WPI APOLLO 4000, Инструкция по эксплуатации

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APOLLO 4000
OPERATING INSTRUCTIONS
WORLD PRECISION INSTRUMENTS B-7
• Range . After selecting this submenu the range control screen appears
( Fig. B9 ). The user must select a current range for each sensor channel
within the maximum measured/expected value of the experiment. Proper
selection of the measurement range is very important because the
dynamic range of the instrument is
limited to approximately 1,000,000. This
means that the intrinsic background
noise ( i.e., “noise floor”) is proportional
to the maximum measured value. For
example:
If 10 nA range is selected, then the
noise floor will be approximately 10 nA
divided by 1,000,000 ( i.e., 10 fA).
Conversely, if 10
µ
A range is selected
then the noise floor will be
approximately 10
µ
A divided by
1,000,000 ( i.e., 10 pA).
If an incorrect range is chosen for any
channel, the Apollo 4000 will indicate
this as follows:
Fig. B9
Green (sensor) LED Indication Remedy
Intermittent blinking Current detected by sensor is too high Select a higher range
for the selected range
No Green Light Current detected by sensor is too low Select a lower range
for the selected range
Steady Green Light Sensor is normal and within the selected range No action required
If the user is satisfied with the current setting he can chose
Cancel and
work as previously.