Symbols Used In Block Diagrams And Their Meanings - Fuji Electric FRENIC-HVAC User Manual

FRENIC-HVAC series of inverters is equipped with a number of function codes to match a variety of motor
operations required in your system. Refer to Chapter 6 "FUNCTION CODES" for details of the function
codes.
The function codes have functional relationship each other. Several special function codes also work with
execution priority each other depending on their functions or data settings.
This chapter explains the main block diagrams for control logic in the inverter. You are requested to fully
understand the inverter's control logic together with the function codes in order to set the function code data
correctly.
The block diagrams contained in this chapter show only function codes having mutual relationship. For the
function codes that work independently and for detailed explanation of each function code, refer to Chapter 6
"FUNCTION CODES."

7.1 Symbols Used in Block Diagrams and their Meanings

Table 7.1 lists symbols commonly used in block diagrams and their meanings with some examples.
Symbol
Programmable, digital
[FWD], [Y1] inputs/outputs to/from the
etc. inverter's control circuit
terminal block.
Control signals (input) or
FWD, REV
status signals (output),
etc. assigned to control circuit
terminals.
Low-pass filter: Features
appropriate characteristics
by changing the time
constant through the
function code data.
Internal control signal for
inverter logic.
High limiter: Limits the
upper value by a constant or
data set to a function code.
Low limiter: Limits the
lower value by a constant or
data set to a function code.
Zero limiter: Prevents data
from dropping to a negative
value.
Gain multiplier for reference
frequencies given by current
and/or voltage input or for
analog output signals.
C = A × B
Adder for 2 signals or
values. C = A + B
If B is negative then C = A –
B (acting as a subtracter).
7.1 Symbols Used in the Block Diagrams and their Meanings
Table 7.1 Symbols and Meanings
Meaning
7-1
Symbol Meaning
Function code.
Switch controlled by a
function code. Numbers
assigned to the terminals
express the function code
data.
Switch controlled by a
terminal command. In the
example shown on the left,
the enable communications
link command LE assigned
to one of the digital input
terminals from [X1] to [X7]
controls the switch.
OR logic: In normal logic, if
any input is ON, then C =
ON. Only if all inputs are
OFF, then C = OFF.
NOR (Not-OR) logic: In
normal logic, if any input is
OFF, then C = ON. If all
inputs are ON, C = OFF.
AND logic: In normal logic,
only if A = ON and B = ON,
then C = ON. Otherwise, C =
OFF.
NOT logic: In normal logic,
if A = ON, then B = OFF, and
vice versa.