Compare this temperature with the temperatures listed on the probe calibration
report toverify that the coefficients you entered are correct.
6.5 Filtering
Whilemeasuring temperature, the readings may appear to vary. This may be
due to actualvariations in temperature or electrical noise internal to the 1502A.
The filterhelp s to smooth variationsin the measur ements and improveresolu-
tion. The drawbackis that filtering tends to slow the response to changes in
temperature. Youcan increase the filter time constant to further improve accu-
racyand resolution or decrease the time constant to reduce the response time.
Youcan set it to any value between 0 and 60 seconds. A value of 0 disables the
filter.The default time constant is 4 seconds.
Tochange the filter value, enter the Sample menu. This is done by first press-
ing the Menu button (“SEt?” appears) then pressing the F/Sample button.
The display will briefly indicate “SA Par”, then “FILtEr”, then the current
filtervalue. Use the Uand Dbuttons to in crease or decrease the filter value
then press Enter.The next parameter in the menu, the current, will then appear.
6.6 Setting the Current
Youcan select one of two options for the probe excitation current: 1.0 mA (de-
fault) or 0.5 mA. The current is set within the Sample menu. Press the Menu
button (“SEt?” appears) then press the F/Sample button. The filter value will
appear.Press Enter to continue. The display will briefly show “CurrEnt”
followedby the value for the current. You can use the Uand Dbuttons to
change the valuefor the current. Press Enter to continue.
6.7 Power Saver
The powersaver feature causes the display to blank after a period of no user ac-
tivity.The power saver feature can reduce operating current by as much as 100
mA. While the display is blanked a small illuminated dot appears on the left
side of the display as an indication thatthe 1502A is still operating. Pressing
anybutton on the front panel restores the display. You can program the power
saverto activate after a specified period of time from 5 minutes to 60 minutes
in intervalsof 5 minutes. You can also disable the power saver feature com-
pletely.The power saver is off by default.
The powersaver is programmed in the Sample menu. Press the Menu button
(“SEt?”appears) then press the Sample menu button.Press Exit tw ice to skip
to the powersaver parameter. The display will briefly show “PO SA” followed
by the powersaver setting. You can use the Uand Dbuttons to change the
powersaver period (in minutes) or set it to OFF. Press Enter to continue.
1502A Thermometer Readout
User’s Guide
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