Selection Of Circuit Protectors - Mitsubishi Electric MELDAS MDS-B-SVJ2 Series Specifications And Instruction Manual

7-2 Selection of circuit protectors

Use the following table to obtain the circuit protector rated current from the total rated capacity (SVJ2
total output capacity) of the motor driving the SVJ2 servo amplifier to be connected to the circuit
protector to be selected, and select the circuit protector.
When the MDS-B-SPJ2 spindle amplifier or converter unit will share circuit protectors, select from the
total circuit protector rated current of each SVJ2 total output capacity and SPJ2 spindle amplifier or
converter unit. However, separate the SVJ2 servo amplifier circuit protector from the others, and
select the NF60 type (60A) or smaller capacity dedicated for SVJ2 servo amplifiers if the total circuit
protector rated current exceeds 60A.
SVJ2 total rated capacity
Circuit protector
rated current
MDS-B-SPJ2-02
MDS-B-SPJ2-04
MDS-B-SPJ2
MDS-B-SPJ2-075
MDS-B-SPJ2-15
MDS-A-CR-10
Converter unit
MDS-A-CR-15
Circuit protector
rated current
Circuit protector
rated current
Recommended
Circuit protector
(Mitsubishi Electric Corp.:
Option part)
(Example 1)
The circuit protector is selected for the MDS-B-SVJ2-10 with 3 HC102 axes and an MDS-B-SPJ2-75
axis connected.
Because there are 1kW × 3 = 3kW on the SVJ2 side, 20A is selected from the table for the circuit
protector rated current.
40A is selected from the table for the SPJ2-75 rated current.
Therefore, the total rated current is 60A, and the NF60-CP3P60A is selected.
(Example 2)
The circuit protector is selected for the MDS-B-SVJ2-20 with 2 HC202 axes and an MDS-B-CR-90
connected.
Because there are 2kW × 2 = 4kW on the SVJ2 side, 30A is selected from the table for the circuit
protector rated current.
50A is selected from the table for the MDS-B-CV-90 rated current.
Therefore, the total rated current is 80A. The circuit protector is separated from converter unit,
and the NF30-CS3P30A is selected for the SVJ2. (Refer to the "MDS-A/B Series Specifications
Manual" for details on selecting the converter circuit protector.)
DANGER
Chapter 7 Peripheral Devices
Circuit protector rated current table
1.5kW or less 3.5kW or less
10A 20A
MDS-B-SPJ2-22
MDS-B-SPJ2-37
MDS-C1-CV-37
MDS-A-CR-22
MDS-A-CR-37
10A 20A
Circuit protector selection table
10A 20A
NF30-CS3P NF30-CS3P
10A 20A
Install independent circuit protectors and contactors as the SVJ2 main circuit
power supply if the total current capacity exceeds 60A when the power supply
is shared between the converter and a large capacity SPJ2 spindle amplifier.
Circuit protectors may not operate for short-circuits in small capacity amplifiers
if they are shared with a large capacity unit, and this could cause fires. For the
SVJ2, use an NF60 type or lower capacity breaker.
7kW or less 10kW or less
30A 40A
MDS-B-SPJ2-55 MDS-B-SPJ2-75
MDS-C1-CV-55 MDS-C1-CV-75
MDS-A-CR-55 MDS-A-CR-75
30A
30A 40A
NF30-CS3P NF50-CP3P
30A 40A
7-3
13kW or less 16kW or less
50A 60A
MDS-B-SPJ2-110
MDS-A-CR-90
MDS-C1-CV-110
40A 50A
50A 60A
NF50-CP3P NF60-CP3P
50A 60A