240v reading
#1
06-08-20, 05:33 PM
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240v reading
does anyone know why I have 240v reading after the meter but not at the bus bars I checked line 1 and line 2 they both read 120 but not 240 inside the panel
#3
06-08-20, 05:51 PM
Group Moderator
They read 120 volts to ground because you have a two-pole breaker that is on. You are reading through a 240v load like a water heater. If you turn off all the two-pole branch circuit breakers you will find out you have one leg that is not hot.
#4
06-08-20, 06:29 PM
Not sure what you re reading but here is how it works.
Basically you have two 120 volt supplies when measured to Neutral.
So L1 to Neutral = 120 volts and L2 to Neutral = 120 volts.
But the two supplies are 180 degrees out of phase.
So when L1 is at -120 volts, L2 is at +120 volts.
Therefore L1 to L2 = 240 volts
Basically you have two 120 volt supplies when measured to Neutral.
So L1 to Neutral = 120 volts and L2 to Neutral = 120 volts.
But the two supplies are 180 degrees out of phase.
So when L1 is at -120 volts, L2 is at +120 volts.
Therefore L1 to L2 = 240 volts
