This section is not a new category of products. Rather it is a grouping of sensors from our product line that all have a common feature—direct 4-20 mA output. These sensors have transmitters built into them that are powered by, and output to, a PLC. Since they do not require an external transmitter they are very cost effective. In two cases (the dissolved oxygen sensor and ultrasonic level transducer) they can also output a digital Modbus signal. All of them can be powered by an inexpensive 24 VDC power source and read by a panel meter.

They include the pH and ORP sensors that we make and probes that we sourced from a half dozen small manufacturers scattered around the country. Nonetheless there are advantages to keeping the transmitter separate from the sensor. Whether any of the following direct output sensors is right for your application depends on several factors. As the drug commercials say, “To find out if a sensor is right for you consult your sensor doctor–that’s us.”