232 Resistor braking
Electrical installation
Checking the insulation of the assembly
Obey the instructions given in section Brake resistor and resistor cable on page 86.
Connection diagram
See section Power cable connection diagram on page 94.
Connection procedure
• Connect the brake chopper via fuses (see section Brake choppers on page 232) to
drive module terminals UDC+ and UDC-.
• Connect the resistor cables to the brake chopper terminals. If a shielded three-
conductor cable with shield conductivity good enough for the protective earth (ground)
conductor is used, cut the third conductor. If the shield conductivity is not good
enough, use the third conductor as the PE conductor. Ground the twisted shield of the
cable (protective earth conductor of the resistor assembly) as well as any separate PE
conductor (if present) at both ends.
• Connect the thermal switch of the brake resistor as described in section Protecting the
system against thermal overload on page 231.
WARNING! The ENABLE input terminal block of the brake chopper is at
intermediate circuit potential when the line-side converter of the drive is running.
This voltage is extremely dangerous and can cause serious damage or injury if
the isolation level and protection conditions for the thermal switches are not sufficient.
Insulate the thermal switches correctly (over 2.5 kV) and shroud them against contact.
Start-up
Set the following parameters (ACS880 primary control program):
• Disable the overvoltage control of the drive by parameter 30.30 Overvoltage control.
For settings of other control programs, see the appropriate firmware manual.
Note: Some brake resistors are coated with oil film for protection. At the start-up, the
coating burns off and produces a little bit of smoke. Make sure there is sufficient ventilation
at the start-up.
Technical data
Ratings
Brake choppers
This table shows the optional default brake choppers of the drive with the ratings and
fuses for the brake choppers. Cubicle width 400 mm.
Drive
module type
ACS880-34-
Fuses Cable
(chopper
–drive)
Brake chopper
Manufacturer Type Type P
br,max,
40 s
I
max
E
r
A
mm
2
kW A kJ
U
N
= 400 V