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ANALOG INPUTS (AI)
Analog inputs require parameters that define the input's
characteristics. Attributes of an AI include the linear range,
alarm limits, alarm differential, change of state (COS) enable,
and filter weight. The input values may be overridden by a
external system command or by using the input buttons on
®
the Simplicity
board. This is useful to override current
conditions to test certain control functions or modes.
BAS - Economizer override; if this option is enabled, an
external BAS system will control the economizer 2-10 VDC
signal through this pair of terminals.
ST - Space Temperature sensor is a field installed sensor
(PN: 025-38928-000 - w/ Override Button). The sequence of
control for space temperature is different depending on
whether the system is a VAV or CAV. See chapter on
Sequence of Operation for a detailed description of the ST
control modes.
SSA - Space Temperature Adjust is field installed. It is a slide
adjustment located on a space sensor (PN: 025-38927-000)
with a slide bar potentiometer. It is used to offset the space
temperature setpoint. This slide-bar is a 10K ohm
potentiometer. The programmable range for the Setpoint
adjust is +/- 5 °F. For example, if the Space Temperature
setpoint is set to 74 °F, the SSA is programmed to +/- 3 °F and
the SSA is adjusted fully to the + position, the new controlling
space setpoint will be 78 °F.
OAT - The outside air temperature sensor (PN: 031-01916-
000A) is a factory-installed 10 K NTC sensor. Its linear
ranging is from -50 °F to 250 °F.
OAH - Outside Air Humidity (PN: 031-09127-000-A) is a
factory-installed sensor manufactured by MAMAO. The OAH
sensor, installed only with enthalpy economizer, provides a 0-
10 VDC signal to the controller over a range of 0 to 100%
relative humidity. This input is used for the economizer
calculation to determine whether free cooling is available and
to switch between minimum outside air and using outside air
as the first stage of cooling.
SAT - Supply Air Temperature sensor (PN: 031-01915-000A)
is a factory-installed -50 °F to 250 °F, 10 K NTC sensor.
RAT - Return Air Temperature sensor (PN: 031-01917-000A)
is a factory-installed -50 °F to 250 °F, 10 K NTC sensor.
RAH - Return Air Humidity (PN: 031-09127-000-A) is a
factory-installed sensor manufactured by MAMAO, installed
only with dual enthalpy economizer. The control will calculate
the return air enthalpy using the relative humidity and return
temperature inputs.
LOW VOLTAGE DETECTION - This input monitors the 24
VAC for low voltage conditions. The input has two thresholds,
one at 16 VAC and one at 19.2 VAC. If the control needs to
turn on a contactor, it will look to see if the voltage is
above19.2 VAC before it will turn it on. If the voltage is not
above 19.2 VAC, it will hold off the contactor and flash the
appropriate flash code. This flash code is not an alarm. If the
control already has contactors pulled in, it will monitor the
Johnson Controls Unitary Products
voltage and drop the contactors and shut down if the voltage
drops below 16 VAC and flash the appropriate flash code.
REMOTE - the control will use 0-10 VDC from third-party
BAS to control SAT setpoints. Thermostat inputs override if in
conflict with Remote Control voltage input.
SPC TEMP - offset value from the space sensor offset
potentiometer.
CV/VAV - resistive value across terminals, to determine
which supply fan rules the control will follow.
Demand Ventilation / IAQ - Indoor Air Quality. The IAQ
expects a 0-10 VDC signal to the control from a field supplied
and installed Carbon Dioxide (CO
is monitored for adequate ventilation. In Demand Ventilation
Mode, as the CO
levels in the building rise above the
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programmed setpoint, more fresh air must be brought in. The
economizer is therefore adjusted to a more open position as
necessary. The linear ranging for IAQ sensor input is from 0
to 10,000 ppm. The Demand Ventilation setpoint is adjustable
from 0 to 2000 ppm and is set at the factory at 1000 ppm.
DPS - Duct Pressure Sensor is monitored by a factory-
installed 0-5 VDC transducer (PN: 031-01209-000A). The
high-pressure port sensing tube is installed in the field. The
sense tube should be located approximately two thirds of the
way down the duct plenum. To prevent an unstable signal
due to air turbulence, there should be no obstructions, turns
or VAV terminal boxes up or down-stream of the sense tube
location for at least 6 to 10 times the diameter of the duct.
The sensor is located in the control box just below the
®
®
Millennium
control.
Simplicity
BPS - The Building Pressure Sensor (PN: 031-01262-000A) is
a factory-installed Johnson Controls DPT-2640-522 transducer
that provides a 0 to 5 VDC signal to the controller over a range
from -0.25"WC to +0.25"WC. The transducer is located in the
control box just below the Millennium
sense tubes are field installed with the outside pressure being
sensed external to the unit. To avoid an erratic pressure
reading, the building pressure sense tube should be mounted
in an area away from the return air grill, discharge diffusers,
doors and windows.
BINARY INPUTS (BI)
APS - Supply Fan status is monitored by an Air Proving
Status switch (PN: 024-27557-000A) installed at the factory.
The APS monitors the difference in pressure between the
suction and discharge of the fan.
FOVR - Monitoring loop through the supply fan overload
module or VFD over torque indication.
HPS1-4, LPS1-4 - The refrigerant high pressure (HP) and low
pressure (LP) safety switches, are independently monitored
®
by the Millennium
Simplicity
control voltage from the control binary output is interrupted
and the status is monitored by the control.
G, OCC, P - These signals represent Fan (G), Building
Occupancy (OCC), and Building Purge (P) calls from the
351579-YTS-B-0608
) sensor. Indoor air quality
2
®
®
control. The
Simplicity
®
. If any switch opens, the
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