Fluke Biomedical 07-487 - Manual (Page 10)

Nuclear Associates 07-487
Operators Manual
2-2
2.4 Over-Range Indication
Following the calibration process, repeat the injection of mAs signals without resetting. Note that the “+”
sign should appear at 1600 (160.0) mAs and above and should remain on when total mAs value exceeds
2000 (200.0) mAs, 3000 (300.0) mAs.
2.5 LO BAT Indication
A quick test demonstrates the action of the LO BAT circuit: short circuit R8 (also U6 pin 2 to U6 pin 4) and
note that the “LO BAT” display appears. A more precise test uses an adjustable power supply in place of
the 9 V battery. Slowly reduce the voltage and observe when “LO BAT” appears. It should first appear
when the external power supply is between 7.7 and 7.3 volts and must remain displayed as the voltage is
decreased to less than 5.0 Volts. In general, the “LO BAT” will remain displayed until the entire display
fades out. Note: mAs readings taken when the “LO BAT” appears may not be valid.