ABB REC 561, User Manual, Page: 526 / 643

Direct current measuring unit
ABB Network Partner AB
1MRK 580 154-XEN
Page 7 - 7
Version 1.0-00
These reporting modes are available:
• Periodic reporting
• Periodic reporting with dead-band supervision in parallel
• Periodic reporting with dead-band supervision in series
Users can select between two types of dead-band supervision:
• Amplitude dead-band supervision(ADBS)
• Integrating dead-band supervision (IDBS)
4.1 Amplitude dead-band
supervision
If the changed value—compared to the last reported value—is larger than
the ±
∆
Y predefinied limits that are set by users, and if this is detected by
a new measuring sample, then the measuring channel reports the new
value to a higher level (Fig. 2). This limits the information flow to a mini-
mum necessary.
Fig. 2 Amplitude dead-band supervision
After the new value is reported, the new +
∆
Y limits for dead-band are
automatically set around it. The new value is reported only if the meas-
ured quantity changes more than defined by the new +
∆
Y set limits.
4.2 Integrating dead-band
supervision
The value of the measured quantity is updated even if the changes do not
exceed the amplitude dead-band supervision limits. The measured value is
updated if the time integral of all changes exceeds the pre-set limits, see
Fig. 3. The shadowed areas represent the time integrals which exceed the
pre-set value of the integrating dead-band supervision.
The last value reported (Y1 in Fig. 3) serves as a basic value for further
measurement. A difference is calculated between the last reported and the
newly measured value during the new sample and is multiplied by the
1 2 3 4 5 6
Y
t
∆
Y
∆
Y
∆
Y
∆
Y
Y1
Y2
Y3
new values reported
(x80154-2)