Continuous monitoring of the measured quantity
Users can continuously monitor the measured quantity available in each function
block by means of four defined operating thresholds, see figure 417. The monitoring
has two different modes of operating:
• Overfunction, when the measured current exceeds the High limit (XHiLim) or
High-high limit (XHiHiLim) pre-set values
• Underfunction, when the measured current decreases under the Low limit
(XLowLim) or Low-low limit (XLowLowLim) pre-set values.
X_RANGE is illustrated in figure
417.
IEC05000657-2-en.vsdx
X_RANGE= 1
X_RANGE = 3
X_RANGE=0
Hysteresis
High-high limit
High limit
Low limit
Low-low limit
X_RANGE=2
X_RANGE=4
Y
t
X_RANGE=0
IEC05000657 V2 EN
Figure 417: Presentation of operating limits
Each analogue output has one corresponding supervision level output (X_RANGE).
The output signal is an integer in the interval 0-4 (0: Normal, 1: High limit exceeded,
3: High-high limit exceeded, 2: below Low limit and 4: below Low-low limit). The
output may be connected to a measurement expander block (XP (RANGE_XP)) to get
measurement supervision as binary signals.
The logical value of the functional output signals changes according to figure
417.
The user can set the hysteresis (XLimHyst), 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.
Actual value of the measured quantity
The actual value of the measured quantity is available locally and remotely. The
measurement is continuous for each measured quantity separately, but the reporting
1MRK502052-UEN B Section 16
Monitoring
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Technical manual