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| Subject - Finding Bad Fluorescent Ballast | |
| Romex Racer |
If you have 10 fluorescent fixtures wired together, like in a warehouse or something. If the ballast in one of those lights shorts out, it will trip the breaker and all the lights will go out. Now you have to open up every fixture, disconnect it and try the breaker to see which ballast is bad... A very time consuming job. Here's how to identify the bad fixture in seconds: Take the wire off the breaker and hold it against the bus. The bad fixture will be the one with the smoke and sparks flying out of it! In 27 years of wiring, I've done this a few times and it works every time! I know this isn't pretty, and some may blanch at the idea, but I learned this from an old hand who was the best electrician I've ever known. |
| Scott Vickrey | Being a creative type I can appreciate the fact that sometimes good results can be had from visionary methods. Some better than others I have no doubt that this method is fast and very effective. However, you know this is not the type of troubleshooting that can be condoned due to it's inherent danger to life and capitol. I can't say I have never seen anyone do this but, There is always a better way than this regardless of the time consumed. If I was on a submarine approaching crush depth I might be able to justify this expiditious method. I feel confident in saying that this is not the way to go. When you start an arch flash you are inviting all kinds of bad possibilities because things that normally serve as insulators (like air) are temporarily ionized to effectively become conductors. A real wrench in the system. This post reminds me of a guy I new that would short out the circuit and trip the breaker to label the panel(first journey I worked with) Effective? Sure. Good Idea? No. There are better ways!
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| Romex Racer | I also have a method to check the level of fuel in your gas tank when the gauge fails. It uses common household matches! :) |
| lctrc789 | I know what you are saying this is out of the ordinary and in 24 years I have seen some pretty dumb, unsafe practices, but some of the old timers well you know what they say you can check voltage between two fingers LOL I have seen some of the old timers check for shorts in many ways, the best one I have ever seen is the old knob and tube wiring shorting out in a house and he had several of the circuit type fuses that reset with the reset button in them. He had me stay at the fuse box while he went upsatirs and then he called to me and said push the reset button and keep hitting it till I say stop. I did, it kept tripping I kept resetting, you know what he found the problem after the wire burned out LOL but never the less he found it. Of course I forgot to mention the fact that the atiic was smoking lol. |
| fgw | I've witnessed the "bypass the breaker" method of chasing down a bad ballast. True, it will work.... I've seen it with my own eyes. I thought the guy I was working for at the time was a little strange however, I learned alot of what I know about pipe work & circuit layout from him. I could never find the courage to try his method. Besides, I can make more on the job if I open each & every fixture to inspect or replace a ballast. Anyone have a "safer" method of chasing down a bad ballast on a string of fixtures? I'm always willing to learn & try new troubleshooting methods... |
| karlwayne | I am probably shooting from the hip, but I know there are people out there who know for sure. I think the ballasts manufactured after 1984 all have thermal protection in them. This may have been an excellent opportunity to make a sales pitch? |
| kbsparky | Engaging in such "troubleshooting" tactics can indeed work in some scenerios, depending on the nominal system Voltage, and available fault current. I would not recommend this procedure on 277 Volt systems, where the flash from the short on the buss bars could result in more than you bargained for. On systems that had a high available fault-current (even at 120 Volts), the short can also produce more arcing and damage than you were prepared for ..... oY! |
| Romex Racer | One time I was installing a light switch for some 277 volt fluorescents, doing it hot, accidentally touched the hot screw to the plaster ring and POW!!!! It was most impressive. I was too young in the trade to take the precaution of wrapping the switch with electrical tape.. Somebody mentioned shorting out a wire to find the breaker in a panel, I used to to that until I learned my lesson. I was working in a house owned by a famous female singer with a large nose and liberal politics, I shorted out the wire, sure nuff, no power, I go to the panel, all the breakers are on and passing power. After 3 hours of trouble shooting I found a loose wirenut that had "arc'd open"... I never did that again! |
| CooCooMike | the old smell test used to do it for me now with the electronic ballasts it's a little bit tougher but one way we used to test for shorts on 110 was using a 200 watt bulb.either screw it into the fuse holder or use a temp socket, full bright was a dead short,saved on fuses and resetting |
| John A. Peters | quote: Right. And then you could use an ampprobe to check for current along the circit, until you find the location of the short. Amperage means look farther away from the breaker, no amperage flowing means check closer to the breaker. Using a voltage sniffer might fool you, does any one know? |
| CooCooMike | never used an amprobe for that application but sounds like it might work |
| CooCooMike | one method i read was that people short out the ct to see which cb tripped. i remember hearing years ago that the manufacturer voids the warranty on a breaker after a direct short |
| skynrd | I would never condone the method of taking a shorted devise to the main buss for any reason. Example from experieince I was installing metal pancake mold in an arcade, through all the devices in and proceeded to hookup the breakers in a 200a sub panel while the place was open for business no problem my 20a breakers that I was hooking up were shut off. Anyway I stripped one wire turned my head to pickup my screwdriver the wire slipped out of my hand and hit the main lug. It just so happened I was lucky enough to drop the wire that was pinched to ground in the pancake mold. It only took 3 months for the burns to heel and the hair to grow back on my arm. But what the hell doctors need to make a living too. |
| DavidSeattle | I was tught to open a shorted circuit at half of its length , if that can be easily determined. In a string of lites that's no problem. Try to re-energize, If the circuit is oksy the problem is in the second half of the installation. Cut that in half and re-energize.Has the problem occured again. a simpler and safer method |
| marxlaws | quote:omg lol- thats rich i hope no 1st years read this answer. what if the short is a broken pipe in the wall? what if the ground is.. what if.. what if ...man, good luck with that. |