harley
Member
- Location
- Pennsylvania
A simple OHM METER can solve tripping problems.
Turn off breaker and disconnect load neutral from
breaker and connect to OHM METER. Connect other
lead of OHM METER to ground/neutral bar (main panel) and reading S/B hundreds of k ohms, or meg ohms if reading 0 ,1, or 2 ohms you have a
grounded neutral or shared neutral. If you have 0 ohms (short) check bare ground wire on neutral screw or pinched neutral on lite canopy. Use OHM METER in middle of circuit by disconecting neutrals and ohm neutral to ground and seeing which direction problem flows. Share neutrals happen all the time when 3 way switches are used
in large ganged switches. Two feeders are used in multi-ganged switches on seperate walls and it is very easy to tie all neutrals together and not keep circuits seperate.
After installing AFCI's always test with a LOAD. I use @ least 100 watts for this checks the 30 ma circuit which acts like GFCI. IF you have a grounded neutral GFCI trips immediately without load AFCI needs a load applied for the 30ma to function.
AFCI's and SUB-PANELS act a little different for any load (non-AFCI) can trip a AFCI grounded neutral. Current from a standard breaker returns on the it's neutral back to neutral conductor to main panel neutral/ground BUT it also back feeds thru the pig-tail of the AFCI with the GROUNDED NEUTRAL tripping the AFCI. That is why a AFCI will trip when applying a load on a different branch circuit when it pertains to SUB-PANELS.
Turn off breaker and disconnect load neutral from
breaker and connect to OHM METER. Connect other
lead of OHM METER to ground/neutral bar (main panel) and reading S/B hundreds of k ohms, or meg ohms if reading 0 ,1, or 2 ohms you have a
grounded neutral or shared neutral. If you have 0 ohms (short) check bare ground wire on neutral screw or pinched neutral on lite canopy. Use OHM METER in middle of circuit by disconecting neutrals and ohm neutral to ground and seeing which direction problem flows. Share neutrals happen all the time when 3 way switches are used
in large ganged switches. Two feeders are used in multi-ganged switches on seperate walls and it is very easy to tie all neutrals together and not keep circuits seperate.
After installing AFCI's always test with a LOAD. I use @ least 100 watts for this checks the 30 ma circuit which acts like GFCI. IF you have a grounded neutral GFCI trips immediately without load AFCI needs a load applied for the 30ma to function.
AFCI's and SUB-PANELS act a little different for any load (non-AFCI) can trip a AFCI grounded neutral. Current from a standard breaker returns on the it's neutral back to neutral conductor to main panel neutral/ground BUT it also back feeds thru the pig-tail of the AFCI with the GROUNDED NEUTRAL tripping the AFCI. That is why a AFCI will trip when applying a load on a different branch circuit when it pertains to SUB-PANELS.