Carrier 50EW, 50EJ, 50EY, 50EK installation instructions Ð Field Control Remote Start/Stop

Features with sensor control of unit with computer access are:

·365 day timeclock with backup (supports minute, hour, day of week, date, month, and year)

·daylight savings time function

·occupancy control with 8 periods for unit operation

·holiday table containing up to 18 holiday schedules

·ability to initiate timed override from T-55 or T-56 sensors

·ability to use multiple space temperature sensors to aver- age the space temperature

·supply air temperature reset for the supply air temperature set point

·temperature compensated start to calculate early start times before occupancy

·access to the Display, Maintenance, Con®guration, Serv- ice, and Set Point data table through network software

When the unit is equipped with a ®eld-supplied space tem- perature sensor and a remote contact closure (remote start/ stop) on the base control board, the occupied default set points will monitor unit operation. The occupied default set points are 78 F cooling and 68 F heating (if electric heat is in- stalled). See Fig. 11 for remote start/stop wiring.

NOTE: For units which have not had the base unit control board accessed via software to set an occupancy schedule, the remote start/stop closure will allow the unit to operate in the pre-con®gured occupied default set points (based on return- air temperature) of 78 F cooling and 68 F heating. Without this feature, the unit will control to the unoccupied default set points of 90 F cooling and 55 F heating (if electric heat is installed).

An electronic expansion board may be ®eld-installed to provide the following features:

·control of modulating economizer damper to maintain indoor air quality (IAQ) when outdoor conditions are suitable

·provide discrete inputs for fan status, ®lter status, ®eld- applied status, and demand limit

·provide an output for the external alarm light indicator

When the unit is connected to the CCN (Carrier Comfort Network), the following expansion board features can be utilized.

·perform Demand Limit functions based on CCN loadshed commands or the state of the discrete input

·alarm monitoring of all key parameters

·CCN protocol

·provides power exhaust ®re outputs for direct control of modulated power exhaust stages during ®re or smoke modes

·smoke control modes including evacuation, smoke purge, pressurization, and ®re shutdown (modulating power ex- haust required)

·provides CCN IAQ participation

See Carrier TEMP or VVT (Variable Volume and Tem- perature) literature for complete TEMP (single zone) or VVT (multi-zone) application information.

Features with Sensor Control of Unit (Network Applica- tions) Ð The base control board provides, as standard, a con- nection for use with a Carrier VVT system and can also be integrated into a Carrier Comfort Network.

When the unit is accessed via a PC equipped with Com- fort Works, Building Supervisor, or Service Tool, the fol- lowing features can be accessed:

·on-board timeclock can be programmed

·occupancy schedules can be programmed

·unit set points can be changed

·alarms can be monitored

This access is available on the base control board via a RJ-11 phone jack or a 3-wire connection to the communi- cation bus. See Fig. 12. The timeclock has a 10-hour minimum back-up time to provide for unit power off for servicing unit

or during unexpected power outages. For complete Carrier Comfort System (CCS) or Carrier Comfort Network (CCN) features and bene®ts, refer to the product literature.

VARIABLE AIR VOLUME (VAV) APPLICATIONS

Features with Stand-Alone Applications Ð A VAV unit is capable of providing unoccupied cooling controlling to a 90 F return-air temperature utilizing the factory-supplied return- air thermistor located below the return-air damper in the return- air section for unit control. The unit will provide unoccupied heating (if electric heat is installed) controlling to a 55 F return-air temperature. Also provided is a morning warm-up which is initiated by the Occupied mode (if electric heat is installed) and continues until the return-air temperature rises to 68 F. The unit will provide occupied cooling with a de- fault temperature of 55 F for the supply air. The supply-air temperature is measured by the supply-air thermistor, lo- cated in the indoor fan compartment.

Standard features of a VAV unit with a remote start/stop switch are:

·control of an outdoor condenser fan based upon outdoor air temperature

·control of modulating economizer to provide free cooling when outdoor conditions are suitable, using supply air tem- perature as a set point

·support of remote occupied/unoccupied input to start or stop the unit

·provide power exhaust output to an external power ex- haust controller

·support supply air temperature reset to offset supply air set point

·support a ®eld test for ®eld check out

·support linkage to DAV systems

·cooling capacity control of 6 stages plus economizer with compressors and unloaders to maintain supply air tem- perature set point during occupied periods

·control of one stage of heat to maintain supply air tem- perature at supply air set point during occupied periods

·provide a variable frequency drive high voltage relay out- put to enable VFD

·control of heat interlock relay

With the addition of a remote start/stop switch heating or cooling is enabled during unoccupied periods as required to maintain space temperature to within unoccupied set points.

NOTE: On units running Version 1.0 of the Unit Control Software, the remote start/stop switch is connected to R and Y1. On units running Version 2.0 of the Unit Control Software, the remote start/stop switch is connected to R and W1.

Fig. 11 Ð Field Control Remote Start/Stop

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