Instruction Manual Supplement
Instructions for compliance with the EU Directives
The standard is as follows.
• EMC Directive: 2014/30/EC
• Standard: EN 61800-3:2004+A1:2012 (Second environment / PDS Category C3)
The FR-A806 is compliant with the following standard.
EN 61800-3:2004+A1:2012 (First environment / PDS Category C2, Second environment / PDS Category C3
The applicable standard depends on the type of the built-in EMC filter.
Motor overload protection
To use the electronic thermal function for motor overload protection, set a rated motor current in Pr.9 Electronic
thermal O/L relay.
Operational characteristic of the electronic thermal relay
Pr. 9 = 50% setting of
Pr. 9 = 100% setting
of inverter rating*
30Hz or more*
Inverter output current (%)
(% to the rated output current)
• The internal accumulated heat value of the electronic thermal O/L relay is reset to the initial value by the inverter's
power reset or reset signal input. Avoid unnecessary reset and power-OFF.
• When multiple motors are driven with a single inverter or when a multi-pole motor or a special motor is driven, install
an external thermal relay (OCR) between the inverter and motors. When setting an external thermal relay, note that
the current indicated on the motor rating plate is affected by the line-to-line leakage current. (Refer to the Instruction
• The cooling effect of the motor drops during low-speed operation. Use a thermal protector or a motor with built-in
• When the difference between the inverter and motor capacities is large and the set value is small, the protective
characteristics of the electronic thermal relay function will be deteriorated. In such case, use an external thermal
• A special motor cannot be protected by the electronic thermal relay function. Use an external thermal relay.
• Set Pr.9 = "0" for Vector-control-dedicated motors (SF-V5RU) because they are equipped with built-in thermal
• Motor over temperature sensing is not provided by the drive.
• Electronic thermal memory retention function is not provided by the drive.
This function detects the overload of the motor, stops the operation of the inverter's output
transistor, and stops the output. (The operation characteristic is shown on the left.)
Range on the right of
Range on the left of
Characteristic when electronic thermal
relay function for motor protection is
turned off (When Pr. 9 setting is 0(A))
• When using the Mitsubishi Electric constant-torque motor
Set Pr.71 = "1, 13 to 16, 50, 53, or 54". (This provides a 100% con-
tinuous torque characteristic in the low-speed range.)
Set the rated motor current in Pr.9.
When a value 50% of the inverter rated output current (current value) is
set in Pr.9
The % value denotes the percentage to the inverter rated output
current. It is not the percentage to the rated motor current.
When the electronic thermal relay function dedicated to the Mitsubishi
Electric constant-torque motor is set, this characteristic curve applies to
operation at 6 Hz or higher.
Transistor protection is activated depending on the temperature of the
heatsink. The protection may be activated even with less than 150%
depending on the operating conditions.