
Product characteristics
Over Current
Overvoltage protection detects the voltage levels and operates if they are greater than the setting to protect the sensitive loads or
circuits against such condition.
Under Voltage
If the voltage levels fall below the setting the Undervoltage protection issues a warning or
trip signal to protect the sensitive loads such as a inductive motor.
Phase Fail/Phase Unbalance
This protection operates if the percent phase-to-phase voltage unbalance is greater than the setting.
Used to prevent an excessive vibration of three-phase induction motor and a damage of the stator and rotor windings.
This function is disabled under a single-phase mode.
Reverse Phase
This protection operates if the percent phase reversal voltage is greater than the setting.
It detects when the motor is starting. This function is disabled for a single-phase mode.
Over Power
The overpower element operates if the three-phase active power exceeds the setting level.
This element can be used to prevent the power from entering the generator before disconnecting from the system
when the generator operation is finished.
Under Power
The underpower element operates if the three-phase active power falls below the setting level.
Over Power Factor
The over power factor element operates if the power factor exceeds the setting level.
If the load is very small, especially for no-load the capacitive current may flow due to overcapacity of the capacitor in line,
which causes the power loss of the line and transformer, and electric stress on motors. This element can be used to protect against such current.
Under Power Factor
The under power factor element operates if the power factor falls below the setting level.
If the power factor of a customer falls below that of a generator in a power plant the generator current increases over the rated current or the power
output is limited. For this reason, the power factor of a customer is regulated.
In addition, the under power factor causes the increase of the input current which prevents the temperature rise in cables, transformers and motors.
Voltage
&
Power Protection
80
Electronic Motor Protection Relays
Содержание EMPR DMPi Series
Страница 2: ...Electronic Motor Protection Relays ...
Страница 34: ...DMPi Series LSIS Co Ltd 33 MEMO ...
Страница 60: ...GMP Series LSIS Co Ltd 59 MEMO ...
Страница 72: ...IMP Series MEMO LSIS Co Ltd 71 ...
Страница 98: ...MMP Series MEMO LSIS Co Ltd 97 ...
Страница 107: ...106 Electronic Motor Protection Relays MEMO ...