Dwyer CDTA - Manual (Page 3)

Home Screen
The home screen displays up to two parameters during normal operation. The
parameters displayed on the home screen can be changed by the “DSP” setting in
the setup menu.
Set Point
When in the home display, a single press of either the UP or DOWN button will
display the current temperature set point value. Additional presses of the UP or
DOWN buttons will increase or decrease the set point by 1 degree per button
depression. Holding the UP or DOWN button will continuously change the set point
value until the button is released. The set point display will timeout and return to the
home screen after 5 seconds of inactivity. At this point the new set point value is
stored in non-volatile memory. The range of the set point value can be configured
with “SOH” and “SOL” values in the setup menu. A display is not required to
change the set point value.
Override
When on the home screen or when changing the set point, the override button
(middle button) can be pressed. When the override button is pressed, a snow flake
symbol is displayed momentarily to indicate the button was pressed.
Accessing Parameter Setup Menu
In order to access the parameter menu, press and hold the UP and DOWN buttons
for 3 seconds. Once in the parameter menu, pressing the UP or DOWN buttons will
cycle through the parameters. To change any of the parameters, press both the up
and down arrow buttons simultaneously. The word SET will display in the lower
right hand corner of the display. The UP or DOWN buttons can be used to change
the value of the parameter. Press both the UP and DOWN buttons simultaneously
to store the values. In order to go back to the home screen, press and hold the
DOWN button for 3 seconds.
Home Screen Configuration (DSP)
This value controls what information is displayed on the home screen. See table
below for possible values.
Units Selection (UNI)
This value controls the units that data is displayed in.
Set Point Low Limit Temperature (SOL)
This value sets a lower limit on the current set point value. The set point low limit
value is numerical setting that supports continuous change (increment/decrement)
by press and holding of either UP or DOWN button. If the new set point low limit
temperature is higher than the current set point temperature, then the set point
temperature will be set to the new set point low limit temperature.
Set Point High Limit Temperature (SOH)
This value sets an upper limit on the current set point value. The set point high limit
value is numerical setting that supports continuous change (increment/decrement)
by press and holding of either UP or DOWN button. If the new set point high limit
temperature is lower than the current set point temperature, then the set point
temperature will be set to the new set point high limit temperature.
Typical Barometric Pressure (BAR)
This value sets the typical barometric pressure for the location where the device is
mounted. The factory setting is for standard pressure at sea level. Adjusting the
barometric pressure gives a more accurate measurement, especially at higher
elevations.
CO
2
Calibration Process (CAL)
This value initiates a calibration sequence of the carbon dioxide sensor to a known
gas value. Read the calibration instructions before using this feature.
Relative Humidity Offset (OFH)
This value allows the relative humidity to be adjusted by a fixed amount to match
another calibrated measurement. The display shows the current relative humidity
value plus any previous offset value.
Temperature Offset (OFT)
This value allows the temperature to be adjusted by a fixed amount to match
another calibrated measurement. The display shows the current temperature value
plus any previous offset value.
Figure 7: Display Layout
Setting Value
“CH”
“CT”
“HT”
“TS”
“S”
“T”
“H”
“C”
Primary Value
CO
2
Concentration
CO
2
Concentration
Relative
Humidity
Temperature
Set Point
Temperature
Relative
Humidity
CO
2
Concentration
Primary Text
“PPM”
“PPM”
“%”
“°C” or “°F”
“°C” or “°F”
“°C” or “°F”
“%”
“PPM”
Secondary Value
Relative Humidity
Temperature
Temperature
Set Point
Secondary Text
“%”
“°C” or “°F”
“°C” or “°F”
“°C” or “°F”
Setting Value
“US”
“SI” Description
US Customary Units (°F, in Hg)
International System Units (°C, hPa)
Default Value
35°C (95°F) Minimum Value
Set Point Low Limit Maximum Value
50°C (122°F) Increment
1°
Default Value
20°C (68°F) Minimum Value
0°C (32°F) Maximum Value
Set Point High Limit Increment
1°
Default Value
1013 hPa
(29.9 in Hg) Minimum Value
677 hPa
(20.0 in Hg) Maximum Value
1016 hPa
(30.0 in Hg) Increment
1 hPa
(0.1 in Hg)
Default Value
0% Minimum Value
-30% Maximum Value
30% Increment
0.1%
Default Value
0% Minimum Value
-30° Maximum Value
30° Increment
0.1°
Side View of Transmitter
Figure 8
Remote Display Port
Up Override
Down