Sutron MONITOR, Operation & Maintenance Manual

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Diff C, Diff D, Diff E
Connection: Diff C (6-7)
Diff D (8-9)
Diff E (18-19)
Optional connection to VREF (5) and AGND (4) as needed
Excitation
(VREF)
Analog
Gnd
_
SDR with Analog
Input Option.
4 5 6 7
+
Measurements Diff C, Diff D and Diff E are designed to operate with a special
type of analog output found on many sensors that use a “bridge” configuration or
any sensor that outputs a very small voltage. This input type has a “+” and “-“
input that connects to the sensor output.
Typically a bridge sensor will be powered on “VREF” (sometimes referred to as
excitation), have a “” and “signal –“, and provide a wire for the analog
ground. NOTE: If after wiring the sensor, it displays a negative reading, you may
reverse the “+” and “-“ leads coming from the sensor.
NOTE: The common mode voltage for differential sensors is 0.5V to 3.7V. If the
sensor is floating, it should be tied to VREF and not to AGND in order to
maintain this common mode voltage. Sensors that are not powered by
MONITOR are generally floating (such as a pyranometer).
Input Range
This setting is relevant only to analog differential measurements. The following
options are available:
•
-39 to +39mV
•
-312 to +312mV
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