Motor Thermal Protection - Danfoss VLT AutomationDrive FC 300 Design Manual

6. How to Install
6.8.7. Direction of Motor Rotation
The default setting is clockwise rotation with the frequency converter
output connected as follows.
Terminal 96 connected to U-phase
Terminal 97 connected to V-phase
Terminal 98 connected to W-phase
Thedirection of motor rotation is changed by switching two motor phases.
6

6.8.8. Motor Thermal Protection

The electronic thermal relay in the frequency converter has received the UL-approval for single motor protection, when par. 1-90
tion ETR Trip
is set for
For thermal motor protection it is also possible to use the MCB 112 PTC Thermistor Card option. This card provides ATEX certificate to protect motors in
explosion hazardous areas, Zone 1/21 and Zone 2/22. Please refer to the
6.9.1. Installation of Brake Cable
(Only for frequency converters ordered with brake chopper option).
The connection cable to the brake resistor must be screened.
1. Connect the screen by means of cable clamps to the conductive
back plate on the frequency converter and to the metal cabinet
of the brake resistor.
2. Size the brake cable cross-section to match the brake torque.
See Brake instructions, MI.90.FX.YY and MI.50.SX.YY for more information about safe installation.
NB!
Voltages up to 960 V DC, depending on the supply voltage, may occur on the terminals.
6.9.2. RS 485 Bus Connection
One or more frequency converters can be connected to a control (or
master) using the RS485 standardized interface. Terminal 68 is connec-
ted to the P signal (TX+, RX+), while terminal 69 is connected to the N
signal (TX-,RX-).
If more than one frequency converter is connected to a master, use par-
allel connections.
138
Motor current, I
and par. 1-24 is set to the rated motor current (see motor name plate).
M,N
MG.33.BA.02 - VLT
Design Guide for further information.
No. Function
81, 82 Brake resistor terminals
® is a registered Danfoss trademark
FC 300 Design Guide
Motor Thermal Protec-