Mitsubishi Electric FR-F820-00046 Instruction Manual page 45

PID input pressure control (Pr.1370, Pr.1373, and Pr.1377 to
Pr.1381)
• This function controls the pump inlet pressure to prevent water shortage that may cause air intake or cavitation on
the pump.
• To enable the PID input pressure control function, set the terminal for the pressure input in Pr.1377 PID input
pressure selection.
Pr.1377 setting
1 Terminal 1
2 Terminal 2
3 Terminal 4
The PID input pressure control
9999 (Initial value)
function is disabled.
• When the input pressure measured at the inlet remains lower than the Pr.1378 PID input pressure warning
level for the time set in Pr.1370 Detection time for PID limiting operation, the PID input pressure warning
signal (Y229) is output. Also, the set point is changed by the amount set in Pr.1380 PID input pressure warning
set point change amount.
• Set the rate (%/s) for changing the set point by the Pr.1380 setting value in Pr.1373 PID measured value control
set point change rate. When the input pressure falls within the normal range, the set point returns to its original
value.
• When the input pressure measured at the inlet remains lower than the Pr.1379 PID input pressure fault level for
the time set in Pr.1370 Detection time for PID limiting operation, the operation for the abnormal input pressure
starts and the PID input pressure fault signal (Y230) is output.
• Select the operation for the abnormal input pressure in Pr.1381.
Pr.1381 setting
Output shutoff by the protective function (E.PID)
0 (Initial value)
activation
Deceleration stop (Operation can be restarted when the
1
input pressure returns to normal.)
• For the Y229 and Y230 signals, assign the functions to output terminals using the Pr.190 to Pr.196 (output
terminal function selection).
Output signal
Positive logic
Y229 229
Y230 230
• To monitor the input pressure, set "69" in the monitor selection parameters. (0.1% increments)
Monitor type
PID input pressure
value
Pressure input terminal
Operation for the abnormal input pressure
Pr.190 to Pr.196 setting
Negative logic
329
330
Parameter setting
Pr.52, Pr.774 to
Pr.776, and Pr.992
(Terminal FM/CA
(Operation panel
indication)
69 69
Set Pr.868="0 (initial value)".
―
Set Pr.858="0 (initial value)".
―
Pr.54 Pr.158
(Terminal AM
output) output)
69
11
Remarks
Y230 signal
The signal is output at the same
time with the protective function.
The signal is output after a
deceleration stop.
Communication monitor code
RS-485
communication
dedicated monitor
(hexadecimal)
H45
BCN-C22005-703
MODBUS RTU
real time
monitor
40269