Optidrive HVAC User Guide V2.00
www.invertekdrives.com
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4
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4.1.2.
Grounding Guidelines
The ground terminal of each Optidrive should be individually connected DIRECTLY to the site ground bus bar (through the filter if installed).
Optidrive ground connections should not loop from one drive to another, or to, or from any other equipment. Ground loop impedance must
confirm to local industrial safety regulations. To meet UL regulations, UL approved ring crimp terminals should be used for all ground wiring
connections.
The drive Safety Ground must be connected to system ground. Ground impedance must conform to the requirements of national and local
industrial safety regulations and/or electrical codes. The integrity of all ground connections should be checked periodically.
4.1.3.
Protective Earth Conductor
The Cross sectional area of the PE Conductor must be at least equal to that of the incoming supply conductor.
4.1.4.
Safety Ground
This is the safety ground for the drive that is required by code. One of these points must be connected to adjacent building steel (girder, joist),
a floor ground rod, or bus bar. Grounding points must comply with national and local industrial safety regulations and/or electrical codes.
4.1.5.
Motor Ground
The motor ground must be connected to one of the ground terminals on the drive.
4.1.6.
Ground Fault Monitoring
As with all inverters, a leakage current to earth can exist. The Optidrive is designed to produce the minimum possible leakage current whilst
complying with worldwide standards. The level of current is affected by motor cable length and type, the effective switching frequency, the
earth connections used and the type of RFI filter installed. If an ELCB (Earth Leakage Circuit Breaker) is to be used, the following conditions
apply: -
A Type B Device must be used
The device must be suitable for protecting equipment with a DC component in the leakage current
Individual ELCBs should be used for each Optidrive
Drives with an EMC filter have an inherently higher leakage current to Ground (Earth). For applications where tripping occurs the EMC filter
can be disconnected (on IP20 units only) by removing the EMC screw on the side of the product.
Remove the screws as indicated below
The Optidrive product range has input supply voltage surge suppression components fitted to protect the drive from line voltage transients,
typically originating from lightning strikes or switching of high power equipment on the same supply.
4.1.7.
Shield Termination (Cable Screen)
The safety ground terminal provides a grounding point for the motor cable shield. The motor cable shield connected to this terminal (drive
end) should also be connected to the motor frame (motor end). Use a shield terminating or EMI clamp to connect the shield to the safety
ground terminal.
4.2.
Wiring Precautions
Connect the Optidrive according to section 4.3 and 4.4, ensuring that motor terminal box connections are correct. There are two connections
in general: Star and Delta. It is essential to ensure that the motor is connected in accordance with the voltage at which it will be operated. For
more information, refer to section 4.5 Motor Terminal Box Connection.
It is recommended that the power cabling should be 4-core PVC-insulated screened cable, laid in accordance with local industrial regulations
and codes of practice.
Internal
EMC
Filter
Internal
Surge
Protection
Earth
