Fuji Electric FRENIC-HVAC User Manual page 402

Enable data change with keypad -- WE-KP (Function code data = 19)

Turning the terminal command WE-KP OFF protects function code data from accidentally
getting changed by pressing the keys on the keypad.
Only when this terminal command is ON, you can change function code data from the
keypad.
 Refer to F00.
Cancel PID control -- Hz/PID (Function code data = 20)

Turning this terminal command ON disables PID control.
If the PID control is disabled with this command, the inverter runs the motor with the
reference frequency manually set by any of the multistep frequency, keypad, analog input,
etc.
Terminal command
Hz/PID
OFF
ON
 Refer to J101 through J131 and J201 through J231.
Switch normal/inverse operation -- IVS (Function code data = 21)

This terminal command switches the output frequency control between normal (proportional
to the input value) and inverse in analog frequency setting or under PID process control. To
select the inverse operation, turn the IVS ON.
The normal/inverse switching operation is useful for air-conditioners that require
switching between cooling and heating. In cooling, the speed of the fan motor
(output frequency of the inverter) is increased to lower the temperature. In heating,
it is reduced to lower the temperature. This switching is realized by the IVS.
• When the inverter is driven by an external analog frequency command sources
(terminals [12], [C1] and [V2]):
Switching normal/inverse operation can apply only to the analog frequency command
sources (terminals [12], [C1] and [V2]) in frequency command 1 (F01) and does not affect
frequency command 2 (C30) or UP/DOWN control.
As listed below, the combination of the "Selection of normal/inverse operation for frequency
command 1" (C53) and the terminal command IVS determines the final operation.
Combination of C53 and IVS
Data for C53
0: Normal operation
1: Inverse operation
Function
Enable PID control
Disable PID control/Enable manual settings
IVS
OFF
ON
OFF
ON
6-92
Final operation
Normal
Inverse
Inverse
Normal