Table of Contents
Advertisement
32 Guidelines for planning the electrical installation
• Each output of the brake chopper module must feed a resistor of its own. There is one
output in the 1-phase brake chopper module, and 3 outputs in the 3-phase brake chopper
module.
• The resistance (R) of the brake resistor must be equal to or above the value specified.
Never use resistance values below the specified value.
• The brake resistor must withstand the specified brake cycles.
• The ventilation of the space/room in which the brake resistor is located must meet the
air flow amounts specified.
• The resistor must be equipped with a thermal switch.
WARNING!
IEC 60664 and IEC 61800-5-1 require double or reinforced insulation between
resistor live parts and the sensor. If the resistor assembly does not fulfill the
requirement, the I/O terminals on the control unit must be protected against contact
and must not be connected to other equipment, or the temperature sensor must
be isolated from the I/O terminals, for example, with a suitable relay.
Selecting and routing the brake resistor cables
Typical resistor cable sizes
￭
See the technical data.
Minimizing electromagnetic interference
￭
Obey these rules in order to minimize electromagnetic interference caused by the rapid
current changes in the resistor cables:
• Shield the braking power line completely, either by using shielded cable or a metallic
enclosure. Unshielded single-core cable can only be used if it is routed inside a cabinet
that efficiently suppresses the radiated emissions.
• Install the cables away from other cable routes.
• Avoid long parallel runs with other cables. The minimum parallel cabling separation
distance is 0.3 meters (1 ft).
• Cross the other cables at 90 degree angles.
• Keep the cable as short as possible in order to minimize the radiated emissions and
stress on chopper IGBTs. The longer the cable the greater the radiated emissions,
inductive load and voltage peaks over the IGBT semiconductors of the brake chopper.
Note: ABB has not verified that the EMC requirements are fulfilled with custom brake
resistors and cabling. The customer must consider the EMC compliance of the complete
installation.
Maximum cable length
￭
See the technical data.
Placing the brake resistor
Install the resistor assembly outside the drive in a place where it is able to cool effectively.
Arrange the cooling of the resistor in a way that:
Advertisement
Table of Contents
