Watlow LogicPro - Manual (Page 167)

LogicPro User’s Guide Chapter 10: Function Blocks
Doc.# 28002-00 Rev 3.00 Watlow Anafaze 151
Real Multiply (RMUL)
The Real Multiply (RMUL) function block, shown in Figure
10.31, produces the product of two values.
RMUL calculates the product between one value (RA) and
another value (RB) and places the result in another Variable
(RC) when the enable bit (EN) is True. The values of RA and
RB can be preset to a constant or assigned a Variable name,
which allows their value to change dynamically within the
program.
Figure 10.31 Real Multiply Function Block
Inputs
EN is the Real Multiply enable bit. A True condition of this bit
causes the values of RA and RB to be multiplied and the result
stored in RC. In a program using Ladder logic, the value of EN
is determined by the Boolean evaluation of elements placed
between the left power rail and EN in the function block. In
FBD programs, the value of EN is determined by the Variable
connected to EN. If no contacts are placed on the rung before
EN in a Ladder Diagram program, the value of EN is always
True. In FBD, all inputs must be connected to a Variable.
RA is a multiply value. The range of values this Variable can
assume is from -3.4x10
38 to 3.4x10 38 . If this Variable is
assigned a value out of these ranges, unpredictable results will
occur.
RB is another multiply value. The range of values this
Variable can assume is from -3.4x10
38 to 3.4x10 38 . If this
Variable is assigned a value out of these ranges, unpredictable
results will occur.
Outputs
ENO is the Real Multiply enable out bit. This bit is enabled and
passes power when the enable bit is True, as long as the value
of RC does not go out of range. Place an output coil on the
rung between Q in the function block and the right power rail
in a Ladder Diagram program.