Installation and Setup of Pressure Transducer with Voltage Output

This guide explains how to configure your Zenseio station and wire a voltage pressure transducer / transmitter using GPI2 or GPI3 + VAUX.

These instructions are applicable only to pressure transducers with voltage output. Pressure transducers with 4-20mA output are supported, but require a different procedure. Please refer to the appropriate Zenseio user guide.

Pressure transducers that have voltage output (0-5V or 0-10V) can be connected only to GPI2 or GPI3 ports.

Pressure transducers with output voltage range less than 5V or with high output impedance are not recommended due to potential analog accuracy loss.

1. Setup

1. In Zenseio mobile configuration app:
   
1. Set VAUX voltage output to 12V (or the excitation voltage required by your sensor).
2. Select “Voltage” mode on the chosen GPI port (GPI2 or GPI3).
   
3. Set settling time 1000 ms (or the required measurement duration for your sensor).
4. For "Supply VAUX?", select "Yes".
   
5. 
   
   
2. Wire connections (Wire color coding may differ between sensor models. Always refer to the specific sensor’s instruction manual): 
1. Connect black wire to GND.
   
2. Connect red wire to VAUX.
   
3. Connect green wire to the selected GPI port (GPI2 or GPI3).
   
4. 

Verify Operation

1. Press the user button inside the device.
   
2. Wait approximately 1 minute.
   
3. Open ZenConfig → read NFC → Status page.
4. Check "Last GPI2 Reading". Expected value: between 4 mA (zero pressure) and 20 mA (full-scale pressure)
   

Troubleshooting if readings are incorrect:

1. Reading close to 0V or unstable
   
1. Incorrect GPI port mode
   
2. VAUX not enabled
   
3. Sensor misconnected
   
4. Sensor output fluctuating near 0 V, but still within sensor’s accuracy tolerance (e.g., ±1% FS) - this is correct
   
2. Reading exceeds sensor range
   
1. Sensor misconnected
   
2. Jumper wire installed between VAUX and GPI2C (do not install this jumper for voltage sensor, but only for 4-20mA sensor)
   
3. Wrong / unexpected voltage, given known pressure
   
1. VAUX voltage too low
   
2. Settling time too short
   
3. Wrong GPI mode set
   
4. Sensor incompatible (sensor's internal resistance too high > 1 KOkm)
5. Voltage fluctuating within sensor’s accuracy tolerance (e.g., ±1% FS) - this is correct

2. Data interpretation/scaling

(in your application software)

The formula:

Pressure = (Full-Scale Pressure Range * Measured Output Voltage) / Full-Scale Output Voltage

where:

1. Full-Scale Pressure Range = sensor’s maximum rated pressure (e.g., 100 psi, 200 psi, 10 bar)
   
2. Measured Output Voltage = current sensor output in Volts (e.g., 3.2 V)
   
3. Full-Scale Output Voltage = sensor’s maximum output voltage (e.g., 5 V, 10 V)
   

Examples

-----------

0–10 V Pressure Transducer

Formula:

Pressure (psi) = (Full-Scale Pressure Range × Measured Voltage) / 10

Example:

For a 100 psi transducer measuring 4 V:

Pressure = (100 × 4) / 10 = 40 psi

0–5 V Pressure Transducer

Formula:

Pressure (psi) = (Full-Scale Pressure Range × Measured Voltage) / 5

Example:

For a 200 psi transducer measuring 3 V:

Pressure = (200 × 3) / 5 = 120 psi

Notes:

1. Some pressure transmitters report in PSI, others in Bar.
2. Always use the unit specified by your sensor model.
   

For sensors with other voltage ranges or output characteristics, consult the sensor manufacturer’s specifications.

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