Pacific Scientific 5170, Инструкция по эксплуатации

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AUTOMATIC ZERO FUNCTION
The meter provides two methods to zero the probe. The first is completely automatic. Prepare the probe for zeroing,
then press the ZERO pushbutton. The “ZERO” icon will flash and actual dc flux density readings will appear on the
display. If the reading before zeroing the probe exceeds ±30 mT (300 G or 23.88 kA/m) when the probe is in a zero
chamber or very low field, then the probe may be defective. The meter will switch over to the DC mode of operation
during zeroing. Recall that the zeroing operation affects DC offsets only. If you wish to suppress an AC field reading
consider using the RELATIVE mode.
Once automatic zeroing begins it must be allowed to complete. During this time all controls are disabled except for the
POWER switch. The process normally takes from 5 to 15 seconds.
The meter selects the lowest range and adjusts the nulling signal until the net result reaches zero. At this point the
automatic process is terminated and the flashing “AUTO” and the "ZERO" icons will disappear.
If the nulling process is successful, the next highest range is selected. No further electronic adjustments are made, but
at this stage a reading is acquired which will be mathematically subtracted from all future readings on this range. This
process is then repeated for the highest range. When finished, the meter will sound an audible beep and the flashing
“AUTO” and “ZERO” icons will disappear. At this point the automatic process can be repeated or a manual adjustment
can be performed (see “Manual Zeroing”).
The final zero values will remain in effect until the meter and probe are zeroed again.
NOTE:
Zeroing the probe cancels the RELATIVE mode if it was turned on.
Figure 3-14
Automatic ZERO Function
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