Figure 2 - Mounting Dimensions for W7080A
W7082A, W7083A, W7084A
Units in Inch [mm In
brackets]
Nonspring Return Motors - M734J, M744D
have a solid
state balance relay, operate on 24 Vac, 50/60 Hr.
Spring Return Motors - M746G,K,L,P motors have solid-
state balance
relay, require separate 24 Vac, 50/60 Hz
power supplies.
Time Delay Relays - To improve stability of the system
and minimize energy use, five minute turn on time delays
should be added to all heating and cooling loads. These
relays should be wired between cooling and heating stage
switching outputs (W7080A Load Analyzer W7083A Electric
Heat Sequencer and 1953258 Fourth Stage Cooling Board)
and the heating and cooling equipment.
SYSTEM ACCESSORIES:
Transformers: AT20-20 VA; AT7240 VA; AT88-75 VA
4
Analyzer can also be used to power stage relays in the
W7083A Electric Heat Sequencer (if used). The M744
and M745 motors each require a separate transformer to
ensure electrical isolation. ‘NEVER GROUND THE
I
SECONDARY OF ANY TRANSFORMER USED TO
POWER ANY SYSTEM COMPONENT.
I
Q209A Minimum Position Potentiometer - Mounts direct-
iy on M734, M744, M745 motors; controls minimum open
position of damper.
Q605 Damper Linkage - Connects motor to damper.
in-
cludes motor crank arm.
Q618 Valve
Linkage - Connects Modutrol motor to
modulating hot or chilled water valves.
S963A Remote Mlnlmum PositIon Potentiometer
-
Provides remote manual control of minimum open position
of economizer motor.
Modulatlng
Water Valves - Use appropriate valve with
Super Modutrol motor and Q618 Linkage to provide propor-
tional control of hot or chilled water flow.
Compressor Ambient Lockout Thermostat - Use
with
direct expansion cooling system to prevent compressor
operation when outdoor air temperature falls below
economizer setpoint.
-
T675A Temperature Controller.
-
L6018C Temperature Controller.
Economizer Changeover Controller
- Holds economizer
at minimum position whenever outdoor air temperature or en-
thalpy is above controller setpoint.
-
H205A1038 or H205A1046 Enthalpy Controller.
-
T675A
Nlght Setback
- Provides heating setback of 6 to 22°F
[3.3 to 12.2°C]. Requires connection
of a 1% resistor and
S6005 Time Clock contact conncected between Terminals 3,
7 or 6;
and 5 of T7080A or T7080B Thermostat.
-
T675A
-
S43 Sail Switch
- Activates circuits when minimum airflow
is maintained in duct. Deactivates circuit below minimum
airflow.
1914448
Metal Cover - Designed to protect the W7080A,
W7081A, W7082A, W7083A and W7084A components when
mounted on open surface. Overall dimensions of units with
metal cover in place:
in. long,
in. wide,
in.
high [168.3 108.5 x 122.2 mm].