Sutron Xpert2, Руководство по эксплуатации и обслуживанию

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Current (4-20mA): This is for making current measurements in the range of 0 to 20ma. It
requires one input channel for a single-ended measurement or an input channel pair for a
differential measurement. The dialog changes slightly when this measurement type is selected:
When measuring using an Xpert AIO module, make sure “8080-0003” is checked (this option is
typically only used on the Xlite/9210).
DC resistance: To measure resistance, set-up an excitation channel and hook the device or
medium to be measured between this channel and ground. The I/O module will do a voltage over
current calculation to determine the resistance. The excitation voltage should be set to a value
appropriate to the approximate resistance being measured. DC resistance uses a built-in precision
20 ohm resistor as the reference for the resistance measurement.
AC resistance: If this is selected, the I/O module will take two measurements for every
measurement value the block outputs. The first measurement is done using the voltage specified
by the excitation voltage and the second with this voltage negated. This can be used in cases
where applying a DC excitation voltage would causes undesirable changes to the medium being
measured.
Thermistor: This is a specialized resistance measurement geared for thermistors. A 10k internal
resister is used instead of the standard and the excitation channel voltage is overridden to be 5V.
The output is the thermistor’s resistance. If the desired output is temperature, then please review
the Air Temperature block to see if it directly supports the thermistor to be measured.
Volts HiGain: When you select the “Volts HiGain” measurement type, a voltage measurement is
made using hi gain. The maximum input voltage is 312mV when measuring using the 8080-0003
Analog IO module, and is 78mV when measuring using the 8080-0007 Analog IO module.
Volts x128: When you select the “Volts x128” measurement type, a voltage measurement is
made using very high gain. The maximum input voltage is 39mV when measuring using the
8080-0003 Analog IO module, and is 19mV when measuring using the 8080-0007 Analog IO
module.
Differential measurements can be made for each of the above Measurement choices. If you
specify a differential measurement, be sure to select only channels 1, 3 or 5