Casing
The casing shall be constructed from self-supporting corrosion-resistant extruded aluminium section assembled with Aluminium corners and 25mm thick double skinned removable panels, manufactured from pre-galvanised steel, in-filled with a non-flammable mineral wool.
Motors
The IEC frame Motor shall be either AC Three phase multi-voltage IP55 TEFC or TEAO Foot / Flange mounted, wound for either (Delta) 230V/3Ph/50Hz or (Star) at 400V/3Ph/50Hz connection, suitable for speed control when used with a Variable Frequency Drive or EC single or three phase permanent magnet IE6 totally enclosed to IP55 with centralised control circuit for speed adjustment and Electronic protection against overload, over temperature and locked-rotor suitable for 50 and 60Hz supply.
Impellers
Impeller shall be a high efficiency backward curved EN-AW 5754 aluminium with a non-overloading power characteristic, dynamically balanced according to ISO1940 part 1.
Control
Units shall be suitable for use with Variable frequency drive or connection to a remote DC voltage: 2 to 10 VDC, DC current: 4 to 20 mA DC ¬ PWM: 10 to 95% ¬or potentiometer for speed control, dependent on model.
Design
The unit shall be designed and manufactured with procedures as defined in BS EN ISO 9001. Airside performance shall be tested to ISO 5801 and BS ISO 13347-1 (sound performance).