WOW, HUGE lumen loss!

[Lazyman]

Hey guys, just wanted to let you know something I found the other night, still trying to get to the root of the issue.

Using a cheap footcandle meter, I measured my new Quantum digital ballasts + 1000W Eye HPS and MH bulbs in Xtrasun 6" AC hoods when I first got them, and compared them to my analog ballasts using the same hoods and bulbs. I got the following figures at 22 inches from the bulb:

HPS/digital ballasts = 6500 foot candles
MH/digital ballasts =5500 foot candles

HPS/coil ballasts = 5500 foot candles
MH/coil ballasts = 4500 foot candles.

10 weeks later I checked a couple lights with the same meter, and I shit you not, got the following readings on my digitals:

HPS/Digital ballasts = 1000 foot candles
MH/Digital ballasts = 800 foot candles

WTF? I have two brand new Hortlux bulbs that my local shop gave me after the quantums burned them out in 6 and 8 weeks, so I can test if it's the bulbs losing brightness, and I need to fire my analogs back up for comparison, but that is a CRAZY big loss.

ANyone else notice anything like that? The lights still look bright, but according to my meter they just aren't!

 

[billbob]

maybe the meter is bad???

 

[K.J]

"Using a cheap footcandle meter"

That'd be where I started.

 

[Lazyman]

Yeah I thought about that too, but for it to randomly go bad after years of use? Seems kinda unlikely. ANybody got a digital ballast and a light meter that can take a peek tonight when their lights are on? I may grab another meter to be sure, but it just seemed too odd not to mention.

 

[blynx]

I had a 600hps 120v digital lumatek ballast that did the same thing with hortilux bulbs. They started out kinda bright and I thought they were getting dimmer over time. I pulled out my light meter and got real low readings like you, almost CFL levels haha. Then about 2 weeks later the bulb died.

I got a new cheap bulb and it was super bright and worked great until the ballast died 2 mos later.

 

[K.J]

Yeah I thought about that too, but for it to randomly go bad after years of use? Seems kinda unlikely. ANybody got a digital ballast and a light meter that can take a peek tonight when their lights are on? I may grab another meter to be sure, but it just seemed too odd not to mention.

If you've been using it for years, and it's cheaply made, I wouldn't say it's just a random incident. I'd start there, just my opinion.

 

[Lazyman]

Gotcha KJ, gonna pick up another on my way to lunch and will report back tonight. This is a mystery that shall not go unsolved!

 

[Lazyman]

I had a 600hps 120v digital lumatek ballast that did the same thing with hortilux bulbs. They started out kinda bright and I thought they were getting dimmer over time. I pulled out my light meter and got real low readings like you, almost CFL levels haha. Then about 2 weeks later the bulb died.

I got a new cheap bulb and it was super bright and worked great until the ballast died 2 mos later.

Aha, the plot thickens! Thanks blynx, it's possible I'm not crazy after all! Mucho measuring to be done tonight...

 

[etinarcadiaego]

Did you try to measure your analogs with the meter again? That could tell if the meter is faulty . . .

 

[Lazyman]

Aha, mystery solved! I took the meter outside to get a baseline sunlight measurement, and still got 1500 footcandles! I peeled the case on my meter apart and the little sensor had slipped and was hidden by the casing, I stuck it back in place and BLAM, 6800 foot candles outside.

Sorry for wasting your time guys, my apologies!

I'll go for a new minutes as penance.

Still gonna take some more measurements tonight, would be good to know how the bulbs have held up for the last run. More later!

 

[resin_lung]

hahaha honest mistake. I'm curious to know how they'll read. please post results homie. Thanks

 

[Hydro-Soil]

Anyone ever come up with a cheap, yet reliable, PAR meter? Anything better than measuring lumens would be great since PAR quality drops long before lumens do.

Remember to change your lamps on a schedule and not according to your lumen meter.

 

[*mistress*]

measuring sunlight at earth's surface:build your own pyranometer

measuring sunlight at earth's surface:build your own pyranometer

Anyone ever come up with a cheap, yet reliable, PAR meter? Anything better than measuring lumens would be great since PAR quality drops long before lumens do.

Remember to change your lamps on a schedule and not according to your lumen meter.

https://www.icmag.com/ic/showpost.php?p=2469835&postcount=7:

to specifically answer your question:

quantum meter
measures the number of electromagnetic energy units (photons) available on the leaf surface in units of microeinsteins per square meter per second (ue/m^2/s).

radio meter
measures the amount of radiant energy available on the leaf surface in units of watts per square meter (w/m^2).

pyranometer
measures par (photosynthetically active radiation) watts/m^2.

measuring sunlight at earth's surface:build your own pyranometer:
http://www.pages.drexel.edu/~brooksdr/DRB_web_page/construction/pyranometer/pyranometer.htm

see also:
https://www.icmag.com/ic/showthread.php?t=127379&highlight=quantum+meter
This is a gold mine of cannabis growing laboratory research

hope this helps. enjoy your garden!

 

[DiscoBiscuit]

I'll go for a new minutes as penance.

LOL. Nah, that'll be the first thing I check if my meter goes bad. Thanks for the info. I'd rep ya but have been checked by the rep police for the day.

 

[Lazyman]

Ok, just to update anyone still hanging out, I have the measurements taken with the repaired meter, again 22" from the bulbs:

Digital (Quantum 1000W 240V ballasts:

MH 5300 footcandles (lost 200 footcandles in 10 weeks)
HPS 5800 foot candles (lost 700 foot candles)

Analog/Coil ballasts:

MH 4200 footcandles (lost 300 footcandles)
HPS 5300 foot candles (lost 200 foot candles)

So the digitals are still brighter after 2 and a half months, but the bulbs probably won't last as long as they do in the coil ballasts. I'll replace em after the next round is up anyway.

Thanks again guys...

 

[resin_lung]

Thanks for the update lazy. I think that seems to be normal. brighter but, prone to premature wear. thanks for the update.

 

[Lazyman]

No prob bro, hahaha! look at that purple leaf! You maniac you...

 

[Greyskull]

so how do you like the quantums?
what kind of core & coil are you rocking?

 

[Lazyman]

So far I dig the quantums bro, my local shop told me they get 1 quantum back for every ten lumateks, no problems so far. They run cool and their little fan does work well, I just worry about when the fan will fail. The dimmer switch is neat, I imagine all digis will have the 10% extra lumens setting like the new Lumateks soon enough...

My old ballasts are Sunsystems, cant even remember the model (they're about 5-6 years old now, bought em new.) Reliable workhorses though, never had to touch em.

 

[bushdoctor215]

Ok, just to update anyone still hanging out, I have the measurements taken with the repaired meter, again 22" from the bulbs:

Digital (Quantum 1000W 240V ballasts:

MH 5300 footcandles (lost 200 footcandles in 10 weeks)
HPS 5800 foot candles (lost 700 foot candles)

Analog/Coil ballasts:

MH 4200 footcandles (lost 300 footcandles)
HPS 5300 foot candles (lost 200 foot candles)

So the digitals are still brighter after 2 and a half months, but the bulbs probably won't last as long as they do in the coil ballasts. I'll replace em after the next round is up anyway.

Thanks again guys...

Holy crap! That`s a 20% difference on the MH. I`m gonna buy one of these digitals and give it a test. Who cares if the bulbs burn out quicker. That`s like running 5k and only paying for 4k. IDK exactly how you did your test but to be fair, the exact bulb and hood sould be used. This means disconnecting the wires at the socket and re-connecting the cords(I don`t think the plugs are the same). A brand new ballast should be used for both and 30 mins warm up. I understand your test wasn`t digi vs coil. Thanks for doing the lumens test and sparking some interest.