Results 1 to 5 of 5

Thread: Dimmable Ballast question...

  1. #1

    Join Date
    Aug 2021
    Posts
    2,498
    Thanks
    11,180
    Been Thanked: 15,808 Times

    Default Dimmable Ballast question...

    If you have a dimmable ballast, must you replace the bulb (wattage) its rated for before you use the dimmer? I.e., If you have a 400 watt hps bulb and wished to dim it to 250 watts, must you use a 250 watt bulb?

  2. The Following 3 Users Say Thank You to mpsj For This Useful Post:

    Farmer Geddon (02-11-21), GEORGE (01-11-21), Mac (02-11-21)

  3. #2

    Join Date
    May 2014
    Location
    Asgard
    Posts
    7,100
    Thanks
    10,346
    Been Thanked: 26,716 Times

    Default

    Nah, you can get lamps that can be dimmed. I used to use a 600w metal halide and dim it to 250w.

    Sent from my SM-G981B using Tapatalk

    "A word to the wise isn't necessary -- it's the stupid ones that need the advice."

  4. The Following 5 Users Say Thank You to Loki For This Useful Post:

    Farmer Geddon (02-11-21), GEORGE (01-11-21), Mac (02-11-21), mpsj (01-11-21), twalte (01-11-21)

  5. #3

    Join Date
    Aug 2021
    Posts
    2,498
    Thanks
    11,180
    Been Thanked: 15,808 Times

    Default

    Quote Originally Posted by Loki View Post
    Nah, you can get lamps that can be dimmed. I used to use a 600w metal halide and dim it to 250w.

    Sent from my SM-G981B using Tapatalk
    When you dimm from 600 to 250 do you notice a significant brightness change?

  6. The Following 4 Users Say Thank You to mpsj For This Useful Post:

    Farmer Geddon (02-11-21), GEORGE (01-11-21), Loki (01-11-21), Mac (02-11-21)

  7. #4

    Join Date
    May 2014
    Location
    Asgard
    Posts
    7,100
    Thanks
    10,346
    Been Thanked: 26,716 Times

    Default

    Quote Originally Posted by mpsj View Post
    When you dimm from 600 to 250 do you notice a significant brightness change?
    I made a small mistake, I used a duel spec lamp, not a metal halide. But yeah, you do notice the difference in brightness, plus the spectrum looked slightly more yellow than the normal orange of a duel spec lamp

    Sent from my SM-G981B using Tapatalk

  8. The Following 4 Users Say Thank You to Loki For This Useful Post:

    Farmer Geddon (02-11-21), GEORGE (01-11-21), Mac (02-11-21), mpsj (02-11-21)

  9. #5

    Join Date
    Mar 2009
    Posts
    62,168
    Thanks
    177,534
    Been Thanked: 196,771 Times

    Default

    Bulb manufacturers seem happy for a 600w bulb to be dimmed to 400w... but they reckon to dim to 250w, either use a 400w or 250w bulb. They don't say why but I epect spectrum shift (as Loki says above)
    It's Not What You Know, It's What You Can Prove

  10. The Following 5 Users Say Thank You to M_C For This Useful Post:

    Farmer Geddon (02-11-21), GEORGE (02-11-21), Loki (02-11-21), Mac (02-11-21), mpsj (02-11-21)

Tags for this Thread

Bookmarks

Posting Permissions

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


THCtalk.com Disclaimer - You must be over 18 years old to view/use this site .THCtalk.com does not encourage growing Cannabis or possessing Cannabis. Learning how to grow Cannabis instructions should be for educational purposes only. All Information contained in this web site is for: Historical reference, Scientific reference and Educational purposes only. Visitors to this website are advised against breaking the law as It is illegal to smoke, grow, or possess cannabis in the UK and some US States