Operation 1 (Inom)
30000 Op
Current 2 (Imax)
16.00 kA
Operations 2 (Imax)
100 Op
Enable Alarm 1
1: Enabled
Alarm 1 Set
1000 operations
Enable Alarm 2
1: Enabled
Alarm 2 Set
100 operations
With these settings Alarm 1 will be issued when any of the three phases cumulative interruptions
counter is below the set 1000 operations left and similarly when any of the counters is below the set
100 operations left Alarm 2 will be issued.
Events and registers
The CBW function generates events and registers from the status changes of Retrip, CBW activated
and blocked signals as well as from the internal pick-up comparators. To main event buffer is possible
to select status “On” or “Off” messages.
Function includes 12 last registers where the triggering event of the function is recorded with time
stamp and process data values.
Table. 5.6.5. - 221. Event codes of the CBW function instance
Event Number
Event channel
Event block name
Event Code
Description
3712
58
CBW1
0
CBWEAR1 Triggered
3713
58
CBW1
1
CBWEAR1 Alarm1 On
3714
58
CBW1
2
CBWEAR1 Alarm1 Off
3715
58
CBW1
3
CBWEAR1 Alarm2 On
3716
58
CBW1
4
CBWEAR1 Alarm2 Off
In the register of the CBW function recorded events are activated “On” event process data. In the table
below is presented the structure of CBW function register content. This information is available in 12
last recorded events for all provided instances separately.
Table. 5.6.5. - 222. Register content.
Date & Time
Event
code
Trigger current
All.Op.ITrg
Deduct. Op
Op.Left
dd.mm.yyyy
hh:mm:ss.mss
3713-3717
Descr.
Phase currents on
trigger time
Allowed operations with
trigger current
Deducted operations from
the cumulative sum
Operations
left
5.6.6. Total harmonic distortion monitor (THD)
Total harmonic distortion monitor function (THD) is used for monitoring the current harmonic content.
THD is a measurement of the harmonic distortion present and is de ned as the ratio of the sum of
powers of all harmonic components to the power of fundamental frequency.
Harmonics can be caused by different sources in the electric networks like electric machine drives,
thyristor controls etc. Monitoring of the THD of the currents can be used to alarm in case if the
harmonic content rises too high in cases if either the electric quality requirement exist in the protected
unit or in cases if process generated harmonics needs to be monitored.
AQ-T257
Instruction manual
Version: 2.00
© Arcteq Relays Ltd
282