In this application, a wastewater treatment facility needed to transmit process signals from the Secondary Inflow and Final Effluent to the base station at the Central Building where Primary Inflow is calculated and sent to an Auto-Sampler.
Digging trenches and running wires around the plant to get the 4-20 mA signals to where they needed them would have made this a bigger and more expensive project than they wanted, so they decided to use a wireless signal system which saved them a lot of time, man-power, and cost.
Below is a real life application showing how this wastewater facility used an economical and efficient point to multi-point wireless system to transmit the process signals.
System Overview
Process signals from the Secondary Inflow
and Final Effluent 
are sent to the base station at Location 
where Primary Inflow is calculated and sent to an Auto-Sampler.
PDW90-FN Connected to 4-20 mA Sensor Inside the Building
PDA3900 Yagi Antenna Mounted Outside the Building
Location 1: Secondary Inflow
An existing 4-20 mA sensor from the Secondary Influent is wired to a PDW90-FN field unit inside the building. Coax cable is run through the wall to a Yagi antenna mounted outside. The signal path is 500' and goes through the trees.
PDW90-FN Connected to 4-20 mA Sensor Inside the Building
PDA3900 Yagi Antenna Mounted Outside the Building
Location 2: Final Effluent
The 4-20 mA sensor from the Final Effluent is connected to a PDW90-FN field unit inside the building.
Coax cable is run through the wall to the antenna mounted on the roof. The signal path is 150' and goes through another building.
Yagi Antenna connected to the PDW90 Base Station
PDW90 Base Station, ConsoliDator+ Controller, and Auto-Sampler
PD9000 ConsoliDator+ Multivariable Controller Display
Location B: Primary Effluent
The base station antenna receives signals from locations & , then sends 4-20 mA signals to the PD9000 multivariable controller which subtracts the Secondary Inflow from the Primary Effluent to calculate the Primary Inflow occurring at this spot.
The Calculated Primary Inflow value is then sent to the auto-sampler.
All the process values are logged to the included USB drive on the ConsoliDator+ Controller.
Learn more about the PDW90 wireless products used in this wastewater application and more below:
