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CET Inc.
Notes:
1)
Bits 0 to 11 represent the
SM Current Alarm Enable
for SM1 to 12 respectively, with the bit value “0” meaning Disabled and
“1” meaning Enabled. For example, 0x003F means SM1 to 6 are enabled for
Current Alarm
and SM7 to 12 are disabled.
2)
0 means this Alarm Channel is disabled.
3)
0 means the Current Alarm Trigger is disabled.
For High and High-High Alarms, which are conceptually similar to Over Setpoint:
Return Threshold = Alarm Threshold x (1 – Universal Hysteresis)
For Low and Low-Low Alarms, which are conceptually similar to Under Setpoint:
Return Threshold = Alarm Threshold x (1 + Universal Hysteresis)
The following logic diagrams illustrates the different levels of Current Alarms.
Where
SMx Current Alarm Limit = SMx’s Breaker Rating x Alarm Threshold (%)
It should be noted that the absolute value of the Current Alarm Limit is calculated based on the Breaker
Rating parameters.
Therefore, it’s critical to set the Breaker Rating correctly for each SM Current for
the Current Alarms to work properly.
Current HH Alarm:
Figure 4-15 Current HH Alarm Logic Diagram
Current H Alarm:
Figure 4-16 Current H Alarm Logic Diagram