Keith Bowden St. John Medical of Newfoundland, Canada needed a way to demonstrate that the installation of the hospital's new emergency generator would shorten the transmission time between power failures and initialize the equipment's backup emergency diesel generator.
Why is this so important? In medical situations, hundreds of people may rely on power to operate equipment to provide their health needs, from intravenous feeding to cardiac monitoring of oxygen intake to ongoing surgery. Electricity is their lifeline.
The hospital estimated that between 15 and 30 seconds after the utility outage occurred, the emergency generator began to fail. The passage of time, however, is often over disputes. With no one constantly monitoring the generators, and with the uncertainty of the outage itself, it's difficult to determine exactly how much time has passed.
Bowden Reviews Several Loggers HOBO® U9-004 (New Models UX90-004, UX90-004M) Motor On/Off Data Logger, U9-001/UX90-001, UX90-001M Lighting Status Logger, UX90-002 , UX90-002M (old model U9-002), UX120-017, UX120-017M and monitoring systems to verify transfer times, but they are too expensive or do not have the required memory. He also needs accuracy +/- within 1 second.
In the end, Bowden chose HOBO® U9-001/UX90-001, UX90-001M from Onset. These are compact, battery-operated devices that record on/off state changes, and store time, data and status information for each change. Four data loggers are attached to each of the hospital's three substations, and another for each area of the diesel generator itself showing on/off status U9-004 (new models UX90-004, UX90-004M). During the first outage, the loggers were able to record the time from normal power going until their new emergency generator started providing power. Once the data is collected, it is transferred to a computer and analyzed using Emerge's Wagon Compartment® graphing and analysis software. The transmission time of the hospital's emergency care area, including the operating room, intensive care, etc. is only 11.5 seconds, and the transmission time of the hospital's other two substations is 14 seconds. With this data, Bowden was able to easily and efficiently verify the reduction in transmission time of the new generator.
"HOBO status loggers UX90-001, UX90-001M, UX90-004, UX90-004M, UX120-017, UX120-017M are good for this type of application," said Bowen. "These units will remain on-line permanently to record transfer times from normal to emergency power during any future interruptions."
