This new model fills in the gap at 300-350 hp in the SJ700 series, which now completely covers the range from ½ to 600 hp.
The SJ700 significantly expands on the performance, capabilities and functions of its predecessor, the SJ300. Hitachi reasserts its technological leadership with an improved vector control algorithm and auto-tuning function that enables the open-loop SJ700 (SLV) to develop more than 200% starting torque at 0.3 Hz. Using Hitachi’s unique "0 Hz Domain" open-loop control mode, the SJ700 can develop 150% torque near 0 Hz, ideal for vertical lift applications. In closed-loop mode with encoder feedback, the SJ700 performance is unmatched, delivering in excess of 100% torque at 0 Hz.
Another major new element in the SJ700 is Hitachi’s EzSQ (Easy Sequence) built-in programming function. It’s like having a PLC inside the inverter! In many cases, the need for a separate PLC can be eliminated. The user develops EzSQ programs on a PC, and then downloads them to the inverter using the simple-to-use configuration/programming software provided at no charge.
The SJ700 can deliver true servo-like position control when mated with a general-purpose induction motor and encoder, offering a low-cost motion control alternative. The SJ700, given a position command, speed command, and acceleration/deceleration times, can move the motor shaft from position A to position B following the defined profile and then maintain the shaft in "servo lock" status.
Hitachi has added other new features into the SJ700, such as patented micro-surge voltage suppression (to protect the motor winding insulation), advance trip avoidance functions, configurable sink/source logic on I/O, built-in dynamic braking circuit in models up to 30 hp (22 kW), built-in EMC filter up to 75 hp (55 kW).
The SJ700 also includes built-in RS485 Modbus/RTU communication, and options for other communications networks, such as Ethernet Modbus/TCP, DeviceNet, Profibus and LonWorks. Others, such as Ethernet/IP are in the works. The SJ700 can be configured via the front-mounted keypad or using Hitachi’s ProDrive PC-based software.
Designed to be a product for the global market, the SJ700 carries CE, UL, cUL and c-Tick marks, and is RoHS compliant.
Hitachi America, Ltd. - www.hitachi.us
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