Electrical Fault of Control Element Drive Mechanism

Calvert Cliffs, MD Power Reactor 1-14-00 @ 0950 EST Event # 36951 | ELECTRICAL FAULT OF CONTROL ELEMENT DRIVE MECHANISM MOTOR GENERATOR SET | | (CEDM MG SET) CAUSES A REACTOR TRIP. | | | | The reactor automatically tripped, and all rods fully inserted into the | | core. Preliminary indication is that CEDM MG set #11 had an electrical | | fault which caused a reactor trip bus undervoltage condition which picked up | | the undervoltage relays which tripped the main turbine which caused the | | reactor trip. One of the second stage steam supply valves to the moisture | | separator reheater failed to close automatically (because the electrical | | breaker for the valve opened) which required the licensee to close the main | | steam isolation valves (MSIV). The licensee is maintaining no load T(ave) | | temperature by dumping steam to the atmosphere via the steam generator | | atmospheric valves and feeding the steam generators with one of the | | motor-driven auxiliary feedwater pumps. Neither of the steam generators | | have any leaking steam generator tubes. The licensee is making preparation | | to open the MSIVs. All emergency core cooling systems and the emergency | | diesel generators are fully operable if they are needed. The licensee | | stated that the electrical grid is stable. | | | | The licensee is investigating the event. | | | | The NRC resident inspectors were notified of this event by the licensee. | +--------------------------------------------------------------------- link: http://www.nrc.gov/NRR/DAILY/der.htm

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Failure of Interlock Merck Co, Inc. West Point Region, PA 01-14-00 1000EST Event # 36953 FAILURE OF INTERLOCK DISCOVERED DURING NORMAL MAINTENANCE CHECKS | | | | During the performance of annual preventative maintenance checks, a | | technician discovered that one of the interlocks was not functioning. The | | interlock prevents the source from being raised or exposed with the shield | | doors open to protect the operator. The device is a J. L. Shepherd Mark-1 | | Model 30-1 irradiator. The irradiator has been tagged out of service until | | serviced by the vendor. The room contained audible and visible alarms that | | were functional, thus any operator would have been alerted if the source had | | become exposed. | | | | The vendor, J. L. Shepherd, has been contacted and expects to have a | | technician on site next week. | | | | (Call the NRC operations officer for a contact telephone number.) | link: http://www.nrc.gov/NRR/DAILY/der.htm +------------------------------------------------------------------------------+ *************************************************************** Possible Computer Problem with High Dose Remote Applicator Utah Division of Radiation Control Salt Lake City Region, Utah 01-11-00 POSSIBLE COMPUTER PROBLEM WITH HIGH DOSE REMOTE APPLICATOR (Utah Report | | #00-0001) | | | | This is a preliminary report of a possible problem existing with the | | computer for a Nucletron Corporation, Model 105.999, MicroSelectron-HDR, | | version 2, remote afterloader brachytherapy device, serial #31062, that | | could lead to a medical misadministration. This device is located at the | | University of Utah Medical Center. The problem is being investigated by the | | vendor, and the problem is thought to be a CPU communication fault. The CPU | | has been sent to the manufacturer for further testing. | | | | Utah has contacted the State of Maryland as well as Nucletron Corporation. | | | | (Call the NRC operations officer for a contact telephone link: http://www.nrc.gov/NRR/DAILY/der.htm

-- boop (leafyspurge@hotmail.com), January 19, 2000