Large Energy Company Lowers Costs and Reduces Maintenance


One Series Case Study
A large energy company needed to lower costs, reduce maintenance and provide more reliable hydrogen-cooled generators for their customers worldwide. In order to monitor seal oil pressure remotely, provide switch control and be able to instantly view pressure readings, three discrete instruments were needed – a pressure transmitter, a pressure switch and a local gauge. These three instruments were all connected to the same pressure source using the piping tree arrangement to the right.

One Series All-in-One
Counting all of the tubing, elbows, t-fittings and connections to each instrument and the pressure source, potential leak paths quickly became a problem. Not counting block and bleed valves, there were a minimum of 12 threaded connections where the media could leak. The cost of the stainless steel tubing and fittings, the cost of the labor to plumb and leak-test and the maintenance required should clogging or leaking occur were all considered. Adding in the cost of the instrumentation and considering reliability, clearly a better method was needed.


The energy company needed a highly reliable instrument that could evaluate and report its own health status and provide the functions of the three instruments while reducing overall costs. The One Series 1XTXSW model is primarily a digital transmitter with display that includes a programmable electronic switch – a switch, a gauge and a transmitter all-in-one.

All One Series models include a self-diagnostic feature called I Am Working™ that monitors several vital instrument functions and reports health status three ways – locally on the digital display, remotely via the NAMUR NE 43 standard 4-20 mA analog output and using a dedicated discrete switch signal.

The One Series’ I Am Working™ diagnostics watch for potential faults that could render the device unreliable. Unlike other blind instrumentation, the One Series can report detected faults with its own imbedded software, keypad, watchdog timer, power, switch and sensor. For example, if a clog occurs in an impulse line connected to the pressure sensor, the One Series can detect and report this fault before it becomes a larger problem – an undetected fault. In this case, the display will read “PLUG” while the IAW switch opens to fail safely and the 4-20 mA output is forced to 3.6 mA. The PLC or DCS evaluating these outputs then initiates an alarm or shutdown, as appropriate for the plant’s control scheme.

The One Series carries worldwide hazardous location approvals everywhere this company operates. The units of measure are field adjustable, so no matter where in the world these seal oil skids land, the units of measure can be set to the local preference during commissioning.