Ceramic Metal Halide (CMH)

[simba]

chili,, yes you can.Not the way u say just a bit dif..
using regular relay and HV-Pulse Rated Relay and timer..
but honestly after u get done buying that hv-pulse relay reg relay.. plus the one ballast
u coulda bought 2 ballasts
it would actually power the ballast off for a split-second, at that same time the hv relay would kick over to the other bulb it would be instant..
let me know if u need a schematic of the Switch box..setup.. (i dont Really recommend,, you may get a mis-fire or two..)


bonsai ya. give me till tomarow. to find it.. sorry.

 

[chiliwalt]

Thx Simba and mess'n'gommin', yes I think I will take your advice Simba and go w/ ballast per light. the grow space is divided into 3 equal areas and will run 24/7. 2 of the divisions are grow areas, the 3rd a lung/air-mixer. The entire room is sealed airtight, w/ split a/c and co2. One grow area will run 12 hrs., then the other area will run 12, consecutively, this minimizes temp. changes and therefor less humidity. A few mis fires really wouldn't kill me as I'll have more than adequate coverage, still another concern is going from 10 ballasts to 20 increases heat quite a bit.

 

[Frosy]

Thanks for this awesome post! What about using electronic ballasts with these?

 

[Frosy]

whoops, let me be more clear, I just ordered 2 of thw 400 watt Phillips CMH bulbs, now I need to get correct ballasts. What would ya'll recommend?

 

[simba]

Frosy.. Get Basic HPS magnetic Ballast. (standard HPS ballast for 400 watt sont)
as far as the heat from 20 ballasts. you can Air Cool them..(make Ballast Rack Box (Non Flam Materials) with CPU heatsinks on them with few Fans pushing air threw ( you could use the room air to go into box and from box via pvc to outside.. (so ballasts wont heat up room at all)
im trying to work on Oil cooling the ballasts but the cpu heatsinks work great..

 

[Frosy]

Thanks Simba, the basic magnetic ballast is what I need then. Are the digital ballasts unsuited for the CMH? I was hoping to try one out. either way I am looking forward to my next grow, moving up from fluorescents...

 

[simba]

Ya frosy, 99% of the Digi ballasts out there WONT work with CMH (cmh requires 40-240Hz) and most 99% of digis out there are 450hz (mag core ballasts are 50hz for euro and 60hz in usa/canada)
/ im not a fan of ANY digi ballast out there (except the GE ultra max and adv tech RD one but either one u better have 20+ to be economical in the end)
electronic IMPHO is really for 5-150 watt CMH, MH, HPS (untill cost comes down and relability goes up) they require clean power.. (most houses arent)

 

[Frosy]

Thanks Simba, you are truly a master of lighting tech knowledge. I wont get another grow in till fall, but when I do I'll burn a fattie in your honor.

 

[chiliwalt]

thx simba, I'll only be running 10 @ a time, might just jam em outside..

 

[przcvctm]

I'm about to wire up a new digital timer (Grasslin digi 42) to follow my relay and delay on timer. From the price I paid for it you'd think it should handle the 4amp load of my 400w ballast, but I just wanted to check here first before I put it all together.

The technical data doesn't make it easy and just spell out maximum wattage, but provided the following:

Output-SPDT relay with dry contacts
Switch Rating-16A/277VAC resistive
1000w tungsten @ 240VAC; 500w tungsten @120VAC
1/2 hp @ 120VAC; 1hp @ 240VAC

Do any of these specs mean anything to anyone that wouldn't mind helping out?

 

[simba]

Prz,
but you should be good..
(only have your lamp on that)

 

[przcvctm]

Is it cutting it too close, simba? I ask because you edited and left a "but" at the begining of the sentence.

 

[Guest]

So I finally picked up a few of these bulbs to trade out my 400w hps's. I am having issues with one of the ballasts - either the bulb won't fire, or it looks kinda dim?

Identical ballast to the others that work fine. Any suggestions?

 

[FreezerBoy]

Assuming you've swapped lamps between ballasts, insuring both lamps are OK, my first guess would be they're HTG ballasts with weak ignitors.

 

[simba]

StrainWHore, Run them for 12 hours then compare again..
could be just color shifting.

Prz, ya, ya kinda are cutting it close.. (the ballast should pull about 430ish while runing and a bit more during strike (Strike is same time as relays are Switching possibly creating an arc as its a Huge inrush while the contacts are still closing) they are rated 500w incan @120v thats about really close to 400ish in HID if u where to compare...
the reason every thing is double at 277 is because when u step to that voltage you are now using 2 hot wires to carry the instead of 1 wire and that distributes the load evenly so they each carry that rating of 500w tungsten/ 1/2hp motor . if that makes sense..
thats the shortest way to say it..
but i think u should be just fine..

 

[Guest]

FreezerBoy - did that... Yep.

Simba - have done, still dim...

 

[simba]

SW.. so im clear.. you have swaped bulb from one ballast to another and that bulb is dim no mater what ballast its on.. or is it only being dim on one of the ballasts..
You are SO eligible for replacement if its dim on both ballasts.(even if dim on one but other things to look at then)

 

[Guest]

Simba - I flip flopped bulbs between ballasts and both bulbs were dim on that ballast, it's definitely the ballast. Could that be a fixable issue - or is it time to replace the ballast?

 

[MPL]

I would say replace, as I do not believe it is the igniter or the capacitor that would cause it to be dim. Small possibility on the capacitor, but unlikely in my opinion.

Simba - I flip flopped bulbs between ballasts and both bulbs were dim on that ballast, it's definitely the ballast. Could that be a fixable issue - or is it time to replace the ballast?

 

[simba]

Hmm.. Depending on the issue yes or no..
could be the cap failing as that is what holds/determines the wattage Output to the bulb
Capacitor in a CWA Ballast is the Wattage controller/ regulator.. If that makes sense..
we use different size caps to dim ballasts (short version)

what brand ballast/age..
how much dimmer.. (just a q not relivent, well kinda)

is the ballast a diy kit.. is it dim with HPS bulbs..
it could be cap or the power inputs are on the 220 side and should be 120.. a 400 cmh will fire and run with a 250 watt ballast.. be dim but fire

Super short ballast diag..
if nothing has changed in wiring.. from going good to having issues (only change might be a new bulb) and assuming u keep clean contacts.
failing to start.. and stay runing
ignitor prob or cap
dim output. cap is prob failing.
the core itself mainly when it fails is cause of Over heating (IE shorting out) wont do any thing exept blow fuses)
caps and starters will be replaced at least once in a Ballasts Total Life
Core should at least go threw 1-2 set of caps or starters or both (the cooler the core is kept the longer it Lives..


LAMP LIGHT OUTPUT LOW

POSSIBLE CAUSE

CORRECTIVE ACTION

1. Normal Light Output Depreciation Throughout Life

Refer to maintenance characteristics of lamp in technical publications comparing light output vs. burning time. If depreciation is within published range, replace lamp.

2. Incorrect Voltage

Check ballast label to see if rating designation conforms to lamp rating description. Correct if necessary. Check line voltage at ballast and set ballast tap to voltage reading. If not tapped, check ballast voltage range against input voltage. Check wiring connections for voltage loss points. Check socket contact point. Use CWI ballast.

3. Incorrect Ballast Output

Check ballast output to determine if it conforms to lamp requirements. If voltage and current do not stabilize in five to ten minutes warm-up time, ballast output is incorrect and adjustment should be made. Check capacitor wiring, if visibly available, to determine if capacitors are properly wired.

4. Dirt Accumulation

Check and clean lamp and luminaire. Establish maintenance program.

5. Faulty Capacitor

Check capacitor rating to specification. Measure capacitance to specification using capacitance meter. Replace capacitor if necessary.


Side Note On extending ballast.bulb life..
(Ceramic Metal Halide & Probe&Pulse start Metal Halide only) This condition is unique to the Ceramic Metal Halide and standard Probe&Pulse Metal Halide lamp. It does not occur with Mercury . If the supply voltage to the lamp is interrupted during the warm up period, the subsequent restrike voltage (voltage required to restart the lamp) may be higher than that required for a lamp which has been allowed to stabilize (come up to full output normally) or to cool down to normal room temperature before the restrike..