Toshiba Tosvert VF-S15 Instruction Manual page 38

Circuit breaking when two or more inverters are used on the same power line
1
If power supply distortion is not negligible
If multiple inverters are connected with common DC bus link
 Disposal
Refer to chapter 16.
MCCB1
There is no fuse in the inverter's main circuit. Thus, as the diagram above shows, when more than one
inverter is used on the same power line, you must select interrupting characteristics so that only
MCCB2 to MCCBn+1 will trip and the MCCB1 will not trip when a short occurs in the inverter (INV1).
When you cannot select the proper characteristics install a circuit interrupting fuse behind MCCB2 to
MCCBn+1.
If the power supply distortion is not negligible because the inverter shares a power distribution line
with other systems causing distorted waves, such as systems with thyristors or large-capacity
inverters, install an input AC reactor to improve the input power factor, to reduce higher harmonics, or
to suppress external surges.
When inverters are fed by AC power supply and connected with common DC bus link, ground fault trip
protection may operate. In that case, set ground fault detection selection ( f614 ) to 0 "Disabled".
MCCB2 (circuit breaking fuse)
MCCB3
MCCBn  1
Breaking of selected inverter
A-26
E6581926
INV1
INV2
MCCB:
Molded-case
circuit breaker
INVn