Further tests were done on the active sump high level float switch today. The switch was triggered 1 time by filling the sump, and approximately 8 times by tilting the sensor manually. A local alarm sounded in the hot cell lab each time, but only one time in the RCR Lab and MCR (this occurred on the final trial). Fault report #9099 has been submitted to Controls Group. Although the existing float sensor did cause a local alarm when the sump was filled, it's operation did not seem ideal: it only triggered when completely horizontal, which wasn't until water was several inches above the base of the switch; in addition it appeared that it may be possible for the switch to become stuck under the horizontal portion of the sump (possibly even in an untriggered orientation). For these reasons a replacement level switch will also be investigated.
UPDATE (Sept 8, 2016): Further testing revealed that the electronics for the high level switch were wired incorrectly which resulted in the RCR PLC only seeing sump level high when the "silence" button on the electronics box for the switch was pushed. This was not discovered during previous tests because the "silence" button was pushed each time shortly after triggering the switch. The new electronics for the switch will address this issue. |