ERL L-PRO 4000, User Manual

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Appendix A IED Specifications
D02706R02.30 L-PRO 4000 User Manual Appendix A-11
A.3 External Input Pickup Filter
To guarantee security from spurious voltage pulses an external input pickup
filter setting has been introduced. This setting is made in Relay Control Panel
under,
Utilities>Setup>External Inputs . The setting is an integer number rep-
resenting the number of samples in a packet of 12 that must be recognized by
the DSP as high before an External Input status is changed from low to high.
This will affect the pulse width required for the External Inputs to be detected.
Below is a table describing the pulse widths for possible and definite defection
for each setting.
For a setting of 6, it will take between 1.042 and 1.909 ms for an External Input
to be declared as high. The default setting is 4.
Pickup Filter
Count Input Pulse Width required for
EI to be possibly detected
Input Pulse Width required
for EI to be definitely
detected
4 0.694 ms 1.215 ms
5 0.868 ms 1.563 ms
6 1.042 ms 1.909 ms
7 1.215 ms 2.257 ms
8 1.389 ms 2.604 ms
9 1.563 ms 2.951 ms
10 1.736 ms 3.299 ms
11 1.909 ms 3.645 ms
12 2.083 ms 3.993 ms