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351579-YTS-B-0608
Power Exhaust - (ON) - This tells the control if it has the Power
Exhaust option installed.
Economizer Damper Position for Exhaust Fan to turn ON
(Non-Modulating PE Only) - (60%) - This tells the control the
Economizer Damper position to turn on the Exhaust Fan. This
value is based on the 0%-100% output drive signal from the
controller to the economizer damper actuator.
Economizer Damper Position for Exhaust Fan to turn OFF
(Non-Modulating PE only) - (20%) - This tells the control the
Economizer Damper position to turn off the Exhaust Fan. This
value is based on the 0%-100% output drive signal from the
controller to the economizer damper actuator.
Modulating Exhaust - (OFF) - This tells the control if the
Power Exhaust is Modulating or not. A modulating exhaust will
be equipped with a Building Pressure Sensor [BPS]. A Non-
Modulating exhaust will look to the economizer damper position
to energize the EXD output. If the sensor gets disconnected, or
fails, an alarm is set. The alarm can be turned off by correcting
the sensor problem (or; by turning off this option). The control is
not in this case self-configuring. It will not automatically use the
Building Pressure Sensor if the sensor is connected.
Exhaust VFD Installed - (OFF) - If the unit has a VFD, the EXD
output will be enabled when the supply fan is ON.
Exhaust Damper Position For The Exhaust Fan To Turn On
(Modulating Only) - (80%) - This tells the control the Exhaust
Damper position at which to turn on the Exhaust Fan. This
value is based on the 0%-100% output drive signal from the
controller to the damper actuator.
Exhaust Damper Position For Exhaust Fan To Turn Off
(Modulating Only) - (20%) - This tells the control the Exhaust
Damper position to turn off the Exhaust Fan. This value is
based on the 0%-100% output drive signal from the controller to
the damper actuator.
Building Pressure Setpoint - (+0.100"WG) - This is the
pressure setpoint the control will maintain when operating a
Power Exhaust. The Building Pressure Setpoint is adjustable
from -0.200"WG to +0.200"WG. The factory programmed default
is +0.100"WC. This setpoint is used when the exhaust control is
implemented as Proportional Control (with a Modulating Exhaust
Air Damper or VFD controlled from building static pressure), or
as a Two-position Control using building static (Power Exhaust
Fan controlled on-off from building static pressure).
Economizer - (ON) - This tells the control that there is an
Economizer Installed.
Economizer Min Position - (20%) - This tells the control what
the minimum outdoor damper position will be for the Occupied
mode. Adjustable from 0-100%, the Economizer Minimum
Position default is 20%.
Economizer First Stage Setpoint - (55 °F) - This tells the
control what Supply Air Temperature to maintain for a call for
first stage of cooling. This is used only during Constant Volume
cooling mode with Economizer operation. The setpoint is set at
55 °F with an adjustable range from 40 °F to 65 °F.
12
Economizer Second Stage Setpoint - (50 °F) - This tells the
control what Supply Air Temperature to maintain for a call for
second stage of cooling. This is used only during Constant
Volume cooling mode with Economizer operation. This setpoint
is set at 50 °F with a range from 40 °F to 65 °F.
Outside Air Humidity (OAH) Sensor Enable - (OFF) - This
setting tells the control that it is expected to use Outside Air
Enthalpy (calculated from Outside Air Temperature and Outside
Air Relative Humidity sensed values) to decide if Outside Air
can be used for cooling.
The control is self-configuring to the best available decision
strategy for free cooling availability. For example, if it detects
that OAT and OAH and RAT and RAH sensors are all
connected and reliable, will self-configure for Differential
Enthalpy operation. If one of the return air sensors should fail,
the control will reconfigure for Outside Enthalpy operation, etc.
If the OAH Sensor Enable option is turned ON, it means that the
Outside Enthalpy Operation, or better decision strategy, is
expected (and supported by installed sensors). If the
appropriate sensors are not installed, or one of them failed, a
sensor failure alarm is set. The alarm can be turned off by
turning off the OAH Sensor Enable option. Thus, the option
setting is used to reflect the desired operation and mainly to
control sensor failure alarms
The option setting can be viewed as specifying that (the self-
configured economizer decision strategy has to be at least this,
or better, otherwise an alarm is set). If the option is OFF, the
control still may self configure to Outside Enthalpy Operation, or
even to Differential Enthalpy Operation (if all needed sensors
are available), but this option setting will allow also the decision
strategy based on only OAT (in case other sensors fail, or are
not installed) without setting an alarm.
Outside Air Enthalpy Setpoint - (27 BTU/LB) - This tells the
control an outside air enthalpy limit. Below this limit, outside air
is available for cooling. See enthalpy chart. This parameter
uses a one BTU/LB hysteresis on each side of the limit. The
limit is preset to 27 BTU/ LB with an adjustable range from 10 to
50 BTU/LB.
Return Air Humidity (RAH) Sensor enable - (OFF) - This tells
the control that it will compare Outside Air Enthalpy (calculated
from Outside Air Temperature and Outside Air Relative
Humidity sensed values) and Return Air Enthalpy (calculated
from Return Air Temperature and Return Air Relative Humidity
sensed values). The control will use the air stream with the
lower enthalpy for cooling.
The control is self-configuring to the best available decision
strategy for free cooling availability. For example, if it detects that
OAT and OAH and RAT and RAH sensors are all connected and
reliable, will self-configure for Differential Enthalpy operation. If
one of the return air sensors should fail, the control will stop using
rules that involve RAH and set an alarm.
If the RAH Sensor Enable option is turned ON (and supported
by installed sensors), Differential Enthalpy Operation can be
enabled. If the appropriate sensors are not installed, or one of
them failed, a sensor failure alarm is set. The RAH alarm can
.
Johnson Controls Unitary Products
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