Mitsubishi Electric MELSERVO-J4 series, Instruction Manual

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11 OPTIONS AND PERIPHERAL EQUIPMENT
11.2 Regenerative options
MR-J4-11KGF(-RJ) to MR-J4-22KGF(-RJ)/MR-J4-11KGF4(-RJ) to MR-J4-22KGF4(-RJ)
(when using the supplied regenerative resistor)
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
3
/min or more, 92 mm

92
mm) improves the regeneration capability. In this case, set "_ _ F A" in [Pr. PA02].
*1 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 the
design basis of the device, or use the thermal sensor built-in regenerative option. (MR-RB5R, MR-RB9F, MR-RB9T, MR-RB5K-4, or
MR-RB6K-4)
*1 The following shows an indication example of symbol.
CAUTION
• The regenerative resistor supplied with 11 kW to 22 kW servo amplifiers does not have a protective 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.

It may cause an electric shock due to charged capacitor of the servo amplifier.
• Do not use servo amplifiers with external regenerative resistors other than the combinations specified below. Otherwise, it may cause a fire.
Servo amplifier Regenerative
resistor Symbol
*1
Regenerative power [W] Resultant
resistance [

]
Number of
resistors
Normal Cooling
MR-J4-11KGF(-RJ) GRZG400-0.8

GR400 R80K 500 800 3.2 4
MR-J4-15KGF(-RJ) GRZG400-0.6

GR400 R60K 850 1300 3 5
MR-J4-22KGF(-RJ) GRZG400-0.5

GR400 R50K 2.5
MR-J4-11KGF4(-RJ) GRZG400-2.5

GR400 2R5K 500 800 10 4
MR-J4-15KGF4(-RJ)
MR-J4-22KGF4(-RJ) GRZG400-2

GR400 2R0K 850 1300 10 5
P+
C
Servo amplifier
Cooling fan
Series connection *1
5 m or less
GR400 R80K
Symbol
Regenerative resistor