BE1-951
Protection and Control
4-3
Selection of the active setting group provided by this function logic can also be overridden. When logic
override is used, a setting group is made active and the BE1-951 stays in that group regardless of the state
of the manual logic control conditions.
Setting BESTlogic Settings, Setting Group Control Function Logic
The logic settings for the setting group control functions are provided in Table 4-2. These settings determine
how the function selects the active setting group when manual (logic) is enabled.
Table 4-2. Setting Group Control Functions BESTlogic Settings
Function
Range/Purpose
Default
Logic Mode
0=Disabled, 1=Discrete Input Selection,
2=Binary Coded Selection
(If auto mode is desired, logic mode must
be either 1 or 2.)
1
Discrete Input 0 (D0 Logic) Input
Logic expression.
Meaning depends upon the Mode setting.
0
Discrete Input 1 (D1 Logic) Input
Discrete Input 2 (D2 Logic) Input
Discrete Input 3 (D3 Logic) Input
Auto/Manual (Autologic) Input
Logic expression.
When TRUE, automatic control is
enabled. When FALSE, logic control is
enabled.
/0
The BESTlogic settings can be made from the ASCII command interface using the SL-GROUP (settings
logic-group control) command.
SL-GROUP Command
Purpose:
Read/Set Logic for Setting Group Module
Syntax :
SL-GROUP[=<Logic Mode>,<D0 logic>,<D1 logic>,<D2 logic>,<D3 logic>,<Autologic>]
Comments:
See Table 4-2 for SL-GROUP settings information
SL-GROUP Command Example
1.
Set the setting group control such that automatic selection is overridden and emergency overload
settings (SG3) are in place when Transformer 2 is out of service. Contact sensing input 2 is TRUE when
either the high side or low side breakers for Transformer 2 are open.
>SL-GROUP=1,0,0,0,IN2,/IN2
or
>SL-GROUP=2,IN2,IN2,0,0,/IN2
Manual (logic) control reads the status of the logic inputs to the setting group control function block to
determine what setting group should be active. For the logic inputs to determine which setting group should
be active, the AUTO input must be a logic 0. The function block logic mode setting determines how it reads
these logic inputs. There are three possible logic modes as shown in Table 4-1.
When the setting group control function block is enabled for Mode 1, there is a direct correspondence
between each discrete logic input and the setting group that will be selected. That is, asserting input D0
selects SG0, asserting input D1 selects SG1, etc. The active setting group latches in after the input is read
so they can be pulsed. It is not necessary that the input be maintained. If one or more inputs are asserted
at the same time, the numerically higher setting group will be activated. A pulse must be present for
approximately one second for the setting group change to occur. After a setting group change occurs, no
setting group change can occur within two times the SGC alarm-on time. Any pulses to the inputs will be
ignored during that period.
