600Watt HPS

[Uncle Chop Chop]

Hey guys I just need to know is there a way of telling when your HPS bulb is in need of replacing to get the most out of your bulb. Does it slowly burnt out out and fade or what? Hope this makes sense

 

Cheers Chops

[Ozzy420]

Over time the light out put will drop.

 

Some ppl say replace every 3 grows, but in saying that it can depend on the brand of the light, some of the cheaper ones i wont use my self.

 

I use Phillips Sun-T-Argo imo they are the best i an still using one that is for years old have lost count of how many grows it has done but still keeps kicking on, and i have found that the Sun-T has the best orange light spectrum out of all the hps lighting out there...

[m-c-hammer]

Get yourself a light meter and you can tell if has dropped significantly.

But good globes do go on and on and on. Son-T really is worth the $$

[Ozzy420]

U can pick up a light meter at dick smiths for around $50...

[GreenBeard]

I have the same question about when to replace globes.... I use Phillips SonT and I (think, can't control for everyhting everytime)I notice a difference in brightness and in the final yield between new and older globes. I don't have a light meter so can't verify the observation, although I had 3 x 600w side by side on the last grow with globes of different ages. Comparing them side by side it does seem that the new globes put out more light than older ones.

 

To have an age(hrs) v's light output graph would be nice....

[jaikai]

Hello and welcome Greenbeard... why not head into Dr Livingstone forum and say g`day mate...

 

Anyways, a rule of thumb is 4 crops or about 12mths use.

 

JAIKAI

[Pleb Scrubber]

1 year for HID bulbs... you can keep using it but it will be at a reduced lumen output...

 

Instead of buying a light meter, spend that money on a new bulb for the same cost...

[everest]

aye , well my sparky , an he all round good , bloke reckons bulbs are good till they pop.

 

i im on the fence , but not changed my bulbs .. 2 400s hps for like 3 grows now .. an still budding up the same .. ?

 

i don't nah ?

 

ev

[whazzup]

HPS lamps have light maintenance of between 85 and 96% per year (5000 hours). That's a lot of difference: lose 15 or 4 percent. For example the Philips Greenpower EL lamps have a light maintenance of more than 95% per year (5000 hours) a Son T-pia does 90% at 5000 hours. Mostly lamps need a few hundred hours to become completely stable, and some even increase in output the first few months. We had GAVITA IR lamps brought back after 2 years that had lost just 4% of their original output. It all comes down to the quality of the lamp and specifically the burner. A HID reliable supplier should be able to give you full details on survival rate and light maintenance over the first 20.000 hours. Horticultural suppliers will also be able to suplly you the light mainetnance numbers in micromoles.

 

But, if you are conscious about your lamps, are you conscious about your reflector too? I see growers change bulbs every 6 months but use 5 year old aluminum branyard reflectors. A normal reflector can lose between 3-8% reflectivity each year, just by calcium deposits (from the humid environment), burned in dirt and dust and material degradation. Specifically that last issue makes some materials not recommendable as reflector. Looks great when you begin, but after hundreds of hours being heated by a HPS lamp some materials just give up.

 

Now you would say that cleaning reflectors would be the solution. In professional horticulture we have given up on that. Yes, maybe take the dust off, but really cleaning MIRO aluminum is almost impossible. We have for a long time re-anodized reflectors when anodized reflectors were main-stream, but since then MIRO aluminum has replaced it. So we tested a lot of reflectors too, to see how mucg reflectivity they had lost and if they needed to be replaced or re-anodized. The reflectors of horticultural fixtures can be easily changed, even without removing the lamp from the fixture.

 

You need to remember that about 50% or more of all the light on your crop is reflected light. If your reflector has lost 10% reflectivity then you can replace bulbs whenever you want, but you lose a total 5% of your light before you have even replaced your bulb.

 

In that respect is 4% loss per 5000 hours for a HPS lamp not that bad. A reflector by itself can create a bigger loss.

 

Who replaces his reflector plates every year?

[merl1n]

Hi Chops!

I've always used the 3 crop rule, but in saying that I use the same HPS for grow and flower. Where some ppl use MH for grow which would lengthen the life of the flowering lights.

But I'm very interested in the info from Whazzup. I clean my bulbs prior to starting but hadn't given the shades much thought. Thanks Whazzup, might look into that.

 

Merl1n