M9220-Bxx-3 On/Off Electric Spring Return Actuators Installation Guide
9
Tandem Operation
The tandem configuration provides twice the
running and spring return torque of a single actuator, or
354 lb
in (40 N
m). The two actuators mounted in
tandem using the M9000-158 Tandem Mounting Kit
operate in exact synchronization, causing the load to
be split evenly between each actuator.
Use two actuators from the same model type for
tandem operation. BGx models used in the tandem
configuration are wired in parallel.
Note:
Manual override does not function after the
actuators configured for tandem operation are mounted
to a damper shaft.
Auxiliary Switches (BxC Models)
The BxC models include two integral auxiliary switches
with a switch adjuster accessible on either face of the
actuator (as illustrated in Figure 2 and Figure 3). The
nominal factory setting for Auxiliary Switch No. 1 is
11° closing, and the nominal factory setting for Auxiliary
Switch No. 2 is 81° opening (relative to a 0 to 90°
rotation range). See the
for the auxiliary switch ratings.
The switch point of Auxiliary Switch No. 1 is fixed. The
switch point of Auxiliary Switch No. 2 is independently
and continuously adjustable from 25 to 95°. See
Figure 11 and use the method in the following example
for the most accurate positioning of Auxiliary Switch
No. 2.
To change the switch point of Auxiliary Switch No. 2,
proceed as follows:
1. Position the actuator in the full spring return
position.
Note:
Auxiliary Switch No. 2 is factory set to trip
when the actuator reaches the 81° position.
2. Rotate the switch adjuster until it points to the
desired switch point.
3. Connect Auxiliary Switch No. 2 to a power source
or an ohmmeter, and apply power to the actuator.
The actuator moves to the fully open position and
holds while power is applied.
4. Observe the switch point. If required, repeat
Steps 2 and 3.
Repairs and Replacements
A number of replacement parts are available; see
Table 1 for more details. If the M9220-Bxx-3 On/Off
Electric Spring Return Actuator fails to operate within
its specifications, replace the unit. For a replacement
electric actuator, contact the nearest
Johnson Controls
®
representative.
!
WARNING: Risk of Electric Shock.
Disconnect the power supply before making
electrical connections. Contact with
components carrying hazardous voltage can
cause electric shock and may result in severe
personal injury or death.
AVERTISSEMENT : Risque de décharge
électrique.
Débrancher l'alimentation avant de réaliser
tout branchement électrique. Tout contact
avec des composants conducteurs de
tensions dangereuses risque d'entraîner une
décharge électrique et de provoquer des
blessures graves, voire mortelles.
Figure 11: Switch Point Settings
A
FI
G
:s
wp
nt
Switch
Adjuster
