of the value to the phase selection logic. If the ENA_MULT input is active, the
Start
value
setting is multiplied by the
Start value Mult
setting.
The protection relay does not accept the
Start value
or
Start value Mult
setting if the product of these settings exceeds the
Start value
setting
range.
The start value multiplication is normally done when the inrush detection function
(INRPHAR) is connected to the ENA_MULT input.
Figure 122: Start value behavior with ENA_MULT input activated
Phase selection logic
If the fault criteria are fulfilled in the level detector and the directional calculation,
the phase selection logic detects the phase or phases in which the measured
current exceeds the setting. If the phase information matches the
Num of start
phases
setting, the phase selection logic activates the timer module.
Timer
Once activated, the timer activates the START output. Depending on the value of the
Operating curve type
setting, the time characteristics are according to DT or IDMT.
When the operation timer has reached the value of
Operate delay time
in the DT
mode or the maximum value defined by the inverse time curve, the OPERATE output
is activated.
When the user-programmable IDMT curve is selected, the operation time
characteristics are defined by the parameters
Curve parameter A
,
Curve parameter
B
,
Curve parameter C
,
Curve parameter D
and Curve parameter E.
Protection functions
1MRS758755 C
240 REC615 & RER615
Technical Manual
To Next Page
Loading...
