Measurement Computing CIO-EXP16, Руководство пользователя

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CIO-EXP16 User's Guide Installing the CIO-EXP16
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Input ground reference (G pad) — provides a reference to ground through a 100 k resistor. This
reference prohibits floating thermocouple readings.
You should bridge the C and G pads with solder for each channel that you install a thermocouple. Bridging
these pads reduces the noise present when you take temperature readings, and helps to obtain a more accurate
temperature reading. The C, V, and G pads are all open when the board is shipped.
How to add and remove a solder bridge
To add a solder bridge to a solder gap switch, place a drop of solder on one of the pads and pull the soldering
iron perpendicular to the pads from their center. To remove a solder bridge, slide the soldering iron toward one
pad or the other. Take care not to overheat the solder, or the pads may lift.
Configuring the A/D board
Use Insta Cal to change the following configuration options on your DAS08 or DAS16 Series board.
Single-ended mode
DAS08
setup: The input mode of the A/D board must be single-ended to be compatible with the CIO-EXP16
outputs. Some of the boards in the DAS08 series have differential inputs that can be converted to single-ended
inputs. Refer to the user's manual for your hardware for information on conversion to single-ended inputs.
DAS16
setup: The input mode of the A/D board must be single-ended to be compatible with the CIO-EXP16
outputs. Most of the DAS16 series is switch-selectable for either 8 differential or 16 single ended inputs. When
used with the CIO-EXP16, set the switch to 16 channel, single-ended mode.
Range
If the range of your A/D board is switch-selectable, and you are using thermocouples, set the range of the DAS
board to ±5 V, if available, or ±10 V if not. Some software packages base the calculation of temperature on
these ranges only.
If you are not using thermocouples, set the range of the DAS board to accommodate the maximum output
expected from the CIO-EXP16 board.
Polarity
If your A/D board has a UNI / BIP switch for setting the range to either unipolar or bipolar, the preferred setting
is BIP (bipolar).
If the range on your A/D board is fully programmable, the software you use for temperature measurement will
determine the correct range to use.
Calibrating the CIO-EXP16
You should calibrate the CIO-EXP16 after you first connect to a A/D board, if you change the gain setting of
the input amplifier, and at 6 month intervals.
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