Custom Sensor - Pin Definitions

Label Function Overview Ports
I Input 0v-2v = off, > 4v-24v = on RJ45 1&5, TB 7
O Output 0, 5v, 12v or 24v RJ45 2&8, TB 8
P Power 0, 12v, 24v RJ45 4, TB 6
G Ground Common RJ45 7, TB 3
A+ Analog+ differential analog, positive RJ45 3, TB 5
A- Analog- differential analog, negative RJ45 6, TB 4
RTD RTD Resistance Temperature Detector TB 1&2


Power (P) 

Power output is used to power connected sensors, and can be 12 or 24v.  Note: Current draw of the connected devices must be kept under 40 mA total, per output voltage (5v, 12v, 24v). This includes current on both the power pins and the output pins (combined).


Analog (A+,A-)

Analog is differential, and can vary between -2.048v and +2.048v. Applying larger voltages, even temporarily (such as during a sensor hot plug) can permanently damage the Analog Input! (so it's recommended that analog sensors that receive power from the mPort are connected first, and then the port is configured)


To connect a single-ended device, the A- pin can be grounded. Then the input voltage can vary between 0 and +2.048v.


To measure voltages higher then +2.048v, and voltage divider circuit can be used.

To measure 0-20mA or 4-20 mA current loops, a burden resistor can be used (such as 100 Ohms).



The Resistance Temperature Detector is type PT100 , with an alpha coefficient of 0.00385 ohms/ohm/°C. The RTD interface is 2-wire. Temperature measurements can vary between -50°C and +250°C.


Input (I1, I2)

Digital inputs.  RJ45 ports have 2, while terminal block has 1.  < 2v = logic "off", > 4v = logic "on" (approximately).


Output (O1, O2)

Digital outputs.  RJ45 ports have 2, while terminal block has 1.  Digital outputs are used to provide constant signals to connected sensors (such as a door sensor looping it back to a digital input), or to control connected machines (such as a relay).  They can be 5, 12 or 24v.

Note: 24v is present on RJ45 ports output 2 when the port is not configured, in order to support sensor auto-detect when that signal is looped back to input2.


RJ45 Pinout

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