Hawk, a leading global provider of level, positioning and flow measurement technology, has begun using the HawkLink interface to communicate with Hawk devices via cell phone networks or the Internet.
“We want people to know that we can help them with commissioning and startup, and we don’t have to be physically at their location,” said Jack Evans, president of Hawk Measurement USA.
A HawkLink unit collects inputs from Hawk sensors and switches, and relays them to Hawk’s central server. The connection between the HawkLink and the server can be made via a cell phone network or over the Internet. At the other end of the link, a technician can log onto the server using a PC running GosHawk software and watch the inputs from the Hawk devices changing in real time. The HawkLink can transfer data in both directions, so the technician can also change the calibration and setpoints on the Hawk devices.
“Recently we were working with a major steel manufacturer,” Evans explained. “They use large amounts of carbon black, a very light powdered material. During filling, the air inside the tank becomes extremely dusty, and it’s difficult to measure the level accurately. We sent them a HawkLink unit, and we were able to watch the fill and draw cycles from our office. If we had to send a man out there for a week, that would have been expensive for us or for our customer. It’s a lot simpler to just send them a HawkLink.”
Normally, a HawkLink unit is used only during the commissioning and setup of the Hawk sensors or controls. Each HawkLink unit is configured before it is sent to a customer, so all of the details of the cell phone or Internet connection are worked out in advance. To complete the connection to the device being monitored, the customer needs to connect just two wires.
To communicate with the Hawk devices, the HawkLink can handle signals via MODBUS/RS485. When connecting with the “outside world,” the HawkLink can communicate using the CSD protocol over GSM and CDMA cell phone networks. When connecting via the Internet, the unit can use the GPRS protocol (TCP/IP) over a GSM system.
Evans noted that customers often want to keep a HawkLink in place after the setup process is complete. “In fact, our biggest problem is getting these back from our customers,” he added.