Mitsubishi Electric 800 Series Instruction Manual page 431

 Multi-pump function control method
• Use Pr.579 Motor connection function selection to select the control method for the multi-pump function. Use Pr.578
Auxiliary motor operation selection to set the number of auxiliary motors.
Pr.579 setting Control method
0 Basic system
1 Alternative
system
2 Direct system
3 Alternative direct
system
Flow rateQ
Pr. 579 = 0
Motor 1 (M1)
Motor 2 (M2)
Motor 3 (M3)
Motor 4 (M4)
Pr. 579 = 1
Motor 1 (M1)
Motor 2 (M2)
Motor 3 (M3)
Motor 4 (M4)
Pr. 579 = 2
Motor 1 (M1)
Motor 2 (M2)
Motor 3 (M3)
Motor 4 (M4)
Pr. 579 = 3
Motor 1 (M1)
Motor 2 (M2)
Motor 3 (M3)
Motor 4 (M4)
The starting order of motors is M2  M3  M1 if the previous order was M1  M2  M3.
*1
*2 The motor starts in the order of elapsed time after completion of the previous inverter-driven operation, from the longest to the shortest. (The
motor that has not been driven by the inverter for the longest time starts first.)
430
5. PARAMETERS
5.11 (A) Application parameters
The motor driven by the inverter is always fixed. Commercial power supply operation of auxiliary
motors is available by turning on and off the MC between the power supply and the motor depending
on the output frequency of the inverter.
The motor driven by the inverter is fixed during operation. Commercial power supply operation of
auxiliary motors is available by turning on and off the MC between the power supply and the motor
depending on the output frequency of the inverter.
When output is shut off by the SLEEP function, the MC between the inverter and the motor is
switched to switch the motor to be driven by the inverter.
When the start signal is turned ON, the motor is started by the inverter. When the conditions to start
the next motor are established, MCs between the inverter and the motor and the power supply and
the motor are switched to change the operation of the motor driven by the inverter to commercial
power supply operation, and the next motor is started by the inverter.
When conditions to stop motors are established while auxiliary motors are running, the motor started
first (currently driven by the commercial power supply) is stopped first, and then the other motors are
stopped.
When the start signal is turned ON, the motor is started by the inverter. When the conditions to start
the next motor are established, MCs between the inverter and the motor and the power supply and
the motor are switched to change the operation of the motor driven by the inverter to commercial
power supply operation, and the next motor is started by the inverter.
When conditions to stop motors are established while auxiliary motors are running, the motor driven
by the inverter is decelerated to stop, and operation of a motor currently driven by the commercial
power supply is switched to the inverter-driven operation after frequency search. To perform
frequency search when the motor operation is switched from commercial power supply operation to
inverter-driven operation, set Pr.57 Restart coasting time ≠ "9999".
Qmax
Q3
Q2
Q1
∗1
∗2
Description
Time
∗1
∗2
Driven
by inverter
Driven by
commercial
power supply
Stop