3.6 Other
functions
3-11
Functions
Reverse phase
PMU1A
(Electric
power)
PMU2A
(Power
two-system)
EMU8A
(Pulse/temperature)
CTD8E
(CT
expansion)
{
× ×
: With two-system
O: With function
X:
Without function
Reverse phase means that the phase order of voltages is not normal.
When the phase order is normal, phases R, S, and T are 0
°
, 120
°
, and 240
°
, respectively,
with reference to phase R. If a measurement of the relationships between differences in
phase indicates that the condition is broken and then the broken condition continues for 0.1s
or more, it is judged as reverse phase.
Reverse phase can be used to confirm problems in facilities or wrong wiring.
* Since the condition where phases are not normal is judged as reverse phase, phase-loss
may be judged as reverse phase.
Normal phases
Reverse phase
Phase R
Phase S
Phase T
Phase R
Phase T
Phase S
