Centris - The FAIRFORD Medium Voltage Soft Starter
Centris is the fully featured medium voltage soft start motor controller from Fairford available in the range of 2.3 kV to 15 kV. Centris soft start motor controllers are designed to start AC motors in any fixed speed application. They provide maximum protection with ‘True Thermal Modelling’ while allowing smooth, stepless control of acceleration and deceleration. Centris guarantees power control and protection for your most important assets, vital in an unpredictable world.
Flexible control features and selectable ramping profiles are available to match any application so there is no need to compromise on power. Sealed NEMA 12/IP55 rated enclosures are standard as are built in 120v control power transformers, load-break/fault make disconnect switches, heavy duty SCR assemblies with ring transformer isolation, and line isolation vacuum contactors.
Rated at 500% for 60 seconds, Centris will never be the limiting factor in your application. Powerful sustained gate pulse ensures reliable SCR firing without reactors. High end motor protection, fully rated bypass contactor and fibre optically isolated means the Centris soft starter is the pinnacle of product development.
Peak performance and protection guaranteed from your critical medium voltage equipment, when your motors are protected and controlled by Fairford’s Centris Soft Starters.
Features & Benefits:
True Thermal Modelling
Monitors the motor for excessive thermal conditions due to starting, running and even ambient conditions.
Retentive Thermal Memory
For continuous overload protection even after a complete power loss. When power is restored, the Centris Soft Starter remembers the last thermal condition of the motor, observes the off time via a real-time clock and adjusts the thermal model accordingly.
Stores the thermal memory without the need for batteries.
True Time Thermal Tracking
Adjusts the thermal model for different cooling rates based on motor temperature, running state or power loss.
Dynamic Reset Response Reset
Is only allowed after the motor has sufficient thermal capacity for a successful restart.
Thermal Model Biasing
Adjusts for heating effects of phase current imbalance or optional RTD inputs.
Choose the level of overload protection.
Programmable Trip Classes
Selectable from IEC/NEMA Classes 5 – 30.
Dual Mode Protection
Separate trip curves for start and run modes (example: Class 20 for start, Class 10 for run).
Can be programmed and assigned to one of six built-in output relays.
Custom Trip Curve
Programmable based on the motor manufacturer’s data or it can use a “Learned Overload Curve” that reflects normal running condition with a programmable trip bandwidth.
Remote or Automatic Overload Reset
Can be activated for unattended operation
The following is an overview of technical specifications of the Fairford Centris product range:
|Type of Load||3-phase medium voltage AC induction or synchronous motors|
|AC Supply Voltage||2300, 3300, 4160, 6000/7200V, 11-15kV|
|VAC +10% to -15%, 50/60 Hz line voltages|
|HP Ratings||Up to 10,000 HP @ 7.2kV (1500 Amps)|
|Up to 20,000 HP @ 15kV (800 Amps)|
|Contact us for higher rating requirements|
|Overload Rating||AC53b 600-30-60m|
|BIL Rating||2300V – 7200V 60kV|
|11000 – 15000V (110kV)|
|Transient Voltage Protection||dv/dt circuits (1 per SCR pair)|
|Vacuum Bypass Contactor||Standard on all models, line start rated|
|Ambient Operating Conditions||0 – 50°C (82° F to 122° F)|
|5 – 95% relative humidity|
|0 – 3300 ft (1000m above sea level without derating)|
|Digital Control Unit (DCU)||Programmable keypad/operator with 2 lines x 20 character backlit LCD display|
|Status/Alarm LEDs (indicate: Power, Run, Alarm, Trip, Aux 1 – 8)|
|Auxiliary Contacts||Multiple Form C contacts rated 5A @ 250VAC|
|6 fully programmable relays (including fail-safe operation)|
|5 dedicated relays (fault, at-speed, etc.)|
|Programmable Features||Motor FLA, service factor, insulation class|
|Dual Ramp Adjustments – Two independent settings for:|
|– Initial Torque 0 – 100% of nominal torque, voltage or current|
|– Current Limit 200 – 600% of motor FLA|
|– Acceleration Time 1 – 120 seconds|
|Power Ramp Function|
|Three Custom Curves Via plotted torque/time axis points|
|Pump-Flex™ Deceleration 1 – 60 seconds with begin & end torque adj|
|Kick Start 0.1 – 2.0 seconds (10 – 100% voltage)|
|Tach Feedback (option) Closed loop speed ramp|
|Motor and Starter Protection||Electronic Overload Phase Loss|
|Phase Imbalance Phase Reversal|
|Short Circuit Detection Over / Under Current|
|Over / Under Voltage Shorted SCR / Shunt Trip|
|Starter Over-Temp Coast Down Lockout|
|Starts per Hour Lockout Time between starts|
|RTD Input (Option) Ground Fault (Option)|
|Enclosure||NEMA 12 with 3R optional|
|top and bottom entrance plates|
|11 gauge steel|
|ASA #61 gray powder coated paint|
|Communications||RS485 with Modbus RTU protocol|
To know more about Fairford Centris MV Softstarters please download the following product brochure: