Delta Electronics VFD007S23A User Manual

Chapter 2 Installation and Wiring|VFD-S Series 

2-22 

 Revision August 2006, SE08, SW V2.61

Terminal Symbol 

Explanation of Terminal Function 

R/L1, S/L2, T/L3 

AC line input terminals (3-phase) 

L/L1, N/L2 

AC line input terminals (1-phase) 

U/T1, V/T2, W/T3 

AC drive output terminals for connecting 3-phase 

induction motor 

+2/B1, B2 

Connections for Brake resistor (optional) 

+2/B1, +1 

Connections for DC Link Reactor (optional) 

 

Earth connection, please comply with local regulations.

  Connect these terminals via a non-fuse breaker or earth leakage breaker to 3-phase AC 

power (some models to 1-phase AC power) for circuit protection. It is unnecessary to 

consider phase-sequence. 

  It is recommended to add a magnetic contactor (MC) in the power input wiring to cut off 

power quickly and reduce malfunction when activating the protection function of AC 

motor drives. Both ends of the MC should have an R-C surge absorber. 

  Do NOT run/stop AC motor drives by turning the power ON/OFF. Run/stop AC motor 

drives by RUN/STOP command via control terminals or keypad. If you still need to 

run/stop AC drives by turning power ON/OFF, it is recommended to do so only ONCE 

per hour. 

  Do NOT connect 3-phase models to a 1-phase power source. 

 

  When the AC drive output terminals U/T1, V/T2, and W/T3 are connected to the motor 

terminals U/T1, V/T2, and W/T3, respectively, the motor will rotate counterclockwise (as 

viewed on the shaft end of the motor) when a forward operation command is received. 

To permanently reverse the direction of motor rotation, switch over any of the two motor 

leads.