Honeywell SERIES COMMUNICATING TB7600 - Manual (Page 20)

TB7600 SERIES COMMUNICATING RTU/HEAT PUMP THERMOSTATS
62-2016—01 20
Table 17. Additional Configuration Parameters for Economizer Models
Configuration
parameters
Significance
Default value Adjustments
Chngstpt Changeover setpoint
Default value = 55 F (13.0 C) In Cooling mode.
The outside air temperature value at which the cooling will be
switched over from mechanical (compressor) to free cooling
(economizer)
14 F to 70 F (-10.0 C to 21.0 C)
min pos Minimum position
Default value = 0% Outside air damper minimum position.
Will be active only when fan is on (G terminal) and the internal or
remote scheduling is in occupied mode.
When internal or remote scheduling is in unoccupied mode and/
or fan is off, minimum position will be set to 0%
0 to 100% = 0 to 10 Vdc output range
C mech Mechanical cooling allowed
Default value = Off In Cooling mode.
Allows the operation of the mechanical cooling if the free cooling
(economizer) cannot maintain the cooling setpoint.
Off Typically applies when the MS (mixed air temperature
sensor) is installed after the mechanical cooling refrigeration
coils. In this case, mechanical cooling will never operate at the
same time as free cooling.
On Typically applies when the MS (mixed air temperature
sensor) is installed before the mechanical cooling refrigeration
coils in the mixing plenum. In this case, mechanical cooling is
allowed when the free cooling (economizer operation) cannot
maintain the cooling setpoint.
Off or On
mix stpt Mixed air setpoint
Default value = 55 F (13.0 C) Free cooling mixed air setpoint when economizer mode is
enabled.
50 F to 90 F (10.0 C to 32.0 C)
MS dis Display mixed air temperature Economizer model only, only if sensor is installed.
Used as diagnostic/service help to troubleshoot and diagnose
economizer operation.
Outside air
percentage 0% 5% 10% 15% 20% 25% 30%
Setting for 0-10
Vdc Actuator 0% 5% 10% 15% 20% 25% 30%
Setting for 2-10
Vdc Actuator 0 to
20% 24% 28% 32% 36% 40% 44%
62-2016.fm Page 20 Thursday, April 14, 2011 1:40 PM