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IQ.I.C
= 2
(IAQ Discrete Override) — If the user sets
IQ.I.C
to 2 (IAQ Discrete Override), and
Configuration
SW.LG
IAQ.L
is set to OPEN, then an open switch reads low and a
closed switch reads high.
If the switch reads low, no action will be taken. If the switch
reads high, the economizer will immediately be commanded to
the IAQ Economizer Override Position. This can be set from 0
to 100% and can be found at
Configuration
IAQ
AQ.SP
IQ.O.P
.
FAN CONTROL FOR THE IAQ DISCRETE INPUT —
Under
Configuration
IAQ
AQ.CF
,
the
IQ.I.F
(IAQ Dis-
crete Input Fan Configuration) must also be set. There are
three configurations for
IQ.I.F
. Select the configuration which
will be used for fan operation.
This configuration allows the
user to decide (if the supply fan is not already running),
whether the IAQ discrete switch will start the fan, and in which
state of occupancy the fan will start.
IAQ ANALOG INPUT CONFIGURATION — This input is
an analog input located on the main base board (MBB). There
are 4 different functions for this input. The location of this con-
figuration is at
Configuration
IAQ
AQ.CF
IQ.A.C
.
The functions possible for
IQ.A.C
are:
• 0 = no IAQ analog input
• 1 = IAQ analog input
• 2 = IAQ analog input used to override to a set position
• 3 = 4 to 20 mA 0 to 100% economizer minimum position
control
• 4 = 0 to 10 kilo-ohms 0 to 100% economizer minimum
position control
Options 2, 3, and 4 are dedicated for third party control.
IQ.A.C
= 2
(IAQ Analog Input Used to Override) — Under
Configuration
IAQ
AQ.SP
,
set
IQ.O.P
(IAQ Economizer
Override Position). The
IQ.O.P
configuration is adjustable
from 0 to 100%. These configurations are also used in conjunc-
tion with
Configuration
IAQ
AQ.CF
IQ.A.F
(IAQ 4 to
20 mA Fan Configuration). There are three configurations for
IQ.A.F
and they follow the same logic as for the discrete input.
This configuration allows the user to decide (if the supply fan is
not already running), if the IAQ Analog Minimum Position
Override input will start the fan, and in which state of occupan-
cy the fan will start.
If
IQ.A.F
is configured to request the supply fan, then
configurations
D.F.ON
and
D.F.OF
need to be set. These
configuration settings are located under
Configuration
IAQ
AQ.SP
and configure the fan override operation based
on the differential air quality (DAQ). If DAQ rises above
D.F.ON
,
the control will request the fan on until DAQ falls be-
low
D.F.OF
.
NOTE: If
D.F.ON
is configured below
DAQ.H
, the unit is in
occupied mode, and the fan was off, then DAQ rose above
D.F.ON
and the fan came on, the economizer will go to the
economizer minimum position (
EC.MN
).
The 4 to 20 mA signal from the sensor wired to TB5-6 and
7 is scaled to an equivalent indoor CO
2
(IAQ) by the parame-
ters
IQ.R.L
and
IQ.R.H
located under the
Configuration
IAQ
AQ.S.R
menu. The parameters are defined such that
4 mA =
IQ.R.L
and 20 mA =
IQ.R.H
. When the differential air
quality DAQ (IAQ –
OAQ.U
) exceeds the
DAQ.H
set point
(
Configuration
IAQ
AQ.SP
menu) and the supply fan is
on, the economizer minimum vent position (
Configuration
IAQ
DCV.C
EC.MN
) is overridden and the damper is
moved to the
IQ.P.O
configuration. When the DAQ falls below
the
DAQ.L
set point (
Configuration
IAQ
AQ.SP
menu),
the economizer damper is moved back to the minimum vent
position (
EC.MN
).
NOTE: Configuration
OAQ.U
is used in the calculation of the
trip point for override and can be found under
Configura-
tion
IAQ
AQ.SP
.
IQ.A.C
= 3
(4 to 20 mA Damper Control) — This configura-
tion will provide full 4 to 20 mA remotely controlled analog in-
put for economizer minimum damper position. The 4 to 20 mA
signal is connected to terminals TB5-6 and 7. The input is
processed as 4 mA = 0% and 20 mA = 100%, thereby giving
complete range control of the effective minimum position.
The economizer sequences can be disabled by setting
Con-
figuration
ECON
E.SEL
to 0.
Complete control of the
economizer damper position is then possible by using a 4 to
20 mA economizer minimum position control or a 0 to
10 kilo-ohm 0 to 100% economizer minimum position control
via configuration decisions at
Configuration
IAQ
AQ.CF
IQ.A.C
.
IQ.A.C
= 4
(10 Kilo-ohm Potentiometer Damper Control)
— This configuration will provide input for a 10 kilo-ohm lin-
ear potentiometer that acts as a remotely controlled analog in-
put for economizer minimum damper position. The input is
processed as 0 ohms = 0% and 10,000 ohms = 100%, thereby
giving complete range control of the effective minimum
position.
CONTROLS OPERATION
Modes —
The
Comfort
Link™ controls operate under a
hierarchy of command structure as defined by three essential
elements: the System mode, the HVAC mode and the Control
mode. The System mode is the top level mode that defines three
essential states for the control system: OFF, RUN and TEST.
The HVAC mode is the functional level underneath the
System mode which further defines the operation of the
control. The mode selection process is shown in Appendix D.
The Control mode is essentially the control type of the unit
(
Configuration
UNIT
C.TYP
). This defines from where
the control looks to establish a cooling or heating mode and
whether 2 stages or multiple stages of cooling capacity opera-
tion are controlled.
Furthermore, there are a number of modes which operate
concurrently when the unit is running. The operating modes of
the control are located at the local displays under
Operating
Modes
.
See Table 42.
Currently Occupied (
OCC
) — This variable displays the
cur-
rent occupied state of the unit.
Timed Override in Effect (
T.OVR
) — This variable displays
if the state of occupancy is currently occupied due to an
override.
DCV Resetting Minimum Position (
DCV
) — This variable
displays if the economizer position has been lowered from its
maximum vent position.
IQ.I.F
= 0
Minimum Position Override Switch input
will not start fan
IQ.I.F
= 1
Minimum Position Override Switch input
will start fan in occupied mode only
IQ.I.F
= 2
Minimum Position Override Switch input
will start fan in both occupied and unoccu-
pied modes
IQ.A.F
= 0
IAQ analog sensor input cannot start the
supply fan
IQ.A.F
= 1
IAQ analog sensor input can start the supply
fan in occupied mode only
IQ.A.F
= 2
IAQ analog sensor input can start the supply
fan in both occupied and unoccupied modes
Summary of Contents for WEATHERMAKER 48/50AJ
Page 103: ...103 Fig 15 Typical Main Control Box Wiring Schematic 48 50AJ AK AW AY Units cont a48 8355 ...
Page 104: ...104 Fig 16 Typical Main Control Box Wiring Schematic 48 50A2 A3 A4 A5 Units a48 8355 ...
Page 105: ...105 TO NEXT PAGE Fig 17 Typical Auxiliary Control Box Wiring Schematic A48 7294 ...
Page 106: ...106 Fig 17 Typical Auxiliary Control Box Wiring Schematic cont a48 8356 ...
Page 107: ...107 Fig 18 Typical 2 Stage Gas Heat Wiring Schematic Size 051 and 060 Units Shown a48 8357 ...
Page 113: ...113 Fig 22 Typical Power Schematic 48 50A2 A3 A4 A5060 Unit Shown ...
Page 114: ...114 SW1 SW2 OR DEHUMIDIFY SWITCH Fig 23 Typical Controls Option Wiring Schematic a48 8361 ...
Page 115: ...115 Fig 24 Typical Small Chassis Component Location Size 020 035 Units a48 8362 ...
Page 116: ...116 Fig 25 Typical Large Chassis Component Locations Size 036 060 Units A48 7302 ...
Page 169: ...169 APPENDIX C VFD INFORMATION cont Fig F Internal Enclosure Fan Replacement A48 7716 ...