Electrical installation of compressor and frequency inverter
This chapter covers some important aspects to be considered when installing and commissioning an external frequency inverter.
- For frequency inverters not manufactured by Bitzer: Please refer also to the respective operating instructions!
- For the Bitzer Varipack frequency inverters (incl. electrical connections and control functions):
- For schematic wiring diagrams for various compressors with frequency inverter:
- AT-300: Schematic wiring diagrams for BITZER products
For further information, see also ASERCOM Guidelines "Recommendations for using frequency inverters with positive displacement refrigerant compressors", chapter 6.
State of delivery of compressor:
![](../assets/img/SmallWarningYellow.gif)
![](../assets/img/SmallWarningYellow.gif)
The compressor is filled with a protective charge: Excess pressure 0.5 .. 1 bar nitrogen.
Risk of injury to skin and eyes.
Depressurise the compressor!
Wear safety goggles!
For work on the electrical system:
![](../assets/img/SmallWarningYellow.gif)
![](../assets/img/SmallWarningYellow.gif)
Risk of electric shock!
Before working on the terminal box, module housing and electrical lines: Switch off the main switch and secure it against being switched on again!
Close the terminal box and the module housing before switching on again!
For work on the frequency inverter (FI):
![](../assets/img/SmallWarningYellow.gif)
![](../assets/img/SmallWarningYellow.gif)
Life-threatening voltages inside the frequency inverter housing!
Contact can lead to serious injuries or death.
Never open the FI housing in operation! Switch off the main switch and secure it against being switched on again.
Wait for at least 10 minutes until all capacitors have been discharged!
Before switching on again, close the FI housing.
![](../assets/img/SmallWarningYellow.gif)
![](../assets/img/SmallWarningYellow.gif)
Wrong or insufficient earthing may result in life-threatening electric shocks upon contact with the frequency inverter!
Earth the complete frequency inverter permanently and check the earth contacts at regular intervals!
Prior to any intervention in the device, check all voltage connections for proper isolation.
Operating the frequency inverter at high temperatures leads to stress and reduced lifetime!
Take into account the maximum ambient temperatures at the place of installation.
Observe the minimum clearances for ventilation.