Sutron Corporation 8310 & 7310 Users Manual 8800-1125Rev. 2.7 (BETA) 4/16/2014 pg. 79
Channel number where sensor is connected. Note:
if you select differential below, you will connect to
a pair of channels (1:2, 3:4, 5:6, or 7:8). Specify the
channel number of the positive output. Typically
the positive output will be connected to the odd
channel of the pair (e.g. 1, 3, 5)
0-5V/+2.5V | 78mV (2.5 is the fullscale for a
differential input.)
Milliseconds, time to wait after VREF is turned on
before making the measurement. See description
below.
Hz (default 60) See description below
Using Differential
Differential measurements allow measuring inputs that are not referenced to ground or
are across a device. Differential measurements are bipolar in that the positive input can
be either above or below the negative input in voltage. Even though the differential
measurement is bipolar, each input is still limited to a -0.1V to 5V range with respect to
the 8310’s power supply ground. Differential measurements tend to be slightly more
accurate than single ended since the measurement reference point can be precisely
defined. In the example below, the channel would be specified as 2 since the sensor
positive output is connected to A2.
Figure 3 Differential Voltage Measurement
Using FullScale
When using the 0-5V/+2.5V scale, the resolution of the built in analog module is 76
micro-volts. When measuring a device whose output is less than 78mV, a 2 micro-volt
resolution can be achieved by using the 78mV scale.
Using Settling Time
The settling time parameter allows the 8310 to accommodate slow responding sensors
that require a period of time to establish their proper output before being measured.
This could be due to a required warm up time, or it may be due to the sensor having a
high impedance output and trying to charge the cable capacitance of a long cable. For
devices that are always powered on, the settling time can be reduced in order to speed
the measurement and increase the measurement throughput.
Note: when sensors are muxed, the AIO module isn’t aware of when sensors are actully
“muxed-in”. Hence, you may need to set the mux settling time to wait additional time
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