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Discussion Starter · #1 ·
I know we do not see VHO very much these days. I came across an interesting problem and just want to know if someone had any suggestions or answers.
I just posted the same question over at the G rated forum.
Maybe here at the corner bar forum, our outlaw barkeep or patrons, might be able to help with some wisdom.

I went by a customers shop late yesterday to drop off some paperwork.
The building is just about 10 years old.
The shop area with 20' ceilings and a loft, has about 25 or so 2 lamp VHO fixtures.
The customer is loosing about 10 ballasts per year.
I checked a spare ballast, it is good for one or two F96T12VHO lamps
I looked at several fixtures and found one that had just turned off due to the internal thermal overload in the ballast.
I observed two new lamps in the fixture, F96T12VHO and a new, but very hot ballast in the fixture.
The fixture is mounted on bar joists and has plenty of ventilation.
The ballasts are rated for "outdoor"
The lamps turn dark at the ends after a short time in service.

Question:
I remember servicing VHO fixtures many years ago and didn't think that their was anything special about them. Some would even be date stamped 20 or 25 years old.
The customer has been buying both the lamps and ballasts at Grainger. I saw the box the lamps came in and looked at a ballast he had new in the box. They match.
What am I missing?
 

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I had the same problem some years ago and we traced back to some new bulb sockets we had bought. They looked just like the factory ones but were wired different inside. So when we put them in just like the old ones we were actually shorting the ballast. The doggone things would light for quite awhile before the ballast overheated and shut off, then they would come back on. Drove us nuts. Try your ohm meter on the bulbs sockets. Long shot but you never know!
 

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Discussion Starter · #3 ·
I didn't have time to check all of the terminations. The fixtures looked new but they could be miswired. Who knows who changed the ballasts.
If they did one wrong and kept changing the same ballast color to color it would product that symptom.
 

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Bandwidth Conservator
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I have an installation like this where I added several fixtures next to some existing units. I noticed during the install that one area of existing fixtures did not have solid grounding back to the service because the EMT had seperated. The owner told me several months later that those particular fixtures go thru the H/O bulbs very quickly compared to the solidly grounded fixtures I installed. I believe it affects their start-up. Maybe I'm wrong. That's OK - I'm here to learn ;)
 

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Instead of fixing the VHO fixtures, perhaps it would be time to up sell a more efficient lighting system, VHO's are a power hog.
 

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The fastest way to kill the VHO's is use the wattmiser or reduced wattage bulbs that useally is the #1 curpit the reason why due the reduced wattage bulbs have little more higher operating voltage to keep it running.

Really seriously., I think you should suggest the customer to get new luminaire like new flourscent low/high bay for power usage it will be less but you will get heckva more light to boot.

I know old VHO if full rated bulbs they are rated at 215 watts each so for two lamp luminaire you have 430 watts and add the ballast load so you are looking about 460 to 500 watts range and dish out about 13,000 lumines each so total about 26000 lumines per luminaire The MH can do much better light than this one however before you go with the MH go with flourscent Hi/Low bay lumiare with 6 lamp 32wT-8 it will dish out more light than old school VHO and much quieter to boot so you don't have to hear the buzzing noise of VHO ballast.

Check with Your POCO they may have some type of rebate or something to help to reduce the luminaire load pretty easy.

Merci,Marc
 

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Wyome
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flourscent Hi/Low bay lumiare with 6 lamp 32wT-8

Check with Your POCO they may have some type of rebate or something to help to reduce the luminaire load pretty easy.

Merci,Marc
Or 32wT5's. Incredible light output. High dollar though. The local power co here does have some good rebates for commercial or industrial applications
 

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What sort of facility is using VHO's? Is this a cold-storage facility? If not, I'd check the summer ambients at 20' off the deck and compare that to the specifications of the ballast. VHO's run blazing hot anyhow, then put them in a super hot ambient in the summer and they could be stewing in their own juices.
 

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Discussion Starter · #10 ·
They are located on the barjoists of a 20' high warehouse.
The customer is a glazing contractor and has metal working hand tools much like we do. He hole sawed holes through the back of the fixtures behind the balast to "let the heat out".
I think he should go with the T8s personally.
Still doesn't solve the mystery.
I think the smart money would be that they aew miswiring them when they change the ballasts or maybe "upgraded" themselves to VHO and left the HO sockets in place.
 
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