2.12 Wiring Of Several Inverters To One Converter - Mitsubishi Electric FR-HC2-7.5K Instruction Manual

Wiring of several inverters to one converter

2.12 Wiring of several inverters to one converter

Up to ten inverters can be connected to one converter. Be sure to use a converter with the capacity higher than the total
capacities of inverters. Additionally, the total capacity of the inverters needs to be higher than half the converter capacity.
If the total inverter capacity is less than half the converter capacity, the converter can be used as a common converter or a
regenerative converter. However, it's harmonic suppression effect reduces.
(1) Junction terminals or cross wiring are used to connect several inverters, so carefully select the wire gauge. Start adding
the inverter capacities from the furthest inverter.
(2) When connecting several inverters, connect starting with the inverter with the highest capacity.
(3) Installation of a fuse, which corresponds with each motor capacity, is recommended for each inverter when connecting
several inverters to one converter. Select a fuse according to the motor capacity.
When using a motor, of which capacity is smaller than the inverter capacity by two ranks or more, select the converter
capacity according to the inverter capacity. (Refer to page 11 and 13.)
(4) Keep the total wiring length within 50m.
Main circuit wiring example
The following diagram shows a connection example when connecting six inverters in total (FR-A720-30K, 15K, 5.5K, 2.2K,
1.5K, and 0.75K) to FR-HC2-55K.
Junction terminal 1
1)
P
FR-HC2
-55K
N
3)
Junction terminal 2
5)
Junction terminal 3
7)
Junction terminal 4
9)
Junction terminal 5
11)
Junction terminal 6
56
INV1
Fuse
P
30kW
2)
A720
Motor
30K
N
1st inverter
INV2
P
15kW
4)
A720
Motor
Motor
N 15K
2nd inverter
INV3
P
5.5kW
6)
A720
Motor
5.5K
N
3rd inverter
INV4
P
2.2kW
8)
A720
Motor
2.2K
N
4th inverter
INV5
P
1.5kW
A720
10)
Motor
1.5K
N
5th inverter
INV6
P
0.75kW
12)
A720
Motor
0.75K
N
6th inverter
1) Wire gauge between FR-HC2 and the junction terminal 1 is 100mm
according to the FR-HC2 capacity.
2) Wire gauge between the junction terminal 1 and the inverter is 60mm
because the inverter capacity is 30K.
3) Wire gauge between the junction terminal 1 and junction terminal 2 can be
calculated as follows: 15+5.5+2.2+1.5+0.75=24.95K, and 24.95K rounds
up to 30K, so the wire gauge is 60mm
4) The Wire gauge between the junction terminal 2 and the inverter is 22mm
because the inverter capacity is 15K.
5) Wire gauge between the junction terminal 2 and junction terminal 3 can be
calculated as follows: 5.5+2.2+1.5+0.75=9.95K, and 9.95K rounds up to
11K, so the wire gauge is 14mm
6) Wire gauge between the junction terminal 3 and the inverter is 14mm
because the inverter capacity is 5.5K.
7) Wire gauge between the junction terminal 3 and junction terminal 4 can be
calculated as follows: 2.2+1.5+0.75=4.45K, and 4.45 K rounds up to 5.5K,
2
so the wire gauge is 5.5mm .
8) Wire gauge between the junction terminal 4 and the inverter is 2mm
because the inverter capacity is 2.2K.
9) Wire gauge between the junction terminal 4 and junction terminal 5 can
be calculated as follows: 1.5+0.75=2.25K, and 2.25K rounds down to
2.2K, so the wire gauge is 2mm
10) Wire gauge between the junction terminal 5 and the inverter is 2mm
because the inverter capacity is 1.5K.
11) Wire gauge between the junction terminal 5 and junction terminal 6 is
2
2mm because the inverter capacity is 0.75K.
12) Wire gauge between the junction terminal 6 and the inverter is 2mm
because the inverter capacity is 0.75K.
2
.
2
.
2
.
2
2
2
2
2
2
2