A.1 Calculation Of The Motor Voltage - KEB COMBIVERT G6 series Installation Manual

Annex
Annex A
A.1 Calculation of the motor voltage
The motor voltage for dimensioning of the drive is depending on the used components. The
mains voltage reduces according to the following table:
Mains choke Uk
Inverter open loop
Inverter closed loop 8 %
Motor choke Uk
Non-rigid
system
A.2 Maintenance
All work may only be done by qualified personnel. The security must be ensured as follows:
• Disconnect power supply at MCCB
• Secure against restarting
• Await discharge time of capacitors
(if necessary controlling by measurement at "++" and „--")
• Ensure loss of voltage by measurement
In order to avoid premature ageing and avoidable malfunctions, the measures mentioned
below must be carried out in the appropriate cycle.
Cycle
Constant
Monthly
A.3 Shut down
A.3.1 Storage
The DC link of the KEB COMBIVERT is equipped with electrolytic capacitors. If electrolytic
capacitors are stored de-energized, the oxide film working as dielectric fluid reacts with the
acidic electrolyte and destroy themselves slowly. This affects the dielectric strength and the
capacity.
If the capacitor starts running with rated voltage, it is tried to build the oxide film abrupt again.
This causes heat and gas and leads to the destruction of the capacitor.
In order to avoid defectives, the KEB COMBIVERT must be started up depending on the sto-
rage period in accordance with the following specification:
GB - 38
4 %
4 %
1 %
supply 2 %
Function
Pay attention to unusual noises of the motor (e.g. vibrations) as well as of the
frequency inverter (e.g. fan).
Pay attention to unusual smells of the motor or frequency inverter (e.g. evapo-
ration of capacitor electrolyte, braise of the motor winding)
Check unit for loose screws and plugs and if necessary tighten up.
Clean frequency inverter from dirt and dust deposits. Pay attention especially
to cooling fins and protective grid of the fans.
Examine and clean extracted air filter and cooling air filter of the control cabi-
net.
Examine function of the fans of the KEB COMBIVERT. The fan must be repla-
ced in case of audible vibrations or squeak.
Make a visual leak test of the cooling circuit for water-cooled inverters.
Example:
Closed loop inverter with mains- and motor choke at
non-rigid supply system:
400 V mains voltage - 15 % = 340 V motor voltage