Trane Voyager RT-SVX17C-EN, Установка, эксплуатация и обслуживание

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Microelectronic Control Features
1. Anti short cycle timer (ASCT) function. Compressor op-
eration is programmed for 3 minutes of minimum “ON”
time, and 3 minutes of minimum “OFF” time. Enhances
compressor reliability, and ensures proper oil return.
2. Delay between stages timer function. When combined
with a standard Zone Sensor Module, the Reliatel Refrig-
eration Module (RTRM) provides a 10 second minimum
“ON” delay for compressor staging.
3. Built in Fan Delay Relay function for Constant Volume
Units. When the fan mode switch on the Zone Sensor
Module is set in the auto position, the RTRM provides in-
dividual supply fan timing sequences for each system in
heating and cooling. The RTRM provides different timing
sequences for Gas Heat units and Cooling only units.
4. Low ambient cooling to 0° F with Frostat™.
5. Built in electric heat staging, provides a 10 second “ON”
delay between resistance heat stages.
6. Compressor cycle rate minimization, extends compres-
sor life expectancy. Minimizes damaging compressor in-
rush current, and guards against short cycling.
7. Economizer preferred cooling allows fully integrated
economizer operation with mechanical cooling if actually
needed.
On constant volume applications, a 3 minute delay al-
lows the RTRM to evaluate the rate of change in the
zone. If the zone temperature is dropping faster than ac-
ceptable parameters, the compressor(s) will not be al-
lowed to operate.
8. Free night setback allows the unit to enter an unoccupied
mode by simply shorting across terminals RTRM J6-11
and J6-12. The short can be achieved by a set of dry con-
tacts or a time clock. Once this short has been made the
unit will close the economizer dampers, go from continu-
ous fan to auto fan operation, and:
CV Unit w/Mechanical ZSM
if the unit has a valid cooling and heating setpoint, the
setup/setback is a minimum of 7°.
If the unit does not have both setpoints, the setup/setback is
0°.
If the unit has neither setpoint, the unoccupied cooling/heat-
ing setpoints will be 74°F/71°F.
This input is ignored if a conventional thermostat is used.
VAV unit w/o ICS or NSB
engerizes heating if the space temperature drops to 10
o
F
below the MWU setpoint but not less than 50
o
F
This option can not be used with programmable ZSM or
with an ICS
TM system.
9. Low pressure cutouts on all compressors have been
added to insure compressor reliability in low refrigerant
flow situations. The compressor(s) will lockout after four
consecutive low pressure control trips during the com-
pressor minimum 3 minute "on" time. The lockout will
have to be manual reset as explained in this document.
Economizer Operation with CV Controls
The control point for the economizer is designed to control
at least 1.5
o
F below the cooling setpoint or 1.5
o
F above the
heating setpoint, whichever produces the highest econo-
mizer control setpoint.
Example:
Heating Setpoint = 68 o
Cooling Setpoint = 70
o
The control temperature for the economizer will be
1.5
o above the heating setpoint due to it producing
the least amount of offset.
Example: (continued)
Heating Setpoint = 55
o
Cooling Setpoint = 75
o
Because of the spread between the heating and cooling
setpoints, the control will choose to control the economizer
at an offset temperature of 1.5
o F below the cooling setpoint.
This will be the highest resulting control setpoint tempera-
ture while maintaining the least amount of offset.
The percentage that the economizer dampers open is
based on two factors:
1. The zone temperature minus the economizer setpoint,
and
2. The zone temperature minus the outdoor air temperature.