SCHEDULE TYPE:
PROJECT:
ENGINEER:
CONTRACTOR:
DATE
B SERIES
SUPERSEDES DRAWING NO.
7 - 20 - 07
FD - ACC
12 - 4 - 02
MLS-300-2
Nailor Industries Inc. reserves the right to change any information concerning product or pricing without notice.
Dimensions are in inches (mm).
APPLICATION:
• The MLS-300 Position Indicator Package operates as a function
of the damper blade position and provides the ability to remotely
indicate damper blade position.
• The MLS-300 incorporates two SPDT switches and provides a
positive open or closed signal when used in conjunction with
remote indicator lights. MLS-300’s are used in active smoke
control management systems to positively indicate the status of
all combination fire/smoke and smoke dampers in the building.
• The MLS-300 is available only as a factory installed option on
combination fire/smoke and smoke dampers.
• The MLS-300 may also be used to provide a stop/start circuit
for remote fans or to signal alarms.
Position Indicator Microswitch Data:
Switch Type: Single Pole double throw (2)
15 Amps, 1/3 HP, 125, 250 Vac or 24 Vdc.
1/2 Amp, 125 Vdc. 1/4 Amp, 250 Vdc.
Standard Mounting:
MS1
is damper open signal.
MS2
is damper closed signal.
Non-Standard Mounting:
Important:
Installer must double check continuity of
MS1 and MS2 before wiring to determine which
switch signals the damper’s open or closed position.
EXTERNAL RIGHT HAND MOUNTING: FRONT VIEW (LESS COVER)
COVER
A
A
2 7/8" (73)
3" (76)
4 1/8" (105)
MS-2
MS-1
BLUE
YELLOW
SECTION A - A
JACKSHAFT /
DRIVESHAFT EXTENSION
CONDUIT
CONNECTION
DUCT OR
SLEEVE
13/16"
(21)
JACKSHAFT
MOUNTING BRACKET
1
6
7
5
4
3
2
3
NAILOR INDUSTRIES INC.
MLS-300
L2
L1
CLOSED
(RED LIGHT)
OPEN
(GREEN LIGHT)
MS2 DAMPER CLOSED
MICROSWITCH
BLU
BLU
YEL
YEL
MS1 DAMPER OPEN
MICROSWITCH
REMOTE CONTROL
STATION
(BY OTHERS)
MOUNTED ON DAMPER
(FACTORY WIRING TERMINATES
AT SPLICE POINTS INDICATED
INSIDE SWITCH BOX)
Typical Combination Fire / Smoke Damper
Installation With UL Listed Actuator
Description:
1. Electrical Junction Box (and EP switch with pneumatic
actuator[s])
2. ERL 165, 212, 250, 350°F Electric Resettable Link
(Heat Sensor)
3. Position indicator package
4. Actuator (pneumatic illustrated).
5. Silicone Tubing or Flexible Conduit
6. Over-Center Knee Lock
7. Jackshaft
POSITION INDICATOR PACKAGE
FOR COMBINATION FIRE / SMOKE, SMOKE AND
CONTROL DAMPERS
MODEL: MLS-300. For use with GGD221/121 (electric)
and 331-2961 / 3060 (pneumatic) actuators
