We met with Mr. Tanaka of the Production Management Division who is in charge of all planning, installation, and implementation of measuring equipment in the factory.
The factory we visited uses utility boilers that are monitored with the DX200 Paperless Recorder, UT351/UT550 Digital Indicating Controllers, and the DA100 Data Acquisition Unit.

Mr. Tanaka: "We manage the boilers with one of the DA100 and two of the DX200s. One of the DXs monitors the nitrogen gas, and the other monitors the steam. Nitrogen and steam are each controlled using flow meters at the inlets to the plant, and all signals from those flow meters are centrally monitored in the utility room. Along with that we take integrals of the instantaneous flow and display and record all the data on the DX. We've set them up to accept alarm input, so that a phone call is received on the factory internal or external line any time an alarm occurs."

Nippoh originally used 3-pen recorders and dot recorders to monitor fuel gas and steam pressure, but gradually needed to monitor current consumption which was difficult to do with their current system. Therefore they brought in the DX200, which they are still using today. At the same time, they started using DAQLOGGER data acquisition software, and can now load all the data from both DX200s and the DA100 for centralized monitoring.

Mr. Tanaka: "The DX gives us high speed data capture, multichannel functionality, and it also doesn't require paper. Those were the reasons we chose it."

"Paper is paper, and has the advantage of being able to represent the data quickly and clearly, but electronic data is very convenient because we no longer have to worry about storing and replacing chart paper and ink. Two times a year we copy the recorded electronic data from the flash memory to a PC and burn a CD to store the data. Also, it's easier to manage the system now because we can monitor the data centrally using DAQLOGGER and see all the conditions at a glance."

Nippoh controls steam pressure using the UT351/UT550 (Digital Indicating Controller). Mr. Tanaka's first impression of the UT was, "I had no idea it was this powerful."
The people managing the boilers are responsible for decreasing steam pressure or supplying steam to each of the lines as needed. If a problem with steam pressure occurred, it used to be necessary for a person to go to each line, close the valves, and then reopen the valves again after the problem was resolved.

Mr. Tanaka: "Now when an abnormality is detected an alarm is output, the people in charge are notified by an auto-reporting system, and at the same time, the UT adjusts the steam pressure valves and closes them in stages. When this happens, the UT550's zone PID function can be used to have the valves opened or closed by some percentage in steps of one or two minutes. This is a really useful function for us. Up to now it took a person 2 hours to do this, but now the job can be done fully automatically in fifteen minutes. This gives us a wholesale improvement in efficiency."

These are examples of how the UT series' alarms (including use as events), network functions, and zone PID functions are being put to good use.

Nippoh Chemicals is also using many other Yokogawa products including the CENTUM product control system, the EJ series of differential pressure transmitters, and the digital YEWFLO overflow meters.