street light trouble shooting

[ce2two]

ever had to find a direct short in underground I.M.C or the it's equal ,turn on the breaker that feeds 15 street lights ,the breaker growels for about three seconds then trips..pull load wire from breaker attach to a 120vac. light bulb, 120watt ,other side of lt to the breaker ...divide 120 into 120 u get 1 amp,go pull box to pull box till the time ,u find a current reading other than 1 amp then u will have found your problem...............it realy works think before you jump in the water...........

 

[electricalperson]

ever had to find a direct short in underground I.M.C or the it's equal ,turn on the breaker that feeds 15 street lights ,the breaker growels for about three seconds then trips..pull load wire from breaker attach to a 120vac. light bulb, 120watt ,other side of lt to the breaker ...divide 120 into 120 u get 1 amp,go pull box to pull box till the time ,u find a current reading other than 1 amp then u will have found your problem...............it realy works think before you jump in the water...........

nice trick

 

[Mule]

u find a current reading other than 1 amp then u will have found your problem...............it realy works think before you jump in the water...........

Im thinking when you find the one that IS 1 amp you have found the ground? Is that what you meant? am I missing something?

Dont change wattage, one would have to think too much? :smile:

 

[brantmacga]

i got a headache reading that, but i think i got the point.

what if i don't have a 120w bulb? can I use a 60w and say .5 amps is the reference?

 

[Mule]

i got a headache reading that, but i think i got the point.

what if i don't have a 120w bulb? can I use a 60w and say .5 amps is the reference?

Or two 60's in parallel...

 

[charlie]

Or two 60's in parallel...

or three 40's

 

[ce2two]

ce2two

ce2two

from #1 pull box say to #9 each one of those ,you clamped the wire and had 1 amp ,every thing was good up to this point ,then u check #10 and found say 40 amps you have found your problem ,it is between p/b #9 and #10.....u can use 2-60 watt lamps ,it's up to u it's your call..............pull out burn't wire ,pull in new ......

 

[Mule]

from #1 pull box say to #9 each one of those ,you clamped the wire and had 1 amp ,every thing was good up to this point ,then u check #10 and found say 40 amps you have found your problem ,it is between p/b #9 and #10.....u can use 2-60 watt lamps ,it's up to u it's your call..............pull out burn't wire ,pull in new ......

My bad, I was clamping on to the wires going up the pole in my brain
(or the lack of) You said the short was in the underground not the ballast...duh.....yep you've got a good system there.

I've used Amprobe's T1000 I think thats the part number? anyway its a good ground locator also for problems such as that.

 

[LarryFine]

then u check #10 and found say 40 amps you have found your problem

How do you get more than 1a through a 120w bulb on 120v?

 

[Mule]

How do you get more than 1a through a 120w bulb on 120v?

40amps....Had to be a senior moment or a typo !!:grin:

 

[hillbilly]

from #1 pull box say to #9 each one of those ,you clamped the wire and had 1 amp ,every thing was good up to this point ,then u check #10 and found say 40 amps you have found your problem ,it is between p/b #9 and #10.....u can use 2-60 watt lamps ,it's up to u it's your call..............pull out burn't wire ,pull in new ......

I completely misunderstand:smile:

steve

 

[buddhakii]

Wouldn't it actually drop down to zero after p/b #9? After the circuit is completed in the u/g with the conduit or other grounded conductors you should have no current flow after that point. This is kind of like troubleshooting shorts in an old fuse panel. Light bulb screws right into the fuse holder and when the light goes out you found your short.

 

[jrannis]

Seems like it would be kinda tough to get 40 amps through a small light bulb