Toshiba TOSVERT VF-S9 Instruction Manual page 24

Circuit interrupting when two or more inverters are used on the same power line.
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 the
MCCB2 will trip and the MCCB1 will not trip when a short occurs in the inverter (INV1). When you can-
not select the proper characteristics install a circuit interrupting fuse between the MCCB2 and the INV1.
Disposal
If an inverter is no longer usable, dispose of it as industrial waste.
1.4.3 What to do about leak current
Current may leak through the inverter's input/output wires because of insufficient electrostatic capacity on the motor with
bad effects on peripheral equipment. The leak current's value is affected by the carrier frequency and the length of the in-
put/output wires. Test and adopt the following remedies against leak current.
(1) Effects of leak current across ground
Leak current may flow not just through the inverter system but also through ground wires to other sys-
tems. Leak current will cause earth leakage breakers, leak current relays, ground relays, fire alarms
and sensors to operate improperly, and it will cause superimposed noise on the CRT screen or display
of incorrect current amounts during current detection with the CT.
MCCB1 MCCB2
MCCB3
MCCBn+1
Breaking of selected inverter
Warning
A-13
(circuit interupting fuse)
INV1
INV2
INVn
E6580757
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