All Slope Can and Arc Fault....Bad Combination

Status
Not open for further replies.
Tom
The problem is not the AFCI, it is a grounded neutral which is a NEC violation and a safety hazard even if this fixture was not on a Arc Fault circuit, it would still be a hazard. it just would have not been detected.
As I said the AFCI did it's job, and shut the affected circuit off.

By grounding of the neutral this fixture has placed current on the circuit grounding conductor, and if you have grounding conductors connected in J boxes to other circuit grounding conductors, you now have a few circuits with current on the grounding, now if there is a voltage drop in this circuit you now have a voltage potential between the grounding and earth or another path that would equal earth, this could lead to a shock potential. if someone unknowingly were to open one of these grounding conductors, they could find themselves between live voltage at a time they would expect no voltage, and a lost neutral would go un noticed since the current would still return via the grounding conductor.
 
iwire said:
rp_series_thermal_protectors_1.jpg
Click to expand...

Ok after a little research, I now see what they are:
Self heating thermal protectors.
Generally used in open non-IC rated cans.

the 3-wire ones are used in incandescent and single voltage ballasted lamp fixtures, and the 4 wire ones are used in multi-voltage type fixtures, black is line in, white is neutral, blue is 277 volt tap, red is to the 120 volt tap<<<might have that backwards,

it seems they use a wire wound resistor to heat up if a lamp is used that is higher wattage then the rated lamp, this causes the heater to heat up a bi-metal contact which will turn off the lamp, simple but I can't see how actual heat detection will be accomplished if a lower wattage trim is used, like a glass shower trim which is only rated for a 40 watt bulb, seems to me this system only monitors for current draw, and if the heat in the fixture gets hotter, the lamp current will also get lower as the lamp heats up also because of the filament resistance.
 
A/A Fuel GTX said:
Are you criticising the time it took me to find the fault? A simple continuity test did find the problem on the first go round but it takes time to undo the splices to isolate the fault.
Click to expand...

I can easily see it taking several hours to find a problem like this. Not what you would normally find. And if you do not know what can was first it is rough.
 
I've only used a TDR on long buried telco cable runs to find faults, but I've often wondered if that device could be used in just such a situation as this. Providing you knew or remembered how the cable was routed from which can to the next. A TDR shows splices and faults on the readout, which you may have been able to count the spliced non faulted cans in the readout up to the faulted one. Just a thought.
 
Going back to the OP, I don't think these cans were supposed to be manufactured this way, I think you got a bad batch. (at least I hope that is the case) Personally, I steer clear of Halo. They used to be a lot better before becoming the big box, harry-homeowner special! I will install them when the customer provides them, but I provide Lightolier, Progress or Elite when I have to stand behind the product!
 
macmikeman said:
I've only used a TDR on long buried telco cable runs to find faults, but I've often wondered if that device could be used in just such a situation as this.
Click to expand...
Old school TDRs witha scope can be good as they show each impedance discontinuity as a peak on the scope. The newer clever units just give you a distance, and for multiple faults (like this case) that's not nearly as useful.
 
Ok, here is an update. I finally got through to an engineering type at Cooper and he had me overnight one of the suspect cans to Georgia. They are going to evaluate the can and he even said they would compensate me for my troubleshooting time. I'll post more as the case develops.
 
A/A Fuel GTX said:
Ok, here is an update. I finally got through to an engineering type at Cooper and he had me overnight one of the suspect cans to Georgia. They are going to evaluate the can and he even said they would compensate me for my troubleshooting time. I'll post more as the case develops.
Click to expand...
Nice start but now you have all of them to fix
 
dbuckley said:
Old school TDRs witha scope can be good as they show each impedance discontinuity as a peak on the scope. The newer clever units just give you a distance, and for multiple faults (like this case) that's not nearly as useful.
Click to expand...

That there "old" style is the only type I ever had my hands on. At one point I had the greatest set of manuals on using it to find phone system faults.
About ten books, each one on its own subject related to the usage of the tdr to find faults, and how to make the repairs. Published by Ma Bell. Man, some of the things I have tossed out over the years, if I only knew how I should have kept them....
 
I was triming out a house yesterday and I had a living room circuit that was tripping and the AFCI wouldn't reset. I have two of the same cans in the living room.... I know what I will be doing today. Thanks for the info
 
dSilanskas said:
I was triming out a house yesterday and I had a living room circuit that was tripping and the AFCI wouldn't reset. I have two of the same cans in the living room.... I know what I will be doing today. Thanks for the info
Click to expand...

Let us know what Cooper tells you. They should receive the can I sent them sometime today. We'll get to the bottom of this.........
 
OK....Here's the final chapter. After examining the H745ICAT I sent to Cooper, engineers have determined that a manufacturing line error caused the fault in the can. The lampholder was installed 90 degrees out of the alignment that the specs called for thus creating the neutral to ground short that was the culprit here. The fix is to remove the 8-32 screw that holds the lampholder to the mounting bracket, rotate the lampholder 1/4 turn and reinstall the screw. The short will then be eliminated. The most frustrating part of this ordeal was simply getting to the right person that understood the problem and not some administative assistant that didn't have a clue what I was talking about. I'll bet I told my story 10 times before I finally had success. They are going to reimburse me for the cost of the air freight, my troubleshooting time and the modification time. The only remaining mystery is......how many of these cans are deployed and in use without the arc fault protection that brought this issue to the surface?
 
A/A Fuel GTX said:
OK....Here's the final chapter. After examining the H745ICAT I sent to Cooper, engineers have determined that a manufacturing line error caused the fault in the can. The lampholder was installed 90 degrees out of the alignment that the specs called for thus creating the neutral to ground short that was the culprit here. The fix is to remove the 8-32 screw that holds the lampholder to the mounting bracket, rotate the lampholder 1/4 turn and reinstall the screw. The short will then be eliminated. The most frustrating part of this ordeal was simply getting to the right person that understood the problem and not some administative assistant that didn't have a clue what I was talking about. I'll bet I told my story 10 times before I finally had success. They are going to reimburse me for the cost of the air freight, my troubleshooting time and the modification time. The only remaining mystery is......how many of these cans are deployed and in use without the arc fault protection that brought this issue to the surface?
Click to expand...

I am glad that you got your issue resolved and just compensation for your time. Had you just fixed it yourself and forgot about it other installers would have gone through the same aggravation or possibly gotten hurt/killed in the process. Hats off to you for a job well done.
 
Status
Not open for further replies.
Top