# Speed Display And Rotations Per Minute Setting - Mitsubishi Electric FR-A820-00046 Instruction Manual

(M) Monitor display and monitor output signal
5.11.1

## Speed display and rotations per minute setting

The monitor display unit and the frequency setting on the operation panel can be switched to motor
speed and machine speed.
Pr.
37
M000
505
M001
144
M002
811
D030
The maximum value of the setting range differs according to the Pr. 1 "Maximum frequency", Pr. 505
"Speed setting reference", and it can be calculated from the following formula.
The maximum value of Pr. 37 < 65535 × Pr. 505 / Pr. 1 setting value (Hz).
The maximum setting value of Pr. 37 is 9998 if the result of the above formula exceeds 9998.
Display in speed (Pr. 37, Pr. 144)
● Set the number of motor poles (2, 4, 6, 8, 10, 12) for Pr. 144, or the number of motor poles + 100
(102, 104, 106, 108, 110, 112) to display the motor speed.
● The Pr. 144 setting will change automatically when setting the motor poles with Pr. 81 "Number
of motor poles". Pr. 81 will not automatically change when Pr. 144 is changed.
● Example 1: Changing the initial value of Pr. 81 to "2" or "12" will change Pr. 144 from "4" to "2".
● Example 2: When setting Pr. 81 = "2" while Pr. 144 = "104", Pr. 144 will change from "104" to "102".
Display in motor speed (Pr. 37, Pr. 505)
● To display in the machine speed, set Pr. 37 to the machine speed at the frequency set in Pr. 505.
● For example, when Pr. 505 = "60 Hz" and Pr. 37 = "1000", the running speed monitor will display
"1000" at the running speed of 60 Hz.When running frequency is 30 Hz, "500" is displayed.
Changing the monitored value and speed setting increment (Pr. 811)
● When Pr. 811 = "1 or 11", the speed setting for PU input and RS-485 communication, speed setting
from communication option and the running speed monitor will be in increments of 0.1 r/min.
● For availability of changing the speed setting increments via communication options, refer to the
Instruction Manual of each communication option.
5 - 324
Initial value
Name
FM
Speed display
Speed setting
60 Hz
reference
Speed setting
switchover
Set resolution
switchover
Setting range
CA
0
0
1 to 9998
50 Hz
1 to 590 Hz
0, 2, 4, 6, 8, 10, 12,
4
102, 104, 106, 108,
110, 112
0
0
1
10
11
Description
Frequency display and setting
Set the machine speed for Pr. 505.
Set the reference speed for Pr. 37.
Set the number of motor poles when
displaying the motor speed.
Speed setting, running
speed monitor
setting increments
increments on PU,
RS-485 communication,
Pr. 812 to Pr. 817
communication options
1 r/min
0.1 r/min
1 r/min
0.1 r/min
Parameters
Torque limit
Pr. 22,
0.1%
0.01%