BESTlogic Programmable Logic
BE1-951
7-10
“Settings Record” spreadsheet is available with the BE1-951 and contains all of the preprogrammed logic
schemes. These schemes can be modified and saved as a text file and then uploaded to the relay’s active
logic. See Appendix C,
Relay Setting Record for more information.
Debugging the Logic Scheme
If there are problems with a customized logic scheme, the RG-STAT command can be used to check the
status of all logic variables. More information about the RG-STAT command can be found in Section 6,
Reporting and Alarm Functions.
USER INPUT AND OUTPUT LOGIC VARIABLE NAMES
Assigning meaningful names to the inputs and outputs makes sequential events reports easier to analyze.
Input and output logic variable names are assigned with the SN command. All SN labels are used in the RS
(reports, sequence of events) reports. Entering SN by itself returns a list of all programmable names.
Table 7-2. Programmable Variable Name Setting
Settings
Range/Purpose
Default
name
1 to 10 Characters.
User name to replace <var> in the RS report
N/A
TRUE label
1 to 7 Characters.
Used to replace default labels
TRUE
FALSE label
1 to 7 Characters.
Used to replace default labels
FALSE
SN Command
Purpose:
Read or set user-programmable names.
Syntax:
SN[-<var>[=<name>,<TRUE label>,<FALSE label>]
Comments: var = logic variable 43/143/243/343, VOA, VO1 - VO15, or IN1 - IN4
name = 1 to 10 character user name to replace <var> in the RS report
TRUE label = 1 to 7 character user label to replace default TRUE label for <var>
FALSE label = 1 to 7 character user label to replace default FALSE label for <var>
SN Command Examples
1.
Read the current name setting for IN1.
>SN-IN1
SN-IN1=IN1,CLOSED,OPEN
2.
Change the name for IN1 to better describe its function as a 52b contact.
>SN-IN1=BREAKER,OPEN,CLOSED
3.
Label the 43 switch operation for use on the HMI.
>SN-43=AUTO_SG,DISABLE,ENABLE
BESTlogic APPLICATION TIPS
When designing a completely new logic scheme, logic evaluation order should be considered. Contact
sensing inputs are evaluated first, then the function blocks, and then the virtual outputs. VO15 is evaluated
first and VOA is evaluated last. If a virtual output is used in a logic expression to control another virtual
output, the virtual output used in the expression should be numerically higher. Otherwise, a logic expression
for a numerically smaller virtual output won’t be available to a numerically higher virtual output until the next
processing interval. Logic is evaluated every quarter-cycle.
When designing custom protection schemes, avoid confusion by maintaining consistency between input and
output functions in the custom scheme and the preprogrammed schemes.
