155
JOHNSON CONTROLS
5276178-JIM-C-0118
5
using the SETPOINTS key, EXHAUST subsection of
the User Interface.
“EXHAUST OUTPUT FOR FAN STOP”
must be set
using the SETPOINTS key, EXHASUT subsection of
the User Interface.
Operation
This option is available on all units. A variable voltage
analog output from the Unit Control controls the
position of the exhaust damper. The output is based
on the difference between the actual building pressure
and
“BUILDING PRESSURE SETPOINT”
. If the
actual building pressure is greater than the
“BUILDING
PRESSURE SETPOINT”
the Unit Control will initiate
a voltage ramp to the exhaust damper. The rate at
which the (voltage) increases will vary based on the
difference between the actual building pressure and
the
“BUILDING PRESSURE SETPOINT”
. The User
Interface will show this output as a %. 0V is 0% and
10V is 100%. This output can be found at terminals 3
and 4 of terminal block TB9 of the Unit Control.
When the percentage output to the exhaust damper is
more than or equal to the
“EXHAUST OUTPUT FOR
FAN START”
the Unit Control will send a binary signal
to the exhaust motor and the motor will start. This
binary output originates at terminal 4 of terminal block
TB1 of the Unit Controller.
The exhaust damper will then modulate to maintain the
“BUILDING PRESSURE SETPOINT”
.
When the percentage output to the exhaust damper is
less than or equal to the
“EXHAUST OUTPUT FOR FAN
STOP”
the Unit Control will remove the binary signal
to the exhaust motor and the motor will stop.
Modulating Exhaust with A VFD
Required Programmed Values
“POWER EXHAUST TYPE”
must be set to
“MODULATE DAMPER - VFD”
through the OPTION
key, EXHAUST subsection of the User Interface.
“BUILDING PRESSURE SETPOINT”
must be set
using the SETPOINTS key, EXHAUST subsection of
the User Interface.
“EXHAUST OUTPUT FOR FAN START”
must be set
using the SETPOINTS key, EXHAUST subsection of
the User Interface.
“EXHAUST OUTPUT FOR FAN STOP”
must be set
using the SETPOINTS key, EXHASUT subsection of
the User Interface.
Operation
This option is available on all units. A variable voltage
analog output from the Unit Control varies the speed
of the VFD exhaust motor. The output is based on the
difference between the actual building pressure and
“BUILDING PRESSURE SETPOINT”
. If the actual
building pressure is greater than the
“BUILDING
PRESSURE SETPOINT”
the Unit Control will initiate a
voltage ramp to the VFD. The rate at which the (voltage)
increases will vary based on the difference between
the actual building pressure and the
“BUILDING
PRESSURE SETPOINT”
. The User Interface will show
this output as a percentage (0V is 0% and 10V is 100%).
This output can be found at terminals 3 and 4 of terminal
block TB9 of the Unit Control.
When the percentage output to the VFD is more than or
equal to the
“EXHAUST OUTPUT FOR FAN START”
the Unit Control will send a binary signal to the exhaust
fan VFD and the motor will start. This binary output
originates at terminal 4 of terminal block TB1 of the
Unit Controller.
The speed of the VFD will then modulate to maintain
the
“BUILDING PRESSURE SETPOINT”.
When the percentage output to the VFD is less than or
equal to the
“EXHAUST OUTPUT FOR FAN STOP”
the Unit Control will remove the binary signal to the
exhaust fan VFD and the motor will stop.
RETURN FAN OPERATION
This feature is not available on this product.
VENTILATION SYSTEM
Overview
The Unit Controller can be configured for several
different damper and ventilation options. The damper
options are:
•
None
•
2-Position
•
Standard
Everything except the NONE and 2-POSTION
Summary of Contents for 40 25 TON
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