R81EAA Technical Bulletin 3
Make wiring connections using
copper conductors only and in
accordance with the National
Electrical Code and local
regulations. Refer to the typical
wiring diagram for selected hookup.
All splices are to be made in
junction boxes using approved
solderless connectors, or by
soldering and then taping the
connections. All splicing and
excess wiring must be located
outside of the motor actuator wiring
compartment. If desired, a
standard electrical box can be
added to the wiring compartment of
the motor actuator. (See Fig. 3.)
When more than one Series M100
motor actuator, with the R81EAA
installed, is powered from the same
24 VAC power source, polarity
must be maintained; connect all T
2
terminals to the same side of the 24
VAC supply.
To avoid potential miswiring,
separate transformers are
recommended. When slaving
motor actuators with the number
10 terminals connected together,
separate transformers must be
used. Never simultaneously
parallel terminals 10 and T
1
. If an
existing 24 VAC power supply is
available, Johnson Controls Y69
isolation transformer is
recommended. M100J motor
actuators may be slaved from the
R81EAA/M100 using the “X”
terminal and a common power
supply. (See Fig. 8.)
Adjustment
Set Point
The set point for the remote
sensor is located on the R81’s
terminal board and has a
calibrated dial that is adjustable
between 40 and 90
°
F (5 and
30
°
C). Should a remote set point
be desired, such as a room
ventilation control, turn the set
point knob counterclockwise to
its limit at the low temperature
end of the dial and set the
temperature at the T91BCA
thermostat or remote Y45BA-1
set point adjuster.
Proportional Band
The proportional band adjustment
is located on the cover mounted
circuit board. The proportional
band is adjustable between 2 and
20
°
F (1.1 and 11
°
C).
!
CAUTION: While narrowing
the proportional band is
usually desirable, too narrow
a proportional band may
result in poor control. The
proportional band must be
increased if the motor
actuator cannot maintain a
stable position when the
system is operating.
Instability causes the motor
actuator to oscillate (hunt).
Remote Minimum Position
Remote control of the outdoor
air dampers is desirable where
temporary additional ventilation
is required. For example, a
restaurant, conference room,
factory, or store may need to
have the air purged temporarily.
The “O.A. Minimum”
potentiometer is integral on the
cover mounted circuit board for
minimum position control. The
addition of a Y45AA-9 will allow
the building occupant to control
the minimum position from a
remote location. (See Fig. 6.)
Night Setback
During the “day” mode, the T26
night setback thermostat is locked
out of the heating circuit.
However, in the “night” position,
the T26 thermostat, with its lower
set point, will operate the heating.
Also, in the night position, cooling
will be entirely locked out and the
O.A. damper will be closed.
(Dampers close only with spring
return motor actuators.) When
supply power is cut to the
transformer, the spring return
motor actuator closes the damper.
(See Fig. 7.)
