Electrical Connections; Safety First; Voltage Supply; Disconnect Switch - KEB Combivert F5 series Instruction Manual

1.5 Electrical connections

1.5.1 Safety First

RISK OF ELECTRIC SHOCK! Always disconnect supply voltage before servicing
the COMBIVERT F5.
After disconnecting the supply voltage, always wait 5 minutes before attempting
to change the wiring. The internal DC BUS capacitors must discharge.

1.5.2 Voltage Supply

The F5 series inverters are suitable for use on a circuit capable of delivering not more than
10kA rms symmetrical amperes, at the inverter's rated maximum voltage.
Pay attention to the supply voltage and be sure the supply voltage matches that of the
inverter. A 230V unit can be supplied with voltage in the range 180 to 260VAC +/-0%, for
a 460V unit the range is 305 to 500VAC +/- 0%, 48Hz to 62 Hz.
Connection of the F5 series inverters to voltage systems configured as a corner
grounded delta, center tap grounded delta, open delta, or ungrounded delta, may
defeat the internal noise suppression of the inverter and the isolation of the control
part is no longer classified as a "securely isolated circuit". Increased high
frequency disturbance in the machine and on the line may be experienced. On such
a system the maximum allowable phase to ground voltage is 500VACrms. A
balanced, center grounded wye connection is always recommended. The three
phase voltage imbalance must be less than 2% phase to phase. Greater imbalance
can lead to damage of the inverter's power circuit.

1.5.3 Disconnect Switch

A disconnect switch or contactor should be provided as a means of turning off the supply
voltage when the unit is not in use or when it must be serviced.
Repetitive cycling on and off of the input supply voltage more than once every five minutes
can lead to damage of the inverter. For shorter times contact KEBCO.
A disconnect or switch placed between the motor and inverter should be avoided
if at all possible. However, if not, the following points should be considered. It is
not allowed to actively switch the motor on a closed loop (Field Oriented Control
induction or AC servo) system. The inverter must first be brought into NOP status
by turning off the drive enable input on terminal X2.16. On openloop systems,
switching off a motor running under load can cause the COMBIVERT F5's
overcurrent protection to activate resulting in a fault shut down of the unit. When
starting motors by closing the contact into an already running inverter, the inverter
should be sized based on the starting current of the motor. Or to reduce the current
demand, the "speed search" function of the inverter should be activated.
General
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