Honeywell s User Manual

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MS4120F; MS4620F,S; MS8120F,S; S2024-F; S20230-F FAST-ACTING, TWO-POSITION ACTUATORS
7
63-2584—7
OPERATION
The actuators are designed for use in Smoke Control Systems. 
If power fails, the actuator spring returns to the 0° position. The 
actuator mounts flush with the damper box. The actuator drives 
from 0° to 95° and spring returns back to 0°.
The actuators are operated by an spst two-position controller. 
When using an spst two-position controller, the actuator drives 
to the damper fully open position when controller contact 
makes and spring returns to the damper fully closed position 
when controller contact breaks. The actuator drops to holding 
power level on detection of stall, independent of hub position.
Cycling
The actuator and the internal spring are designed so that no 
special cycling during long-term holding is required. Honeywell 
recommends following all local, state, and national codes for 
periodic testing of the entire smoke control system. Refer to 
National Fire Protection Association (NFPA) National Fire 
Codes
®
: NFPA90A, NFPA92A, and NFPA92B for your 
application.
Auxiliary Switches
Some models include auxiliary switches (see Table 1).
SPST Switches (Table 5)
See Fig. 6 through 8 for SPST auxiliary switch wiring.
Table 5. SPST Auxiliary Switch Operation.
NOTE: Both sets of contacts are open when the actuator is 
between 7° and 85°.
SPDT Switches (Fig. 11)
See Fig. 9 through 11 for SPDT auxiliary switch wiring.
Fig. 11. SPDT auxiliary switch operation.
Switch
Wire 
Color
Makes
Breaks
(degrees from fully closed position)
blue
less than 7
greater than 7
85°
yellow
greater than 85
less than 85
BLACK/BLUE
BLACK/RED
BLACK/YELLOW
BLACK/BLUE
BLACK/RED
BLACK/YELLOW
LESS 7°
MORE 7°
GRAY/BLUE
GRAY/RED
GRAY/YELLOW
GRAY/BLUE
GRAY/RED
GRAY/YELLOW
LESS 85°
MORE 85°
7° SWITCH
85° SWITCH
M20679B