ALM RECTANGULAR MULTI-BLADE ALUMINIUM DAMPER Characteristics: A rectangular multi-blade damper with backward blades with a narrow profile intended for airflow control in small crosssection ducts. Controlled manually or by an electric actuator. Intended Use ALM dampers are intended for installation in ventilation and air conditioning systems for airflow regulation. They can be used together with recuperators (split “bypass” dampers) as well. ALM dampers are not suitable for operating as shut-off dampers. The device holds hygiene certificate no. HK/K/0841/02/2017. Operating temperature: -20 °C to +90 °C, (+50 °C for the actuator version). The aluminium profile shape is protected as a utility design and was registered with the Patent Office of the Republic of Poland. Manufacturing Versions Drive: Figure 1. ALM damper dimensions. ALM dampers are made of four types of hardened aluminium profiles: vertical housings, horizontal housings, blades (louvres) and the shelves for actuators. Damper louvres are connected with bearings and gears made of polypropylene (PP). The drive system is embedded in the profile (vertical housing). The PVC gasket is a seal between the damper blades. Figure 2. ALM damper blade. Standard dimensions of ALM dampers: T1 Damper with an actuator T2 Damper with a manual mechanism T3 Damper with an extended axle (for the actuator installation) Width A = 100÷600 mm (1 mm interval), Height B = 105÷605 mm (50 mm interval). Due to the width of the blade, the recommended height is B = n x 50 + 5, where n is the number of the blades. It is possible to make the damper another height (1 mm interval), with a masking frame covering the clearance partially. If it is necessary to use a damper larger than 600 x 605 mm, a combined damper consisting of two smaller dampers is made. The dampers have independent driving axles (two separate manual mechanisms or actuators on opposite sides). Rectangular multi-blade aluminiu

Table 1. Types of actuators and the net surface area for the ALM damper in a fully open position. The given actuator types can be used in several variants differing in communication and supply voltage. Pressure loss for a custom-height damper (with a masking frame covering the clearance partially) is comparable to the pressure loss for the nearest smaller standard height read from Chart 1.

Table 3. Approximate weight of ALM dampers. * Optional values - if not specified, the default values will be used “additionally provide: actuator manufacturer (Siemens/Belimo); supply voltage (24 V or 230 V), safety functions (with or without spring return), operation of the return spring (spring closes the damper or spring opens the damper), type of control (close/open, 3-point, analog), whether the actuator is to have auxiliary contacts.