Continuous Monitoring Of The Measured Quantity; Continuous Supervision Of The Measured Quantity - ABB REC 561 User Manual

1MRK 580 154-XEN
Page 7 - 6

3 Continuous monitoring of the measured quantity

4 Continuous supervision of the measured quantity

Direct current measuring unit
User can this way select for each measuring quantity on each monitored
object of a power system the most suitable measuring range and this way
optimise a complete functionality together with the characteristics of the
used measuring transducer.
The user can continuously monitor the measured quantity in each channel
by means of six built-in operating limits, see Fig. 1. Two of them are
defined by the selection of operating range: I_Max as the upper and
I_Min as the lower operating limit. The other four operating limits oper-
ate in two different modes of operation:
• Overfunction, when the measured current exceeds the HiWarn or
HiAlarm pre-set values
• Underfunction, when the measured current decreases under the Low-
Warn or LowAlarm pre-set values
Y
RMAXAL=1
HIALARM=1
HIWARN=1
LOWWARN=1
LOWALARM=1
Fig. 1 Presentation of the operating range and operating limits
Each operating level has its corresponding functional output signal (FOS).
Its logical value changes according to Fig. 1.
You can set the hysteresis, which determines the difference between the
operating and reset value at each operating point, in wide range for each
measuring channel separately. The hysteresis is common for all operating
values within one channel.
The actual value of the measured quantity is available locally and
remotely. The measurement is continuous for each channel separately.
But the reporting of the value to the higher levels (control processor in the
module, MMI and SCS) depends on the selected reporting mode.
ABB Network Partner AB
RMAXAL=0
HIALARM=0
HIWARN=0
Hysteresis
LOWWARN=0
LOWALARM=0
RMINAL=0
RMINAL=1
Version 1.0-00
I_Max
HiAlarm
HiWarn
t
LowWarn
LowAlarm
I_Min
(X80154-1)