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Ceiec Electric Technology
control of a Digital Output and may be useful in providing a generic alarm output signal. However,
the sharing of a Digital Output is not recommended if the user intends to generate a control signal in
response to a specific setpoint condition.
4.1.3 Energy Pulse Outputs
The PMC-630E comes standard with two front panel LED Pulse Outputs for kWh and kvarh pulsing.
Energy pulsing can be enabled from the front panel through the
EN PULSE
setup parameter. Energy
Pulse Outputs are typically used for accuracy testing. The pulse constant can be configured as
1000/3200/5000/6400/12800 imp/kxh. The pulse width is fixed at 80ms.
4.2 Power and Energy
4.2.1 Basic Measurements
The PMC-630E provides the following basic measurements with 1 second update rate:
3-phase voltage and current
3-phase power and power factor
Neutral current (I4) and Frequency
Bi-directional energy measurements
Voltage and Current phase angles
4.2.2 Phase Angle
Phase analysis is used to identify the angle relationship between the three-phase voltages and
currents.
For Wye connected systems, the per phase difference of the current and voltage angles should
correspond to the per phase PF. For example, if the power factor is 0.5 Lag and the voltage phase
angles are 0.0°, 240.0° and 120.0°, the current phase angles should have the values of -60.0°, 180.0°
and 60.0°.
For Delta connected systems, the current phasors lag line-to-line voltage phasors by 30°. For
example, if the total power factor for a balanced 3-phase system is 0.5 Lag and the line-to-line voltage
phase angles are 0.0°, 240.0° and 120.0°, the current phase angles should have the values of -90.0°,
150.0° and 30.0°.
4.2.3 Energy
Basic energy parameters include active energy (kWh), reactive energy (kvarh) and apparent energy
(kVAh) with a resolution of 0.01 and a maximum value of ±999,999,999.99. When the maximum
value is reached, it will automatically roll over to zero.
The energy can be reset manually or preset to user-defined values through the front panel or via
communications.
