In an ideal world, every place you need to install a transmitter would have easy access to electrical power. But we don’t live in the ideal world, and there are locations where power isn’t readily available, and getting electrical power to those areas can be quite costly.

This was the situation at a local plant, in their flammable fuel storage facility. The site is required to keep a record of the line pressure that supplies water in the event of a fire.

The Problem

The water pipe is located 6 to 7 feet (2 meters) below grade, and the engineers planned to build a vault where they could install and maintain the necessary submersible pressure transmitter.

The planned location is more than 500 yards from any available power source. The signal coming from the pressure transmitter would have to run that distance plus an additional 200 yards to reach the control room.

Not surprising, the trenching cost for an electrical installation was quoted at a five-figure minimum price.

Finding a solution

The project engineer started considering a wireless solution, and then asked, “Can a battery-powered industrial radio also power a two-wire loop-powered pressure transmitter?”

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