Submittal Sheet

800-543-9038 USA 866-805-7089 CANADA 203-791-8396 LATIN AMERICA
1
03
T
orque min. 35 in-lb, for control of air dampers
A
pp
l
i
cat
i
o
n
F
or proportional modulation of dampers in HVAC systems. Actuator sizing should be
d
one in accordance with the damper manufacturer’s specifications.
T
he actuator is mounted directly to a damper shaft from 3
/
8” up to 1
/
2” in diameter
by
means of its universal clam
p
, 1/2” shaft centered at deliver
y
. For shafts u
p
to 3/4”
u
se K6-1 accessory. A crank arm and several mountin
g
brackets are available for
a
pplications where the actuator cannot be direct coupled to the damper shaft
.
T
he actuator o
p
erates in res
p
onse to a 2 to 10 VDC, or with the addition of a 500W
r
esistor, a 4 to 20 mA control input from an electronic controller or positioner. A 2 to
1
0 VDC feedback si
g
nal is provided for position indication or master-slave applications.
Op
eratio
n
T
he LF series actuators provide true sprin
g
return operation for reliable fail-safe
a
pplication and positive close-off on air tight dampers. The spring return system
p
rovides consistent tor
q
ue to the dam
p
er with, and without,
p
ower a
pp
lied to the
actuato
r
.
T
he LF series provides 95° of rotation and is provided with a
g
raduated position
i
n
di
cator s
h
ow
i
ng 0 to 95°.
T
he LF24-SR (-S) US uses a brushless DC motor which is controlled by an Application
S
pecific Inte
g
rated
C
ircuit
(
A
S
I
C)
and a microprocessor. The microprocessor provides
the intelli
g
ence to the A
S
I
C
to provide a constant rotation rate and to know the
a
ctuator’s exact fail-safe
p
osition. The ASIC monitors and controls the brushless DC
motor’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
r
otation without the need o
f
mechanical end switches. Power consumption is reduced
i
n holdin
g
mode
.
T
he LF24-SR-S US version is provided with one built-in auxiliary switch. This SPDT
s
witch is provided
f
or sa
f
ety inter
f
acing or signaling,
f
or example,
f
or
f
an start-up. The
s
witching function is adjustable between 0° and 95°. The auxiliary switch in the
L
F24-SR-S US is double insulated so an electrical
g
round in not necessary
.
Dimensions (Inches [mm])
0.39" [10]
7.67" [195]
3.66" [93]
1.93"
[49]
6.10" [155]
3.15" [80]
3.86"
[98]
0.256" [6.5]
0.98"
[25]
4.92" [125]
0.79"
[20]
0.5"
[12.7]
0.71" [18]
0.74" [18.7]
2.24"
[57]
3.23" [82]
0.25" [6.3]
Standard:
3/8" to 1/2"
3/8" to 7/16"
Optional
1/2" to 3/4"
w/K6-1
accessory
D0
1
0
LF24-
S
R
(
-
S)
U
S
Proportional, Sprin
g
Return, 24 V for 2 to 10 VDC or 4 to 20 mA Control Si
g
na
l
Technical Data LF24-SR(-S) US
P
ower supp
l
y 24 VA
C
± 20% 50
/
60 H
z
24 VDC ± 10%
P
ower consum
p
tio
n
r
unnin
g
2.5 W
holding
1 W
Trans
f
ormer sizin
g
5
VA
(
c
l
ass 2 power source
)
E
lectrical connectio
n
L
F24-SR US 3
f
t, plenum rated cabl
e
1/2” conduit connecto
r
L
F24-
S
R-
S
U
S
3 ft, 18
G
A appliance cables
(
2
)
1
/
2” conduit connector
s
Overload
p
rotectio
n
electronic throu
g
hout 0 to 95° rotation
I
n
p
ut im
p
edanc
e
100 k
Ω
(
0.1 mA
)
, 500
Ω
A
ngle o
f
rotatio
n
max. 95°, a
dj
ust. w
i
t
h
mec
h
an
i
ca
l
sto
p
Torqu
e
35 in-lb [4 Nm]
Direction o
f
rotatio
n
sprin
g
reversible with cw/ccw mountin
g
mo
t
o
r
reversible with built-in switch
Pos
iti
o
n in
d
i
ca
ti
on
visual indicator
,
0° to 95
°
(
0°
i
s spr
i
n
g
return pos
i
t
i
on
)
R
unnin
g
tim
e
m
o
t
or
150 sec constant, inde
p
endent of loa
d
(
nominal
)
sprin
g
< 25 sec @-4°F to 122°F
[
-20°C to 50°C
]
< 60 sec
@
-22°F
[
-30°
C]
H
umidit
y
5 to 95% RH non-condensin
g
A
mbient temperatur
e
-22°F to 122°F
[
-30°C to 50°C
]
Stora
g
e temperatur
e
-40°F to 176°F
[
-40°C to 80°C
]
H
ous
i
n
g
NEMA type 2
/
IP54
H
ousin
g
materia
l
zin
c
coa
t
ed
m
e
t
al
Ag
ency listin
gs
cULus acc. to UL 873 an
d
C
AN
/CS
A
C
22.2 No. 24-93
N
oise level
(
max
)
r
unnin
g
< 30 db
(
A
)
s
pr
i
n
g
retur
n
62
dB
(A)
Servicin
g
m
a
int
e
n
a
n
ce
f
r
ee
Qualit
y
standar
d
I
SO
900
1
W
e
i
g
ht
LF24-
S
R U
S
3.1 lbs (1.40 kg)
LF24-
S
R-
S
US
3.2
lb
s
(
1.45
kg)
LF24-
S
R-
S
U
S
A
uxiliary switc
h
1 x
S
PDT 3A (0.5A)
@
250 VA
C
, UL Approve
d
adjustable 0° to 95° (double insulated
)
M40024 - 05/10 - Subject to change. © Belimo Aircontrols (USA), Inc.