MC Technologies MC100 - Current Inputs 0 - 20 Ma

MC100
Mobile programmable gateway
MC Technologies GmbH, Kabelkamp 2, 30179 Hannover, Germany
Tel: +49511 67 69 99-0, Fax: +49511 67 69 99-150, Website & Shop: www.mc-technologies.net, Email: info@mc-technologies.net
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The input current at 10V is approx. 2 mA
Note: The applied DC voltage must not exceed 10V.
Function: Reading the voltage inputs
Port
Parameter
Read
Write
Path
+A1,-A1
Value
x
/sys/senst2_board/voltage_in/1
+A2,-A2
Value
x
/sys/senst2_board/voltage_in/2
Example: Read voltage at ADC input +A1,-A1
Command: cat /sys/senst2_board/voltage_in1/value
Response: e.g. 6400
Note: Conversion to volts
Formula: Voltage in Volt = value / 1000
Example: Value = 6400 corresponds to 6.4V
Current inputs 0 - 20mA
The analog current inputs of the MC100 SensT2 have two operating modes.
1. Supply of a current - current from the sensor - sensor with own power supply
2. Low side shunt - with power supply for the sensor
11.6.4.1 Supply of a current - current from the sensor
The connected sensor has its own power supply and a current output with a maximal
current of 20mA.
The sensor is connected to -A3 or -A4 against ground.
Port
Description
-A3
Positive connection input 3, current output of the sensor
GND
Negative connection Input 3, sensor ground
-A4
Positive connection input 4, current output of the sensor
GND
Negative connection Input 4, sensor ground
11.6.4.2 Low Side Shunt - power supply for the sensor
It is possible both to supply the sensor with power and to measure the current it draws over
the same two wires. The sensor will be powered from the MC100 SensT2. A voltage is
applied to the terminals +A3 or +A4 for this purpose. Connect the sensor to +A3 and A3 or
+A4 and -A4.