Adtech iMASTER – A1 Series User Manual page 26

A1-User's Manual
3) Regenerative Braking Unit Terminals: P, N ( >= 30kW(40HP) Units)
VFDs rated greater than and equal to 30KW (40HP) do not contain an internal BRD

circuit. If regenerative braking is going to occur, then an external BRD circuit (Option)
is required along with a resistor. (Option)
Connect external regenerative braking unit terminals (P,N)

to terminals (P,N) on the VFD.
The braking resistor is then wired into the External BRD board,

not directly to the VFD.
The cable length between the VFD and the BRD board, BRD board and the resistor,

should be less than 16 feet and twist the connecting wires to reduce inductance.
4) Earth Ground: G
Make sure that you securely ground the VFD and motor

for prevention of electric shock.
The VFD and motor must be connected to an appropriate safety earth ground and

follow all local electrical codes.
In case connecting 2 or more VFDs, use caution not to create a ground loop situation

which may cause the VFD to malfunction. Use a star configuration grounding
technique.
Grounding wire should be as short as possible and should be connected
to the ground point as near as possible to the VFD.
VFD Frame
F1
F2
F3
F4
F5
F6
INVERTER
INVERTER
INVERTER
INVERTER
INVERTER
INVERTER
Earth Ground (G) Connection
Grounding Wire Size (mm
200V class
14/27.6
22/43.4
53.5/ 105.6
85.0/ 167.8
85.0/ 167.8
85.0/ 167.8
２２
/kcmil)
2
400V class
8/15.9
14/27.6
33.6/ 66.4
53.5/ 105.6
85.0/167.8
85.0/167.8