Mitsubishi Electric MR-J4 Instruction Manual page 313

11. OPTIONS AND PERIPHERAL EQUIPMENT
(3) MR-J4-11KB(-RJ) to MR-J4-22KB(-RJ)/MR-J4-11KB4(-RJ) to MR-J4-22KB4(-RJ) (when using the
supplied regenerative resistor)
CAUTION
When using the regenerative resistors supplied to the servo amplifier, the specified number of resistors
(4 or 5 resistors) must be connected in series. If they are connected in parallel or in less than the
specified number, the servo amplifier may become faulty and/or the regenerative resistors burn.
Install the resistors at intervals of about 70 mm. Cooling the resistors with two cooling fans (1.0 m
or more, 92 mm × 92 mm) improves the regeneration capability. In this case, set "_ _ F A" in [Pr. PA02].
Servo amplifier
MR-J4-11KB(-RJ)
MR-J4-15KB(-RJ)
MR-J4-22KB(-RJ)
MR-J4-11KB4(-RJ)
MR-J4-15KB4(-RJ)
MR-J4-22KB4(-RJ)
The regenerative resistor supplied with 11 kW to 22 kW servo amplifiers does not
have a protect cover. Touching the resistor (including wiring/screw hole area) may
cause a burn injury and electric shock. Even if the power was shut-off, be careful
until the bus voltage discharged and the temperature decreased because of the
following reasons.
It may cause a burn injury due to very high temperature without cooling.
It may cause an electric shock due to charged capacitor of the servo amplifier.
5 m or less
(Note) Series connection
Cooling fan
Note. The number of resistors connected in series depends on the resistor type. The
thermal sensor is not mounted on the attached regenerative resistor. An abnormal
heating of resistor may be generated at a regenerative circuit failure. Install a thermal
sensor near the resistor and establish a protective circuit to shut off the main circuit
power supply when abnormal heating occurs. The detection level of the thermal
sensor varies according to the settings of the resistor. Set the thermal sensor in the
most appropriate position on your design basis, or use the thermal sensor built-in
regenerative option. (MR-RB5R, MR-RB9F, MR-RB9T, MR-RB5K-4, or MR-RB6K-4)
Regenerative resistor
GRZG400-0.8Ω
GRZG400-0.6Ω
GRZG400-0.5Ω
GRZG400-2.5Ω
GRZG400-2Ω
Servo amplifier
P+
C
Regenerative power [W]
Normal
500
850
500
850
11 - 18
Resultant
resistance [Ω]
Cooling
800 3.2
3
1300
2.5
800 10
1300 10
3
/min
Number of
resistors
4
5
4
5