Deadband Supervision - ABB RELION 620 Series Technical Manual

1MRS757644 F
3.13.2.8
620 series
Technical Manual
The range information of "High-high limit" and "Low-low limit" is combined from all
measurement channels to the Boolean ALARM output. The range information of
"High limit" and "Low limit" is combined from all measurement channels to the
Boolean WARNING output.
Table 54: Settings for RTD analog input limit value supervision
Function
RTD analog input
When the measured value exceeds either the Value maximum setting or the Value
minimum setting, the corresponding quality is set to out of range and a maximum or
minimum value is shown when the measured value exceeds the added hysteresis,
respectively. The hysteresis is added to the extreme value of the range limit to allow
the measurement slightly to exceed the limit value before it is considered out of range.

Deadband supervision

Each input has an independent deadband supervision. The deadband supervision
function reports the measured value according to integrated changes over a time
period.
GUID-63CA9A0F-24D8-4BA8-A667-88632DF53284 V1 EN
Figure 36: Integral deadband supervision
The deadband value used in the integral calculation is configured with the Value
deadband setting. The value represents the percentage of the difference between the
maximum and minimum limits in the units of 0.001 percent * seconds. The reporting
delay of the integral algorithms in seconds is calculated with the formula:
Settings for limit value supervision
Out of range Value maximum
High-high limit Val high high limit
High limit Val high limit
Low limit Val low limit
Low-low limit Val low low limit
Out of range Value minimum
Section 3
Basic functions
117