Mitsubishi Electric 800 Series Instruction Manual page 425

5.11.9 PID pre-charge function
This function drives the motor at a certain speed before starting PID control. This function is useful for a pump with a long hose.
Without this function, PID control would start before the pump is filled with water, and proper control would not be performed.
Pr.
760 Pre-charge fault selection
A616
761 Pre-charge ending level
A617
762 Pre-charge ending time
A618
763 Pre-charge upper detection
A619 level
764 Pre-charge time limit
A620
1132 Pre-charge change
A626 increment amount
765 Second pre-charge fault
A656 selection
766 Second pre-charge ending
A657 level
767 Second pre-charge ending
A658 time
768 Second pre-charge upper
A659 detection level
769 Second pre-charge time limit 9999
A660
1133 Second pre-charge change
A666 increment amount
 Operation selection for the pre-charge function
• To enable the pre-charge function when PID control is enabled, set the pre-charge end conditions at Pr.761 Pre-charge
ending level and at Pr.762 Pre-charge ending time, or set "77" to Pr.178 to Pr.189 (Input terminal function selection).
When operation is started, the inverter runs at the frequency set to Pr.127 PID control automatic switchover frequency
to enter the pre-charge state.
• Pre-charge ends and PID control starts after a pre-charge ending condition is satisfied.
• The pre-charge function is also activated at a start after release of a PID output suspension (SLEEP) state or MRS (output
shutoff). The PID output suspension (SLEEP) function is not activated until the started pre-charge operation ends.
• During pre-charge operation, the During pre-charge operation (Y49) signal is output. For the terminal used for Y49 signal
output, set "49 (positive logic)" or "149 (negative logic)" in any of Pr.190 to Pr.196 (Output terminal function selection)
to assign the function.
424
5. PARAMETERS
5.11 (A) Application parameters
Name Initial
value
0
9999
9999
9999
9999
9999
0
9999
9999
9999
9999
Setting range
0 Fault indication with output shutoff immediately after pre-charge
fault occurs.
1 Fault indication with deceleration stop after pre-charge fault
occurs.
0 to 100% Set the measured amount to end the pre-charge operation.
9999 Without pre-charge ending level
0 to 3600 s Set the time to end the pre-charge operation.
9999 Without pre-charge ending time
0 to 100% Set the upper limit for the pre-charged amount. A pre-charge
fault occurs when the measured value exceeds the setting
during pre-charging.
9999 Without pre-charge upper limit level
0 to 3600 s Set the time limit for the pre-charged amount. A pre-charge fault
occurs when the pre-charge time exceeds the setting.
9999 Without pre-charge time limit
0 to 100% Set the change increment amount per second after the
automatic switchover frequency is reached (for vertical pumps).
9999 Constant-speed operation after the automatic switchover
frequency is reached (for horizontal pumps).
0, 1 Refer to Pr.760.
0 to 100%, Refer to Pr.761.
9999
0 to 3600 s, Refer to Pr.762.
9999
0 to 100%, Refer to Pr.763.
9999
0 to 3600 s, Refer to Pr.764.
9999
0 to 100%, Refer to Pr.1132.
9999
Description
Set the second pre-charge function.
The second pre-charge function is
valid when the RT signal is ON.