Dimmable CMH ballast : can I use it safely?

[Azeotrope]

The main criteria in operating at a reduced wattage or "dimmed" is that the bulb should be brought to full wattage/output for at least 10 minutes prior to dimming. Not that I would know as I am a measly engineer that admittedly hates the way the "grow light" vendors tend to give very shady advice regarding CMH/CDM bulbs/ballasts.

 

[gh0stm0de]

The main criteria in operating at a reduced wattage or "dimmed" is that the bulb should be brought to full wattage/output for at least 10 minutes prior to dimming. Not that I would know as I am a measly engineer that admittedly hates the way the "grow light" vendors tend to give very shady advice regarding CMH/CDM bulbs/ballasts.

What part of what I said was shady in any manner? You are talking about a different point than he was. He was not talking about letting the lamp operate for 10 minutes prior to dimming as you mentioned. Furthermore, my comment did not relate to allowing a lamp to operate for 10 minutes prior to use.

Instead, he mentioned that the lamp must be turned off for wattage changes and that it was unsafe to dim or boost lamps during operation. This is not the case.

So which part was shady?

 

[FrozenFire]

I was going to leave a long ass post that went into great detail. Instead I'll tell ya I have ran the 630w bulbs at less that 630w with no issues. My bloom tent bulbs stay at 700w and get run for a year before I change them out. They get rotated from bloom tent to veg tent. No real noticable lack of output after a year of 12 hour days at 700w. I dont do any break in period or shut off to dim. I just hit the dim setting while it's on. No bulb failures with 630w bulbs in over 2 years.

Azeotrope: why did God make welders?
Because engineers needed heroes too!

Jokes aside here is some candyland that just finished drying, grown under 4200k 700w de cmh.

 

[rastafari80]

don't meant to be offensive but I always trust a manifacturer better than a vendor with a badge on a forum.
plus, for a 100$ bulb I prefer to be safe than sorry.

 

[FrozenFire]

I dont trust manufacturers or salesmen. Both are in business to separate you from your money. My favorite thing manufacturers put out are the spectrum charts that fan boys use to chest thump about my thing is better than your thing with. Fyi 100 per bulb is rather cheap with regard to service life, output, and efficiency. Not so long ago it was single end hps/mh bulbs which were less efficient, put out more heat, have shorter service life, and cost about the same depending on brand.

 

[rastafari80]

anyway I didn't want to be rude, my motto is "safer is better".


@frozenfire: well, that's another big problem: you can't really compare spectrum charts of the manufacturers... that's crazy.