
2-14
DC link bus terminals P(+) and N(-)
Capacity
(HP)
Braking
transistor
Built-in DC braking
resistor (DBR)
Optional devices
Devices and terminals
50 to 1000
None
None
Braking unit
Inverter - Braking unit:
P(+) and N(-)
DC braking resistor
(DBR)
Braking unit -DBR:
P(+) and DB
1) Connecting an optional braking unit or DC braking resistor (DBR)
Inverters of 50 HP or above require both a braking unit and DBR.
Connect the terminals P(+) and N(-) of a braking unit to those on the inverter. Arrange the inverter and the braking
unit so that the wiring length comes to 16 ft (5 m) or less and twist the two wires or route them together in parallel.
Next, connect the terminals P(+) and DB of a DBR to those on the braking unit. Arrange the braking unit and DBR
so that the wiring length comes to 33 ft (10 m) or less and twist the two wires or route them together in parallel.
For details about the wiring, refer to the Braking Unit Instruction Manual.
2) Connecting other external devices
A DC link bus of other inverter(s) or a PWM converter is connectable to these terminals.
When you need to use the DC link bus terminals P(+) and N(-), consult your TECO-Westinghouse Motor
Company representative.
Switching connectors
Power switching connectors (CN UX) (on inverters of 125 HP or above for 460 V)
Inverters of 125 HP or above for 460 V are equipped with a set of switching connectors (male) which should be
configured according to the power source voltage and frequency. By factory default, a jumper (female connector) is set
to U1. If the power supply to the main power inputs (L1/R, L2/S, L3/T) or the auxiliary fan power input terminals (R1,
T1) matches the conditions listed below, change the jumper to U2.
For the switching instructions, see Figures 2.6 and 2.7.
(a) EQ7-4125-C to EQ7-4200-C
Connector
configuration
Power source voltage
398 to 440 V/50 Hz, 430 to 480 V/60 Hz
(Factory default)
380 to 398 V/50 Hz
380 to 430 V/60 Hz
(b) EQ7-4250-C to EQ7-41000-C
Connector configuration
Power source voltage
398 to 440 V/50 Hz, 430 to 480 V/60 Hz
(Factory default)
380 to 398 V/50 Hz,
380 to 430 V/60 Hz
The allowable power input voltage fluctuation is within -15% to +10% of the power source voltage.
CN UX (red)
CN UX (red)
CN UX (red)
CN UX (red)