ballast or bulb

[electricalist]

When working on lighting that is metal halide, high pressure sodium or mercury vapor.
Does anyone have time to explain the basic difference in these. Are any of these interchangeable and what's the best method to determine if the bulb or ballast is bad other than swapping bulbs. (Sometimes it will blow out a new bulb).

 

[iwire]

When working on lighting that is metal halide, high pressure sodium or mercury vapor.
Does anyone have time to explain the basic difference in these. Are any of these interchangeable and what's the best method to determine if the bulb or ballast is bad other than swapping bulbs. (Sometimes it will blow out a new bulb).

It won't blow out a good new bulb and in my opinion swapping lamps is the most efficient method.

 

[iwire]

This is a handy guide, print it out and keep it where you can get it when needed

http://media.hydroponics.net/productdocs/HID_Pocket_Guide.pdf

 

[electricalist]

Last year we were doing a parking lot with 150 pole lights . we turned them on counted bulbs not on. I started by replacing bulbs . too many new ones blew out to keep doing it that way. I don't know enough about these type of lights to know why they blew out but it cost more than its worth to test a ballast that way. Thank you though.

 

[electricalist]

This is a handy guide, print it out and keep it where you can get it when needed

http://media.hydroponics.net/productdocs/HID_Pocket_Guide.pdf

It says can't open file on my tablet. I'll try it on my phone

 

[iwire]

I started by replacing bulbs . too many new ones blew out to keep doing it that way.

This does not make any sense whatsoever. :huh: There is no reason for that to happen.

Every parking lot lighting service guy I know does the lamp swap first, if a new lamp does not light then you go deeper.

 

[electricalist]

This does not make any sense whatsoever. :huh: There is no reason for that to happen.

Every parking lot lighting service guy I know does the lamp swap first, if a new lamp does not light then you go deeper.

I wasnt sure thats why I asked.

 

[electricalist]

Thanks Mr. IWIRE it worked on my phone

 

[Dennis Alwon]

This does not make any sense whatsoever. :huh: There is no reason for that to happen.

Every parking lot lighting service guy I know does the lamp swap first, if a new lamp does not light then you go deeper.

Bob I have had situations with fluorescent bulbs blowing out when switching bulbs. It seemed like the ballast was somehow putting out too much-- not sure but if I changed the ballast and used that bulb it would not work. I then used another bulb from the box and it worked. I have seen this happen more than once... Maybe I am nuts but something was odd

 

[iwire]

Bob I have had situations with fluorescent bulbs blowing out when switching bulbs.

I think the OP was talking about HID lamps, but I am just as puzzled by your observation as well. :huh:

Could it have just been a bad lamp that would have gone out when put in dead and tuned on at the switch?

I just cant see how a ballast could blow a correct type lamp immediately. :huh:

 

[Dennis Alwon]

I think the OP was talking about HID lamps, but I am just as puzzled by your observation as well. :huh:

Could it have just been a bad lamp that would have gone out when put in dead and tuned on at the switch?

I just cant see how a ballast could blow a correct type lamp immediately. :huh:

I realized the op was talking about HID but I figured if my experience with fluorescent ballasts was similar maybe there is something to it. Of course it is possible the bulb was weak- but it has happen a number of times- maybe 5 or 6 times in my career. Bulbs were taken from the box at the supply house but who knows. I don't think I ever tried two bulbs-- changed the ballast and tried the first bulb and no good then another from the box and it worked. You could see the ballast was leaking in a few of those cases so I am quite certain the ballast was bad.

I was puzzled by it myself and just said oh well/

 

[electricalist]

Mr. Dennis when my boss came by I told him what was going on and he said hmmmm. And just looked at me.. he brought a box of lamps that came from a demo that were same watts. . All were working when put in box. We used most of them up as test lamps.

On a 400 watt 480 v ballast what is output voltage at socket.? 960

 

[electricalist]

So what I looked up the minimum start up volts can be 540 @ 380 rms. Does anyone test volts at the socket. I never have. One thing I read is that a pulstart ballast will blow out a new bulb if its not a pulse start bulb

 

[kwired]

Each lamp type has different electrical input needs. It takes a different voltage to start the arc in each different lamp as well as a different voltage to maintain the arc. Open circuit voltage at the socket will be different then starting voltage as well as different then running voltage.

Each lamp type needs a ballast that is designed specifically designed for that lamp type and wattage.

Pulse start does send a higher pulse of starting voltage to the lamp then what is sent to a probe start lamp, I could see there being a chance of doing some damage if you use the wrong lamp. Pulse start has replaced a lot of probe start applications and you need to watch for cases where maybe a ballast had been changed from probe to pulse start even though lamp wattage remained the same.

Some ballasts will drive both a mercury vapor and a metal halide lamp of same watts, but otherwise lamp and ballast must be a match to one another. Mercury vapor is about extinct anyway and you will only deal with them at existing installations.

 

[electricalist]

Ty Mr KWIRED . Your help is like listening to electricity itself.

 

[tom baker]

Can screw in an incandescent lamp and if it works ballast is OK.
We have hundreds of HPS and MV luminares, change the lamp, if that does not do it, change the ballast.
There is a screw in ballast and lamp tester you can get, has diagnostic lamps.
But all the above is obsolete as we are changing to LED as they fail.

 

[kwired]

General rule with HPS was always if an incandescent lamp works in the socket the ignitor was likely bad.

Apparently voltage on a HPS lamp is close enough to 120 volts that an incandescent lamp will work fine, at least those typically using a medium lamp base.

 

[Little Bill]

Ty Mr KWIRED . Your help is like listening to electricity itself.

Is that like watching paint dry or grass grow?
Or more like fingernails down a blackboard?:dunce:

 

[electricalist]

Is that like watching paint dry or grass grow?
Or more like fingernails down a blackboard?:dunce:

I am a dunce cause I have no clue what you mean. KWired has answered many of my trivial questions so I say it like getting the answer from its origin. Mostly it just means thank you sir for your time and knowledge.