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Posted By: menegt walkway light poles on campus - 03/14/02 01:28 AM
Situation: Many light poles in campus walkways. 3 circuits (277V) feeding them. At times ballast go bad and circuit trips or bad connection in cristie(sp) box. Spend many hours tracing to exact pole(s)

Problem: How to save time in finding correct pole which is bad. When the circuit trips it trips the hole bank of lights (20) lights or so per leg (HPS 100W). I was thinking of putting some sort of in-line fuse w/ a popout indicator on each pole. What do you guys think any suggestions? It's a real hassle trying to peel of switch legs here and there. There's about 20 Christie boxes.... Any suggestions?
Posted By: Redsy Re: walkway light poles on campus - 03/14/02 12:03 PM
What is a christie box?
Posted By: The Watt Doctor Re: walkway light poles on campus - 03/14/02 03:10 PM
I would mark the poles that represent 1/4, 1/2, and 3/4 points on the circuit. Everytime you have a problem on that circuit, go to the pole that represents the halfway point on the circuit, and break the joints. Go turn the breaker on. If the circuit breaker trips, you know the problem is on the first half of the circuit. If it doesn't, you know that the problem is on the second half. Remake the joints at the halfway point, and go to either the 1/4, or 3/4 point, and start the process over again.
This is know as "half splitting".
Good Luck.
Regards,
Doc
Posted By: menegt Re: walkway light poles on campus - 03/15/02 01:25 AM
Thanks Doc, good advice. Unfortunately at the University, before I got there there have been many runs which have been re-pulled, conduit abandoned and backfed... it's a real mess. The best I/We could do is disconnect at a halfway point which you mentioned and at this point 20 or lights are out and it's like trying to find a needle in a haystack. We certain sectors in the campus which are broken up exactly the way you have mentioned. Troubleshooting not too bad on that one. I was just wondering if there was a way to install some sort of pop-up indicator on tha actual pole or via an inline splice or something. I know I could physicaly install it but does this sound kind of McGyver-ish?

Mike
Posted By: resqcapt19 Re: walkway light poles on campus - 03/15/02 02:15 AM
Why not just use the inline fuses at each pole. You don't need any type of "popout indicator". Just turn the power on and look for the fixtures that aren't lit.
Posted By: menegt Re: walkway light poles on campus - 03/15/02 03:46 AM
Yes.... very good idea. Thanks.
Posted By: electure Re: walkway light poles on campus - 03/15/02 12:58 PM
Does anybody have a good source for the inline fuseholders? I've had some trouble locating good, UL listed ones for this application in the past.
Posted By: resqcapt19 Re: walkway light poles on campus - 03/15/02 04:50 PM
electure,
Look at Bussmann's HFA series for 250 volts or less and the HEH series for 480 volt applications. The HFA products are UL recognizied and the HEH are CSA certified.
Don(resqcapt19)
Posted By: Scott35 Re: walkway light poles on campus - 03/16/02 01:26 AM
Menegt,

I like your fuse idea. That would help identify one or more overloading fixtures.

I have a feeling that these Ballasts do not have a Power Factor Correcting Capacitor installed. Have recently installed some new Hubbell HPS fixtures [100 watt HPS - ANSI S54 lamp] and there was no Capacitor included.
That makes the PF only 50%, so there's close to 2 times more current drawn.

I included this to give a possible fix - try installing Capacitors to lower the Line Amperes / KVA.

Scott SET
Posted By: Redsy Re: walkway light poles on campus - 03/16/02 03:08 AM
What is a christie box?
Posted By: menegt Re: walkway light poles on campus - 03/16/02 03:20 AM
christy boxes are just inground boxes used for splices, grounding electrodes etc.... just like fiberlites (sp) but rectangular....
Posted By: menegt Re: walkway light poles on campus - 03/16/02 03:26 AM
Scott, what should I check on the fixture? I'm pretty sure that the walkway fixtures we have do include a capacitor and transformer. How would I incorporate the capacitor you're talking with an inline fuse set-up?
Also, in picking out the fuse you're saying I should double the amperage rating of the
fuse? Thanks.....
Posted By: Frank Cinker Re: walkway light poles on campus - 03/16/02 02:05 PM
Scott,

I thought all HID fixtures came with a capacitor. I know the HID ballast replacement kits I purchase have one.
Posted By: Scott35 Re: walkway light poles on campus - 03/16/02 05:32 PM
Menegt,
Place the Capacitor across the Ballast's Line input [277 VAC in] and the "Common".
I'll find out the size to use for 100 watt HPS.

Your fuses should be as close to the rated amperage as possible - with a 50% maximum tolerance.
If the total amperage was 1.0 amps @ 277 VAC, size the fuse at 1.25 amps [low end] or 1.5 amps [highest].
This will cover changes in line current [KVA] if the voltage drops.

Frank,

I never saw any HID ballasts in the last 8 - 10 years that did not include PF correcting Capacitors [new fixtures], however I installed two Hubbell HPS 100 watt fixtures this week and they did not have PF Caps!
There was also an existing 150 watt HPS fixture which also had no PF Cap!
I couldn't believe my eyes!!!
even better was the 4.4 amperes that was rated for the 150 watt HPS at 120 VAC!!!

I'm gonna try to talk my Company into putting PF Caps in these fixtures, just to put my mind at ease [Linked Image]
I have an assortment of HID Caps, so no one would need to buy new Caps.

Scott SET
Posted By: electure Re: walkway light poles on campus - 03/18/02 11:27 PM
Don,
That was the deal.
I can't use a CSA certified fuseholder here, can I? The problem I've run into was with 277V fixtures, and lack of an UL listing.
Posted By: resqcapt19 Re: walkway light poles on campus - 03/18/02 11:43 PM
CSA is a NRTL in the US.
Look at this site: http://www.osha-slc.gov/dts/otpca/nrtl/nrtlsite.html
Don
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