CONNECTING SENSORS TO THE ADC-T
Standard temperature sensors are included with the ADC-T Temperature Interface (4 with the ADC-T4, 8 with the
ADC-T8 and 12 sensors with the ADC-T12). The standard sensor is provided in a TO-92 package. A variety of
temperature sensor options are available. These include wall mount sensors, outdoor sensors and shields, extended
range sensors, extended lead sensors, refrigerant and water line sensors, air duct sensors, TO-46 package and
other types. Please contact EECI technical support for more information.
When a temperature input is left unconnected, the ADC-T temperature Interface will display a blank indication for that
temperature input. When a temperature input is shorted, a very low negative temperature will be displayed.
A large variety of sensors, transducers, load cells and other devices that provide an analog output may be connected
to the ADC-T. Most types of sensors may be located up to 1,000 feet from the ADC-T. Eight pull up resistors are pre-
installed on the underside of the ADC-T for 2 wire temperature sensors that receive power from the USB port. The
pull up resistor will normally have to be removed for transducers or sensors that receive power externally. The cable
used to connect sensors to the ADC-T should be twisted pair or shielded twisted pair to suppress environmental
noise. Low cost CAT 5 cable works well when multiple sensors are in the same location.
TEMPERATURE SENSOR CALIBRATION
After all your temperature sensors are connected and you have valid readings, the temperature inputs may be
calibrated by placing a thermometer next to the temperature sensor and allowing the thermometer to stabilize to room
temperature for about 5 to 10 minutes. Double click on that temperature sensor reading to bring up the calibration
box and enter the temperature reading of the thermometer. Repeat for additional temperature sensors. Calibration
effects only the offset setting for that temperature input and can be viewed by clicking the Analog Setup button.
The standard sensors that are provided with the ADC-T8 are precision temperature sensing ICs that provide a linear
voltage increase of 10mv per degree C (or 5.555mv per degree F) with a theoretical output of 0 volts at 0 degree K.
This is how the offset of -459 degrees is obtained since degrees K is 459 less then degrees F (or 273 degrees less
then degrees C). The scale is determined by dividing the 4.096 volt reference by 1024 increments (10 bit, 4mv per
increment). Dividing 4mv by the 5.555mv per degree F output of the sensor gives you a scale of .72.
MOUNTING
The ADC-T Analog to Digital card may be mounted in an enclosure or on a metal mounting panel
using the MT-1 stand-off mounting hardware as shown below. The ADC-T will attach to the 4 stand-off spacers
using 4-40 machine screws (4 mounting holes are provided on the ADC-T). Contact technical support for more
information on mounting panels and various mounting layouts.
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ADC-T
+
-
+
-
Twisted Pair
Pressure
Transducer
Power
-
+
ADC-T
+
-
+
-
Twisted Pair
2 wire
temperature
sensor
ADC-T
SIDE
VIEW
1/2" Stand-Off
1/4" 4-40 Machine Bolt
1/4" 4-40 Machine Bolt
MP-C
Mounting Panel
with MT-1
Stand-Off Kit
SETUP FUNCTIONS
RAW ANALOG DATA
The ADC-T will
present the raw analog
data as a number between:
0 to 255 (8 bit)
0 to 1023 (10 bit)
o to 4095 (12 bit)
when in single ended
mode and a number
between:
-128 to +127 (8 bit)
-512 to +511 (10 bit)
-2048 to +2047 (12 bit)
when in differential mode.
Relay and Input labels
may be changed by
clicking the Relay Control
or Input Setup buttons.
Click the Analog Setup
button to make changes to
the analog labels, suffix,
scale, offset or precision.
These also apply to
logged data.
NOTE:
Once a change is made, the Apply Button will appear. Changes will not be applied until you click the Apply
button. The changes are saved to the adct.ini file.
To completely automate the ADC-T, check Start Minimized, Driver Only and Allow External
Commands. In this mode of operation, your program has complete control of the ADC-T and the User
Interface does not open. *do not check unless the ADC-T is always connected to a USB port.
**the default sample rate is 250ms (4 times per second). This is the rate at which all analog inputs are updated.
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Driver Auto Loads
on System Start*
Rate at which
Analog Inputs
are Updated**
Start the data logger by
checking the Enable
box. The logger will roll-
over or stop based on
the setting in the Max
Entries box. The Data
Interval may be set to
minutes or seconds and
will log the data based
on the setting in the box.
Load Driver Only
and show Tray
Icon when Driver
Loads
Click to Refresh
Com Ports
(use the
pull-down to select, then
Apply to set)
