The NSFTxx soft starters accelerate and decelerate motor loads smoothly, save energy and reduce system wear and tear. They interface with most (if not all) automation equipment in the market and are a favourite mechanical interface in many applications.
The NSFTxx soft starters are fully protected, digitally-controlled and programmable units. They are simple to install and are effectively employed in applications driving:
- Transport systems (conveyors, escalators, roller tables etc.) for low inertia loads,
- Pumps and compressors,
- Inelastic transmissions (gear trains, high-ratio belt systems etc.), and
- Fans and ventilators.
Main features of the line include:
- Generous x4 starting current and cooling circuit design provides for 60-555 A (starting, per phase), 10-90 HP/7.5-66 kW (at 3x400 V) loads. The employed 1600 VDC power circuit allows our soft starters to be used in up to 3x480 VAC systems.
- User selectable starting current limitation to control the acceleration torque.
- Complete and comprehensive electronic protection:
- Overcurrent: load current is monitored in each phase and the overload limit is set by the user.
- Undercurrent: to detect mechanical coupling problems (such as loose belts and uncoupled transmissions) and unloaded conditions (such as a dry pump).
- Over/Under-voltage: to protect against supply line problems.
- Phase sequence and integrity: to protect against dropped phase faults and wrong phase sequence after reconnection to the grid.
- Noise and line disturbances: protected against the high-voltage spikes and faults of the industrial environment.
- Internal temperature: to protect against cooling circuit failure, typically caused by a blocked fan or ventilation inlet/outlet.
- Individually powered, isolated, versatile two input user/control interface.
- Selection of fault handling, trigger/control type, profile, deceleration, starting value and duration, operation timer by DIP switch.
- Galvanically isolated bit outputs ("Idle", "Run", "By-pass", "Fault").
- Load current signal analog output.
- Overcurrent limit can also be set externally via the analog input.
- Small 24 VDC power supply to power a local sensor or other automation device.
- Installation-friendly, robust, space-saving "bookcase" style enclosure.
- Separate control circuit supply to enable separate/isolated power circuit functions and to prevent any power disruptions from affecting the unit's control and monitoring functions.
The individual model characteristics are summarized in the following table:
|NSFTxx line characteristics at 3x400 VAC|
|Motoring heat dissipation|
(worst case, no by-pass),
Other soft starter products of interest are:
Units above 90 HP and for non-standard or medium voltage applications are offered on a custom, per order basis.
- The BSxT Basic Soft Starter addresses simple and low cost applications such as hydraulic lift pumps and ventillation fans.
- The iSFT Intelligent Soft Starter Controller is recommended for more complex and demanding soft starting applications.
- The Solid State Relay Analog Controller can be used to start a single phase motor load.