3
. Zone sensor operation
The zone sensors provide the user controls and zone
temperature sensing function. The operator controls are
as follows:
UNIT MODE
HEAT - Heat functions only enabled
AUTO - Auto-changeover between cooling mode and
heating mode as required by zone load. (on some models)
OFF -
No heating or cooling functions
COOL - Cooling functions only (including economizing)
enabled
FAN SETTINGS
FAN AUTO - Fan runs only when heating or cooling
functions are required
FAN ON -
Fan runs at all times. This is the setting
used when minimum ventilation is
required. When the fan is running, the
economizer dampers will be open to at
least minimum position.
• Optional Remote Panel Indicator Lights
(Optional)
SYS ON -
Indicates that power is applied to the unit
and the UCP is functioning correctly. This
indicator will flash at a 1 second rate to
indicate operation in one of the test modes.
HEAT -
Indicates that at least one stage of heat is
ON. This indicator will flash at a 1 second
rate to indicate a heat failure when limit
TCO1 and/or TCO2 has tripped.
COOL -
Indicates that cooling is active. This could
be economizing and/or compressor cooling.
This indicator will flash at a 1 second rate to
indicate a cool failure. Sources of cool
failure include high pressure controls if
present and zone sensor failures.
SERVICE - Indicates that a problem exists in the supply
air stream. Could be dirty filters, broken
drive belt or other functions depending on
what sensors or switches are installed on
the fan/filter status input.
MODULE NAMES
UCP - Unitary Control Processor (standard component)
This is the heart of the system. The computer and
program reside in this module. The minimum
configuration will include the UCP and one of the
zone sensor modules.
ZSM - Zone Sensor Module (accessory component)
Replaces thermostat, provides operator controls
and the zone temperature sensor for the UCP. A
complete line of ZSMs is available with various
combinations of features. A zone sensor module, or
a CTI is required for each system.
UEM - Unitary Economizer Module (standard component
on economizer accessory) This module provides
the hardware necessary to connect the economizer
accessory to the UCP
TCI - TCI Communications Interface. This interface
module is required to connect the system to an ICS
BUILDING MANAGEMENT SYSTEM. i.e. - Tracer
or Tracker.
CTI - Conventional Thermostat Interface (BAYCTHI001
accessory component) This module can be used in
special applications that require the installation of
select electro-mechanical thermostats to interface
with the UCP, instead of using a zone sensor
module (ZSM).
UNIT FEATURES
. Self-test/Auto-configuration
At power-up, the system will perform a series of tests to
verify correct operation and configure itself automatically,
based on the unit wiring harness. This means there is no
field configuration necessary when replacing the UCP,
with exception of the zone comfort switch settings.
. Cooling Minimum ON/OFF times
To enhance compressor reliability, a minimum of 3
minutes ON/OFF time has been implemented in the
software. Any time power is applied or re-applied (e.g.
after a power failure), the 3 minutes minimum OFF time
is enforced to prevent short cycling a compressor
. Lead-Lag
Is a selectable configuration within the UCP which
alternates the starting of the compressors between the
two refrigeration circuits. To enable the Lead/Lag
function, cut wire 52F (PR) which is connected to
terminal J1-7 at the UCP. Refer to the unit wiring
diargam.) Each time the request for cooling is satisfied,
the designated lead compressor switches. Upon Power-
up Initialization, the control will default to the number one
compressor. When a Conventional Thermostat Inteface
(CTI) is used, Lead/Lag is functional except during the
test mode.
