6. Function blocks
6.1 Manufacturer function blocks
Period duration to minimum ON duration ratio
The ratio of the period duration/minimum on duration (P/M) determines which per-
centage of manipulated variables have no effect.
The minimum on duration must be set as low as possible so that P/M is as high as pos-
sible.
If, however, a very short on duration has no effect on the connected actuator, it is advis-
able to suppress these short on phases in order to reduce the load on the hardware. In
this case, the period duration should not be set too low.
Assigning operands
You can assign the following operands to the function block inputs that are numeric
inputs.
Operands Value inputs
Constant, timer constant x
MD, MW, MB - Markers x
NB, NW, ND - NET markers x
nNB, nND, nND- NET markers
NET stations n
x
IA - Analog input x
QA - Analog output x
QV - QV - Numeric output of a FB x
You can assign the following operands to the function block inputs that are bit inputs:
Operands Bit inputs
Constant 0, constant 1 x
M – Markers x
RN - Input bit via NET x
SN - Output bit via NET (send) x
N - Net marker bit x
nN - NET marker bit NET station n x
ID: Diagnostic alarm x
LE - Output backlight x
P buttons x
I - Bit input x
Q - Bit output x
Q - Bit output of a FB x
Function block outputs
Description Note
(Bit)
E1 Error output
1: if the value is below the minimum on dur-
ation or minimum off duration.
The range limits are checked irrespective
of the edge change on the Boolean EN
input.
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easyE4 11/18 MN050009 EN www.eaton.com