Running around the plant…
Most automated industries have a lot of pressure monitoring, where operators go out to check measurements, make notes, and inform their control rooms about process conditions.
You know those operators spend a lot of time doing all that. Why should they spend all that time when it’s easier to send the information directly to the control room? There you can build a history of the whole day, month, and year.
You’ll also get more accuracy if your devices send their data directly to the control room. Field operator can make mistakes reading or noting process values. You also only get the value from the device at that point in the cycle, losing any data from before and after the operator check.
The transparent solution…
So how do we improve our process? Go wireless. To begin with, it makes for a surprisingly cheap upgrade because you don’t need to spend money on cables, structure, or service.
Even better, most wireless devices have their own power supply, creating a mesh network to send all information to the gateway. Although the gateway can cost a little more, it can also support up to 250 devices. Keep in mind, however, that the update time will factor into the number of devices in your network.
A real experience…
With all that said, it should seem logical to use wireless, but some companies still don’t because they lack faith in its security.
I once visited a chemical company that wanted new technology for their plant, primarily their pH sensor and pressure monitoring system for their pumps. We proposed a wireless device for the pressure monitoring system, saving money on the installation. For the pH sensor, we suggested wireless combined with plant asset management to monitor the sensor health.
Unfortunately, they rejected our advice because their company believed that wireless is not a secure protocol. Nothing would convince them otherwise.
They had 4–20 mA, with an operator routine, to check the pH sensors and pressure transmitters. Wireless could improve their process monitoring, but for that, they need to open their minds to the idea.