Technical Specifications

FAQ

1. What is the main function of the Schneider ATS490C11Y soft starter?

The Schneider ATS490C11Y is an Altivar Soft Starter ATS490 designed to provide controlled starting and stopping of three-phase asynchronous motors. Instead of applying full line voltage immediately, it progressively controls the motor’s electrical conditions during acceleration and deceleration. Torque control helps reduce mechanical stress and starting current, which is particularly useful for industrial machinery with high inertia or demanding starting characteristics. The ATS490C11Y supports both in-line and inside-delta motor connections and includes functions such as internal bypass, motor thermal protection, monitoring, communication, and Safe Torque Off. It is intended for process and infrastructure applications where controlled motor operation and system availability are important.

2. What motor power can the ATS490C11Y handle?

The applicable motor power depends on supply voltage, connection method, and duty classification. For in-line connection, the ATS490C11Y has a rated operational current of 110 A for normal-duty applications and 88 A for heavy-duty applications. At 400 V, typical motor ratings are up to 55 kW for normal duty and 45 kW for heavy duty. At 690 V, the corresponding ratings can reach 90 kW and 75 kW. At 230 V, the typical ratings are 30 kW for normal duty and 22 kW for heavy duty. The actual motor selection should always be based on the motor nameplate current, starting requirements, load characteristics, operating cycle, and the applicable Schneider Electric sizing tables rather than motor power alone.

3. What supply voltage does the ATS490C11Y support?

The ATS490C11Y supports a three-phase AC supply voltage from 208 V to 690 V, with a permitted voltage tolerance of approximately -15% to +10%. The specified supply frequency range is 50–60 Hz, with a frequency tolerance of -20% to +20%. This wide voltage range allows the soft starter to be used in various industrial motor-control systems. Before commissioning, the incoming voltage, frequency, phase sequence, protective devices, and motor connection should be checked. The control supply is separate from the main power circuit and requires 110–230 V AC at 50–60 Hz.

4. How does the ATS490C11Y reduce motor starting stress?

The ATS490C11Y uses controlled semiconductor switching and torque control to regulate motor acceleration rather than applying full supply conditions immediately. The starting current can be limited within a configurable range of 150–700% of the rated operational current, with a maximum setting of 5 × Ie. By controlling the acceleration process, the soft starter can reduce electrical current peaks and mechanical shock transmitted through the motor shaft and driven equipment. This is especially useful for pumps, fans, compressors, conveyors, and other machines where abrupt starting can cause belt tension, coupling stress, pressure surges, or excessive demand on the electrical supply.

5. What communication functions are available on the ATS490C11Y?

The ATS490C11Y supports Modbus Serial as well as Modbus TCP and EtherNet/IP communication. The serial interface uses a two-wire RS-485 physical connection, while Ethernet communication uses 100BASE-TX through an RJ45 interface. Modbus Serial transmission rates range from 4.8 to 38.4 kbps, with configurable data formatting and addresses from 0 to 247. These communication functions allow the soft starter to exchange operating status, measurements, alarms, diagnostic information, and control commands with PLCs, HMIs, SCADA systems, and industrial networks. During commissioning, communication parameters and network addressing should be configured consistently with the automation system.

6. What protection functions are included in the ATS490C11Y?

The ATS490C11Y provides a broad range of protection functions for both the motor and the soft starter. These include main supply phase-failure protection, motor thermal protection, motor overload and underload monitoring, excessive acceleration-time protection, motor phase-loss detection, line phase-reversal protection, and external motor thermal protection. Motor thermal protection is based on Class 10E characteristics. The device can also detect conditions such as short circuits between a motor phase and earth. These functions help reduce the risk of damage caused by abnormal electrical or mechanical conditions, but appropriate upstream short-circuit protection and system-level safety measures are still required.

7. What is the purpose of the internal bypass in the ATS490C11Y?

The internal bypass allows the soft starter to bypass its main power semiconductor switching stage once the motor has successfully reached the appropriate operating condition. During starting, the semiconductor power stage controls the motor acceleration. After the starting process is completed, the internal bypass can reduce the continuous losses associated with the power electronics during steady-state operation. This can improve thermal performance and operating efficiency. The bypass is managed as part of the soft starter’s control architecture, so it should not be treated as a simple external contactor replacement. Proper configuration and wiring are important to ensure reliable operation during both starting and normal running conditions.

8. What should be checked if an ATS490C11Y fails to start a motor?

Troubleshooting should begin with the incoming three-phase supply and the 110–230 V AC control supply. Verify that all phases are present, the motor is correctly connected, and the soft starter is receiving the required start command. Check the motor rated current and other operating parameters, because incorrect configuration can cause protection functions to operate during startup. If the device reports phase loss, overload, excessive acceleration time, or thermal protection, investigate the corresponding electrical and mechanical conditions before replacing the unit. For network-controlled installations, verify the Modbus or Ethernet communication parameters, addressing, wiring, and control commands. If the motor repeatedly trips during acceleration, inspect the load torque, motor condition, starting-current limit, acceleration settings, operating cycle, and thermal condition of the soft starter.