Basler BE1-CDS240, Instruction Manual

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BESTlogic Expression Builder
The BESTlogic Expression Builder is used to connect the inputs of the relay's function blocks, physical
inputs and outputs, and virtual outputs. Using the BESTlogic Expression Builder is analogous to
physically attaching wire between discrete relay terminals. The BESTlogic Expression Builder is opened
each time the input of a BESTlogic function block is selected. Figure 7-7 illustrates the BESTlogic
Expression Builder screen.
Figure 7-7. BESTlogic Expression Builder Screen
The BESTlogic Expression Builder provides a point and click interface that allows the selected input to be
easily connected using a single OR gate, single AND gate, or an AND/OR combination. The usable list of
inputs and outputs in the bottom left of the screen corresponds with the variable lists of Table 7-1.
Currently, the virtual outputs are the only functions that can use the single AND or AND/OR combination
BESTlogic Expression Type .
The top of the screen displays the BESTlogic expression in a text window. Above the text window, the
selected input and the associated ASCII command are displayed.
The Clear button will clear the expression to 0. The Reset button will reset the expression to its original
state when the BESTlogic Expression Builder was first opened. The Cancel button resets the expression
to its original state when the BESTlogic Expression Builder was first opened and returns the user to the
previous screen. The Save button saves the expression shown in the text window and returns the user to
the previous window.
LOGIC SCHEMES
A logic scheme is a group of logic variables written in equation form that defines the operation of a
multifunction relay. Each logic scheme is given a unique name up to 16 characters in length (i.e.,
CDS240-BATX-A-BE). This allows the user to select a specific scheme and be confident that the selected
scheme is in operation. Several preprogrammed logic schemes are available, one embedded in the relay
firmware and several schemes that can be copied from the BESTCOMS logic library. Only one of these
logic schemes can be active at a given time. In most applications, preprogrammed logic schemes
eliminate the need for custom programming. Preprogrammed logic schemes may provide more inputs,
outputs, or features than are needed for a particular application. This is because the preprogrammed
schemes are designed for a large number of applications with no special programming required.
Unneeded inputs or outputs may be left open to disable a function. Or a function element can be disabled
through operating settings. Unused current sensing inputs should be shorted to minimize noise pickup.
7-10 BE1-CDS240 BESTlogic Programmable Logic 9365200990 Rev F