Basler BE1-CDS220, Инструкция по эксплуатации

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BE1-CDS220 BESTlogic Programmable Logic 7-9
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 by typing them into the appropriate text box on the
related BESTCOMS screen. All of the BE1-CDS220’s inputs, outputs, and 43 switches have labels that
can be edited. Table 7-2 shows the range and purpose of each label. Alternately, labels may be edited
using the SN-ASCII command.
Table 7-2. Programmable Variable Name Setting
Settings Range/Purpose Default
Name/Label
1 to 16 characters.
User name to replace <var> in the RS report.
INPUT_x
SWITCH_x43
VOx_LABEL
True/Energized State
1 to 7 characters.
Used to replace default labels.
TRUE
False/De-Energized State
1 to 7 characters.
Used to replace default labels.
FALSE
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 elements, 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.
OUT1 through OUT5 have normally open contacts (coil is de-energized). OUT6 is Form C and has one
normally open and one normally closed contact. Normally open contacts can be used as normally closed
outputs by inverting the logic expressions that drive them. Inverting an output logic expression causes the
coil to be energized with the contacts closed in the normal state. Caution should be taken with normally
closed contact logic because there are no shorting bars to maintain the closed condition if the draw-out
assembly is removed from the chassis. In applications where a normally closed output is needed even
when the electronics are removed, a normally open contact from the relay can be used to drive a low-cost
auxiliary relay. The normally closed output of the auxiliary relay will maintain the closed output when the
draw-out assembly is removed from the case. Alternately, an external switch can be used to short across
a normally closed relay output when the draw-out assembly is removed. Extra care is required to ensure
that the switch is closed prior to removing the draw-out assembly and that the switch is open after the
relay is placed back in service.
Several links between the programmable alarms function and BESTlogic programmable logic allow alarm
functions to be used in a logic scheme and programmable logic functions to be used in the alarm
reporting function.
Programmable alarm settings for Major, Minor, and Logic alarms drive BESTlogic variables ALMMAJ,
ALMMIN, and ALMLGC. These variables can be used in logic expressions to control logic when an alarm
is active.
Virtual outputs VO13, VO14, and VO15 are driven by BESTlogic expressions. These three logic variables
are also available in the programmable alarm function. Virtual outputs can also be assigned user
programmable labels (described previously). With this feature, a logic condition can be designed and
used for an alarm. The virtual output label would then be reported in the alarm reporting function.