Schweitzer Engineering SEL-387-0, Instruction Manual

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4.2
SEL-387-0, -5, -6 Relay Instruction Manual Date Code 20170601
Control Logic
Optoisolated Inputs
Optoisolated Inputs
Relay Word bits IN101 through IN106, and IN201 through IN208 (interface
board), follow the states of the optoisolated level-sensitive inputs having the
same names. To assert an input, apply rated control voltage to the appropriate
terminal pair. As noted in
Section 1: Introduction and Specifications and
Section 2: Installation , these inputs have a specific voltage range for operation
and a dropout voltage value below which the input will deassert. The inputs
are not polarity sensitive; either terminal can be positive, the other negative.
Input Functions
There are no optoisolated input settings such as
IN101 =
IN102 =
Optoisolated inputs receive their function by how their corresponding Relay
Word bits are used in SEL
OGIC
control equations. Remember that any input
Relay Word bit name will always appear on the right side of any SEL
OGIC
control equation, as shown below.
Factory Settings
Examples
Relay Word bit IN101 is used in the factory settings for the SEL
OGIC
control
equation circuit breaker status setting
52A1 = IN101
Connect input
IN101
to a 52a circuit breaker auxiliary contact for the Winding 1
breaker to provide the relay information on the position of the breaker
contacts.
If a 52b circuit breaker auxiliary contact were connected to input
IN101
, the
setting could be changed to
52A1 = !IN101 [!IN101 = NOT(IN101)]
Input
IN101
may also be used in other SEL
OGIC
control equations. Any
equation that requires information on the open or closed status of Breaker 1
would use the IN101 Relay Word bit as this indication.
Local Control Switches (All But SEL-387-0 Relay)
The local control switch feature of this relay replaces traditional panel-
mounted control switches. Operate the 16 local control switches using the
front-panel keyboard/display (see
Section 8: Front-Panel Interface ).