Belimo AF Series Manual

AF24 (-S) US
On-off, Spring Return Fail-Safe, 24 V
LISTED
U L
94D5
TEMP. IND &

.
REG. EQUIP
Technical Data AF24 (-S) US
Power supply 24 VAC ± 20% 50/60 Hz
24 VDC ± 10%
Power consumption running: 5 W; holding: 1.5 W
Transformer sizing 10 VA (class 2 power source)
Electrical connection 3 ft, 18 GA appliance cable
1/2" conduit connector
Electrical protection auxiliary switches are double insulated
Overload protection electronic throughout 0° to 95° rotation
Angle of rotation 95°, adjustable 35 to 95° w/ ZDB-AF2
Torque 133 in-lb [15 Nm] constant
Direction of rotation reversible with CW/CCW mounting
Position indication visual indicator, 0° to 95° (0° is spring
return position)
Manual override 3mm hex crank (shipped w/actuator)
Auxiliary switches 2 x SPDT 7A (2.5A) @ 250 VAC, UL listed
one set at +5°, one adjustable 25° to 85°
Running time 150 sec. constant, independent of
load, spring return < 20 sec
Humidity 5 to 95% RH non-condensing
Ambient temperature -22°F to +122°F [-30°C to +50°C]
Storage temperature -40°F to +176°F [-40°C to +80°C]
Housing NEMA type 2 / IP54
Housing material zinc coated steel
Agency listings UL 873 listed, CSA C22.2 No. 24 certified
Noise level max. 45 dB (A)
Servicing maintenance free
Quality standard ISO 9001
Weight 6.0 lbs (2.7 kg.)
20
Torque min. 133 in-lb, for control of air dampers
Application
For on-off, fail-safe control of dampers in HVAC systems.
Actuator sizing should be done in accordance with the damper
manufacturer's specifications. Control is on-off from an auxil-
iary contact, or a manual switch.
The actuator is mounted directly to a damper shaft up to 1.05"
in diameter by means of its universal clamp. A crankarm and
several mounting brackets are available for applications where
the actuator cannot be direct coupled to the damper shaft.
Operation
The AF series actuators provide true spring return operation for
reliable fail-safe application and positive close off on air tight
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dampers. The spring return system provides consistent torque
to the damper with, and without, power applied to the actuator.
The AF series provide 95° of rotation and are provided with a
graduated position indicator showing 0° to 95°. The AF has a
unique manual positioning mechanism which allows the set-
ting of any damper position within its 95° of rotation. The AF
series actuators are shipped at +5° (5° from full fail-safe) to
provide automatic compression against damper gaskets for
tight shut-off. When power is applied to the AF series, the
manual mechanism is released. The actuators will now try to
close against the 0° position during its normal control opera-
tions. The manual override can also be released physically by
the use of a crank supplied with the actuator.
The AF uses a brushless DC motor which is controlled by an
Application Specific Integrated Circuit (ASIC). The ASIC moni-
tors and controls the actuator's rotation and provides a digital
rotation sensing function to prevent damage to the actuator in
a stall condition. The actuator may be stalled anywhere in its
normal rotation without the need of mechanical end switches.
The AF24-S US version is provided with 2 built in auxiliary
switches. These SPDT switches are provided for safety inter-
facing or signaling, for example, for fan start-up. The switching
function at the fail-safe position is fixed at +5°, the other switch
function is adjustable between +25° to +85°.
Dimensions
K4-2 US (supplied)
1/2" Centered
(Default)
3/4" Centered
(Field Selectable)
1.05" Centered
(Field Selectable)
K4-1 US (optional)
3/4" to 1.05"
Adjustable
K4 US (optional)
3/8" to 3/4"
Adjustable
[All numbers in brackets are in millimeters.]
0.65" [16.5]
0.19" [5]
10.59" [269]
0.39" [10]
2.64"
5.85" [148.5]
[67]
0.35" [9]
0.26" [6.5]
1.97"
[50]
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