Thermal Protection Of The Resistors; Protecting The Resistor Cable Against Short-Circuits; Mechanical Installation Of Custom Brake Resistors; Electrical Installation Of Custom Brake Resistors - ABB ACS880-37 Hardware Manual

Thermal protection of the resistors

The standard resistors available as option +D151 are equipped with a thermal switch. The
switches of the resistors are wired in series and connected to the Enable input of the brake
chopper. The relay output of the chopper is wired to the supply control unit so that a
chopper fault condition stops the supply unit.
With custom resistors, a similar protection must be implemented. Use cable rated as
follows:
•
twisted pair, shielding recommended
•
rated operating voltage between a conductor and ground (U
•
insulation test voltage > 2.5 kV.
Keep the cable as short as possible.

Protecting the resistor cable against short-circuits


The input fuses of the drive will also protect the resistor cable provided that the resistor
cable is of the same type as the input cable.

Mechanical installation of custom brake resistors

Follow the resistor manufacturer's instructions.

Electrical installation of custom brake resistors

Connection diagram


Brake chopper
R+ R‚
1 2
R+ R‚
Brake resistor
X1
1 2
3
t°
Resistor braking 255
) > 750 V
0