Chapter 3 Principle of Operation
50 Gem-5 User’s Manual
During periods when no occupant is being monitored (and when no one is detected in
the vicinity of the monitor by the approach sensors), the unit takes the background
count for each individual detector, averaged over the time period set in the F2 – Wait
Timeouts setup screen. After correcting for efficiency, it calculates the minimum time
needed to count an occupant to ensure an accurate clean/contaminated decision for
the specified alarm release level. Decisions are based on the background count rate
for each detector and the specified confidence levels for alarms and false alarms, as
preset in the F1 – Zone Configuration screen. The actual count time is also held
within acceptable limits by the maximum and minimum monitor times set in the Wait
Timeouts screen.
Extensive records are maintained for monitor, background and service histories as
well as detailed contamination results. Refer to the F7 – Data Log setup screen, the
F5 – Information service menu options and the F6 – Printout setup screen.
The text that appears on the Ready, Position, Turn, Clean, Contaminated, Frisker,
Out-of-Service and Messages screens is configurable using the F11 – Operation
Instruction setup menu options.
The monitor continuously checks for proper operation of all components and can
report operational status to a remote computer loaded with the optional CRemote
software over a LAN communication network. It can also transfer results data to a
file or a printer (if connected).