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Functions
3.3 Limit violation Alarm
SICAM P27, 3-phase Harmonic Power Meter, User Manual
E50417-H8940-C560-
, Release Date
16
3.3
Limit violation Alarm
1. This product is provided with limit violation alarm function. User may select from voltage, current, power,
power factor and frequency parameters up to 6 data groups at the same time as detection object and set
upper and lower limits and judgment condition for them. Alarm will be activated when measured value is over
the set limit. This product is provided with 2 relay outputs. When alarm parameters are configured that output
is made from certain relay which is at automatic mode (not manual), limit violation alarm signal can be output
through such relay (relay closing).
2. Up to 6 limit violation alarm parameters can be set at the same time within the product. Configuration flow of
each limit violation alarm parameter: select type of detected data-set threshold of detected data-set judgment
condition-select output relay for alarm signal.
• Code of various detected data: (hexadecimal number for Modbus-RTU code)
When code of detected data is FF, limit violation alarm function of such group is off.
• Threshold of detected data: threshold judging whether detected value is out of limit; Different units for
different data types: such as voltage-V, current-A, active-KW, reactive power-KVAR, apparent-KVA,
frequency-Hz.
• Judging condition: 0 means alarm activated when exceeding limit; 1 means alarm activated when falling
below limit.
• Alarm signal output relay: 0 means no alarm signal output; 1 means alarm signal outputted from relay 1.
3. Example of alarm parameter setting. Set one limit violation alarm parameter to automatic detection and alarm
for "Phase A voltage", assuming that alarm threshold is 240 V, judging criterion is "over limit) and signal is
outputted from relay 2.
Use MODBUS RTU protocol to set alarm parameter: set 0110 address to "07", 0111 to "0000", 0112 to
"5DC0" (multiply "240" by 100 to generate "24,000" and convert it into "00005DC0"), 0113 to "00" and 0114
to "02".
MODBUS code
Content of data
MODBUS code
Content of data
00
Phase A power factor
14
Phase A active power
01
Phase B power factor
15
Phase B active power
02
Phase C power factor
16
Phase C active power
03
Total power factor
17
Total active power
06
Frequency
18
Phase A reactive power
07
Phase A voltage
19
Phase B reactive power
08
Phase B voltage
1A
Phase C reactive power
09
Phase C voltage
1B
Total reactive power
0B
Uab line voltage
1C
Phase A apparent power
0C
Ubc line voltage
1D
Phase B apparent power
0D
Uca line voltage
1E
Phase C apparent power
0F
Phase A current
1F
Total apparent power
10
Phase B current
11
Phase C current
12
Neutral current