
    Location
    Salem, MA
    Posts
    1,906

    Default

    Sweet ... Good to know you have experience in these things.

    I always prefer to have my equipment grounded, and make danr shore that it is. One shock from my tank was more than I needed.

    My understanding of GFCI's was that they would trip if there was a short between Hot (black) and neutral (white ) as well as between The HOT and the ground (green).

    Thanks for not taking it personal, as it was not intended that way.

+ Reply to Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
masna.org