The ABB ACH550 is a variable frequency drive (VFD) designed for controlling the speed of AC motors. It is a popular choice for various industrial applications such as pumps, fans, compressors, and conveyors. The VFD is equipped with a bypass function that allows the motor to run at full speed in case of VFD failure or maintenance. This article will focus on the bypass control wiring diagram of the ABB ACH550 VFD.
What is a Bypass Control Wiring Diagram?
A bypass control wiring diagram is a schematic drawing that shows the electrical connections between the components of a VFD bypass system. It includes the wiring of the bypass contactor, the motor starter, and the VFD, as well as the interlocks, control switches, and signal devices. The bypass control wiring diagram is essential for the proper installation and operation of the VFD bypass system.
Components of the ABB ACH550 Bypass Control Wiring Diagram
The ABB ACH550 bypass control wiring diagram includes the following components:
| Component | Description |
|---|---|
| Bypass Contactor | A contactor that connects the motor directly to the power source when the VFD is bypassed. |
| Motor Starter | A starter that starts and stops the motor, and protects it from overloads and faults. |
| VFD | A variable frequency drive that regulates the speed and torque of the motor. |
| Interlocks | Circuit breakers, fuses, and safety switches that prevent dangerous conditions or malfunctions. |
| Control Switches | Pushbuttons, selectors, and switches that enable the operator to control the VFD and the bypass system. |
| Signal Devices | Lights, horns, and displays that indicate the status and alarms of the VFD and the bypass system. |
Wiring Diagram of the ABB ACH550 Bypass Control System
The following is a simplified wiring diagram of the ABB ACH550 bypass control system:
| Component | Terminal | Description |
|---|---|---|
| Bypass Contactor | L1, L2, L3 | Three-phase power supply input |
| T1, T2, T3 | Three-phase motor output | |
| 13, 14 | Control coil input from VFD | |
| Motor Starter | L1, L2, L3 | Three-phase power supply input |
| T1, T2, T3 | Three-phase motor output | |
| 95, 96 | Overload relay input | |
| VFD | L1, L2, L3 | Three-phase power supply input |
| T1, T2, T3 | Three-phase motor output | |
| 24 | Control power supply input | |
| AI1-AI2 | Analog input for speed reference | |
| DI1-DI6 | Digital input for control and monitoring | |
| DO1-DO3 | Digital output for status and alarms |
Note: The actual wiring diagram may vary depending on the specific model, options, and application of the ABB ACH550 VFD.
FAQ
Q: What is a bypass function in a VFD?
A: A bypass function in a VFD is a feature that allows the motor to run at full speed even if the VFD is not working or is undergoing maintenance. The bypass function is typically achieved by using a bypass contactor that directly connects the motor to the power source.
Q: Why do I need a bypass control wiring diagram?
A: You need a bypass control wiring diagram to properly install and operate the VFD bypass system. The wiring diagram shows the electrical connections between the components of the bypass system and ensures that the system is safe and reliable.
Q: Can I modify the wiring diagram of the ABB ACH550 bypass control system?
A: Modifying the wiring diagram of the ABB ACH550 bypass control system may void the warranty and cause the system to malfunction or even fail. If you need to modify the wiring diagram, consult ABB or a qualified technician first.
Q: What are the benefits of using a VFD?
A: Using a VFD can provide several benefits such as energy savings, improved process control, reduced motor wear and tear, and noise reduction. A VFD can also enable soft starting and stopping of the motor, which can enhance the longevity and efficiency of the motor and the driven equipment.
Q: What are the common applications of the ABB ACH550 VFD?
A: The ABB ACH550 VFD is commonly used in various industrial applications such as pumps, fans, compressors, conveyors, mixers, and other motor-driven equipment that require speed control and energy efficiency.
