Bestlogic application hints, Bestlogic application hints -9 – Basler Electric BE1-BPR User Manual

Page 115

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9272000990 Rev J

BE1-BPR BESTlogic Programmable Logic

5-9

LI

Contact input logic

HMI Menu Branch: N/A

Parameter

Unit of Measure

Range

Increment

Default

#

N/A

1, 2, 3, 4, 5, 6, or 7

N/A

LI#=4,12

r

milliseconds

4 - 255

1

db

milliseconds

4 - 255

1


LI Command
Purpose:

Reads or programs contact input logic.

Syntax:

LI[#[=<r>,<db>]]

Comments:

Access area one password is required to change settings.


LI Command Example:
Configure input 3 for a contact recognition time of 10 milliseconds and a debounce time of 20

milliseconds.

LI3=10,20


The state of the contact sensing inputs is scanned twelve times per cycle. The time settings are converted

to the nearest multiple of the scan interval, which is determined by the nominal frequency setting (1.39

milliseconds at 60 hertz or 1.67 milliseconds at 50 hertz). For example, if the nominal frequency is 60

hertz, a recognition time setting of 4 milliseconds is rounded to 4.17 milliseconds, which is the nearest

multiple of the scan interval. In this case, a contact closure must be present on three consecutive scans of

the input state for it to be recognized and the BESTlogic input variable to change state from a 0 to 1.

BESTLOGIC APPLICATION HINTS

Preprogrammed protection schemes may provide additional inputs, outputs, or features that are not

needed for all applications. This is done so that a few schemes can be used in a large number of

applications with no special programming required. The unneeded inputs or outputs may be left open to

disable the function. Unused CT inputs should be shorted to minimize noise pickup.
Additional Breaker Failure inputs have been provided in many schemes for diagnostic reasons. Target

information can be provided for inputs as well as outputs, therefore the relay that caused the breaker

operation may be identified by requesting target information through the communications port. This is

especially useful when trying to remotely determine the cause of a problem when the relay that tripped

the breaker is an older, non-communicating relay.
When designing new protection schemes, avoid unnecessary confusion by maintaining consistency

wherever possible between function of the inputs and outputs in the new scheme and the preprogrammed

schemes. The preprogrammed schemes are consistent in the following functions:

IN1 (I1) = Breaker status contact (isolated input)

IN3 (I3) = Primary BFI (isolated input)

IN7 (I7) = External fault trigger to record fault records on enhanced relays

F1 = Always associated with phase fault detector

F2 = Always associated with neutral fault detector

ALM (OA) = Alarm output

OUT1 (O1) = Primary BFO - high speed (1/4 cycle pickup)

OUT2 (O2) = Secondary BFO

OUT3 (O5) = Retrip Output

TIMER1 (T1) = Always associated with primary BFO delay timer

TIMER2 (T2) = Always associated with alternate BFO delay timer

TIMER3 (T3) = Always associated with the control timer

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