Description
FOR THE PRECISE CONTROL OF CONSTANT VOLUME FLOW RATES
Circular self-powered volume flow controllers for the control of supply air or extract air in constant air volume systems
- Volume flow rate can be set using an external scale, no tools required
- High control accuracy
- No on-site test measurements required for commissioning
- Suitable for airflow velocities of up to 2360 ft/min
- Any installation orientation; maintenance-free
- Casing air leakage to EN 1751, class C
Optional equipment and accessories
- Acoustic cladding for the reduction of case-radiated noise
- Secondary silencer Type CA or CS for the reduction of air-regenerated noise
- Hot water heat exchanger Type WL and electric air heater Type EL for reheating the airflow
- Actuator: B50 24 V AC/DC, 3-point (min/max)
- Actuator factory-mounted on CAV controller but can be retrofitted in the field
Application
- Circular CONSTANTFLOW CAV controllers of Type RN for the precise supply air or extract air flow control in constant air volume systems
- Mechanical self-powered volume flow control without external power supply
- Simplified project handling with orders based on nominal size
- Volume flow rate setpoint can be set on external scale
Special features
- Min / Max setpoint position can be set on site with mechanical stops
- High volume flow rate control accuracy
- Any installation orientation
Construction
- Galvanized sheet steel
Parts and characteristics
- Ready-to-commission controller
- Damper blade with low-friction bearings
- Bellows that acts as an oscillation damper
- Cam plate with leaf spring
- Scale with pointer to set the volume flow rate setpoint
- Aerodynamic function testing of each unit on a special test rig prior to shipping
- Correct operation even under unfavorable upstream conditions (1.5 D straight section required upstream)
Attachments
- Actuator: B50 24 V AC/DC, 3-point (min/max)
- Min / Max setpoint position can be set on site with mechanical stops
Accessories
- Lip seals on both ends (factory fitted)
Useful additions
- Secondary silencer Type CA or CS
- Heat exchanger Type WL
- Electric air heater Type EL
Construction features
- Circular casing
- Spigot suitable for circular ducts to EN 1506 or EN 13180
- Spigot with groove for lip seal
Materials and surfaces
Galvanized sheet steel construction
- Casing made of galvanized sheet steel
- Interior parts, nominal sizes 80 – 125: stainless steel 1.4301, nominal sizes 160 – 400: galvanized sheet steel
- Polyurethane bellows
- Plain bearings with PTFE coating
- Leaf spring made of stainless steel
Mineral wool
- To EN 13501, fire rating class A1, non-combustible
- RAL quality mark RAL-GZ 388
- Bio soluble and hence hygienically safe according to the German TRGS 905 (Technical Rules for Hazardous Substances) and EU directive 97/69/EC
Standards and guidelines
- Meets the hygiene requirements of VDI 6022
- Casing air leakage to EN 1751, class C
Maintenance
- Maintenance-free as construction and materials are not subject to wear
B50 Actuator: LM24A and LM24A-F
- Min/max switching of volume flow setpoint values of mechanical self powered volume flow controllers Type RN
- Supply voltage (AC) 24 V AC ± 20 %, 50/60 Hz
- Supply voltage (DC) 24 V DC ± 20 %
- Power consumption – when running 1 W
- Power consumption – when idle 0.2 W
- Power rating for cable sizing 1.5 VA
- Torque 5 Nm
- Running time for 90° 150 s
- Control input signal 1-wire control or 2-wire control (3-point)
- Connecting cable 3 × 0.75 mm², 1 m long
- IEC protection class III (protective extra-low voltage)
- Protection level IP 54
- EC conformity EMC to 2014/30/EU, RoHS 2011/65/EU
- Operating temperature –30 to 50 °C
- Weight 0.5 kg
- Mechanical stops for setting the volume flow rate setpoints
- Positive lock connection with damper blade shaft
- Release button to allow for manual operation
Commissioning
- Set the mechanical stops according to the minimum and maximum volume flow rates
- Change the direction of rotation if necessary, using the switch, to switch between min and max
Literature
