Himoinsa CEM7 User Manual

CEA7 CONTROL UNIT ALARMS | PAGE 37
MAXIMUM GENSET FREQUENCY
The CEA7 control unit's maximum genset frequency alarm is associated with the
condition that the frequency generated by the genset is above the maximum
frequency limit set (Thresholds table, parameter 5).
The measurement of genset frequency is carried out on the rst phase. If in that
phase no signal is detected, the frequency measurement is then carried out on
the second phase. Likewise, if in that phase no signal is detected either, the
frequency measurement is then carried out on the third phase.
Detection of the maximum genset frequency alarm is set by default (Alarms
table, parameter 37) to be activated under nominal engine conditions.
A maximum genset frequency alarm can be associated a debounce time (Alarms
table, parameter 38) during which the frequency must be kept above the
maximum threshold limit set (Thresholds table, parameter 5).
The maximum genset frequency alarm is set by default (Alarms table, parameter
39) to perform an immediate stop of the engine.
INCORRECT GENSET PHASES SEQUENCE
The CEA7 control unit’s incorrect genset phases sequence alarm is associated
to the fact that the genset voltage inputs of each phase are in order (phases 123
for direct conguration of sequences —value 0, Regulations table, parameter
34— or phases 321 for inverse conguration of sequences —value 1,
Regulations table, parameter 34—).
The incorrect genset phases sequence alarm is only enabled when the control
unit is congured to work three-phase with neutral or three-phase without neutral.
Detection of the incorrect genset phases sequence alarm is set by default
(Alarms table, parameter 40) to be activated: Under nominal engine conditions.
An incorrect genset phases sequence alarm can be associated a debounce time
(Alarms table, parameter 41) during which an incorrect order in the maximum
genset voltages must be detected.
The incorrect genset phases sequence alarm is set by default (Alarms table,
parameter 42) to always perform a stop of the engine with cooling.
GENSET VOLTAGE ASYMMETRY
The CEA7 control unit's genset voltage asymmetry alarm is associated with the
condition that the difference between the measurements of RMS voltage in three-
phase gensets is above the maximum asymmetry limit set (Thresholds table,
parameter 4). The voltage asymmetry alarm is activated only when the control
unit is congured for voltage measurements of three-phase with neutral or three-
phase without neutral. Detection of the genset voltage asymmetry alarm is set by
default (Alarms table, parameter 31) to be activated under nominal engine
conditions.
The voltage asymmetry alarm can be associated a rebounce time (Alarms table,
parameter 32) during which the difference between any two values of genset
phase voltage (VG12, VG23 or VG31) should be kept above the maximum limit
set (Thresholds table, parameter 4). The genset voltage asymmetry alarm is set
by default (Alarms table, parameter 33) to always perform a stop of the engine
with cooling.
MAXIMUM GENSET VOLTAGE
The CEA7 control unit's maximum genset voltage alarm is associated with the
condition that the measurement of the genset's RMS voltage is above the
maximum voltage limit set (Thresholds table, parameter 2).
The phases which are evaluated for the detection of the maximum genset voltage
alarm are selected depending on the conguration of the installation phases
(Thresholds table, parameter 1):
• In a single phase conguration voltage V1N is tested.
• In a two-phase conguration voltage V12 is tested.
• In a two-phase selector conguration phases 1 and 3 are tested.
• In a three-phase conguration with neutral or three-phase without
neutral, phases V12, V23 and V13 are tested.
Detection of the maximum genset voltage alarm is set by default (Alarms table,
parameter 34) to be activated under nominal engine conditions. A maximum
genset voltage alarm can be associated a debounce time (Alarms table,
parameter 35) during which the RMS voltage must be kept above the maximum
threshold limit set (Thresholds table, parameter 2).
The maximum genset voltage alarm is set by default (Alarms table, parameter
36) to perform an immediate stop of the engine.

Himoinsa CEM7 Specifications

General

Brand	Himoinsa
Model	CEM7
Category	Control Unit
Language	English