2.3 Main Circuit 2.3.1 Main Circuit Connection Brake Resistor(Optional) BR Brake Unit (Optional) No fuse breaker (NFB) BUE R MC R(L1) + - U(T1) Motor CAUTION! Mains power terminals (R/L1, S/L2, T/L3) Connect these terminals (R/L1, S/L2, T/L3) 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.
Please make sure to fasten the screw of the main circuit terminals to prevent sparks which is made by the loose screws due to vibration. Please use voltage and current within the regulation shown in Appendix A. When using a GFCI (Ground Fault Circuit Interrupter), select a current sensor with sensitivity of 200mA, and not less than 0.1-second detection time to avoid nuisance tripping. For specific GFCI of the AC motor drive, please select a current sensor with sensitivity of 30mA or above. 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. Output terminals for main circuit (U, V, W) Terminals [+, -] for connecting brake resistor All VFD-EL series don’t have a built-in brake chopper. Please connect an external optional brake unit (BUE- series) and brake resistor. Refer to BUE series user manual for details. When not used, please leave the terminals [+, -] open.
Revision 2016/03, 6ELE, V1.14 2-7 Terminal Symbol Explanation of Terminal Function R/L1, S/L2, T/L3 AC line input terminals (1-phase/3-phase) U/T1, V/T2, W/T3 AC drive output terminals for connecting 3-phase induction motor +, - Connections for External Brake unit (BUE series) Earth connection, please comply with local regulations. The factory setting of the operation direction is forward running. The method to control the operation direction is to set by the communication parameters. Please refer to the group 9 for details. When it needs to install the filter at the output side of terminals U/T1, V/T2, W/T3 on the AC motor drive. Please use inductance filter.
Do not use phase-compensation capacitors or L-C (Inductance-Capacitance) or R-C (Resistance-Capacitance), unless approved by Delta. DO NOT connect phase-compensation capacitors or surge absorbers at the output terminals of AC motor drives. Use well-insulated motor, suitable for inverter operation.