measurement error due to ther esistanceof the wires. With four wires the in-
strument can completely cancel the error.The internal measurement circuit is
configureddifferently depending on the number of wires.
Note: The instrument triesto calculate a measurement evenif the wire settings
are incorrect. Therefore, the Probe Wiressetting mu stm atch the actual number
of wires or loss of accuracywill result (see Section 6.6). Use the Up and Down
buttonsto set the value and press the ENT button to store and continue.
7.9.15 PCal
This function shows the date the probe was calibrated and allows it to be set.
The dateis stored in the INFO-CON connector and is used simply for refer-
ence. Use the Up and Downbuttons to set each date segment and the ENT but-
ton to moveto th e nextdate segment to the r ight. Press ENT when the date is
correctly entered. Press CLR to moveto the next function without changing the
date.
7.9.16 PDue
This function shows the date the probe is due for calibration and allows it to be
set. The dateis stored in the INFO-CON connector. The probe due date is regu-
larly checkedagainst the present date and if the calibration has expired the user
is alertedwith the message “Prb cal expired”. The message disappears only
when the probe is recalibrated and the probe calibration due date is set to a fu-
ture date. Toset the date use the Up and Down buttons to set each date segment
and the ENT button to moveto the next date segment to the righ t. Press ENT
when the date is correctly entered. Press CLR to moveto the next function
withoutchanging the date.
If anyof the parameters in the CAL Mode were changed, the message “Up-
loading params” is displayed when exiting the PDue parameter. After the pa-
rametershave been uploaded into the INFO-CON connector, the meter
advancesto the next menu item.
7.9.17 Digital Filter
The digital filterh elps to smooth variationsin th em easurements and improve
resolution. A negativeeffect of filtering is that it tends to slow the response to
changes in temperature. Youcan increase the filter time constant to further im-
proveaccuracy and resolution or decrease the time constant to reduce the re-
sponse time.Valid values are any number between 0.0 and 60.0 seconds. A
valueof 0 .0 disables the filter.The default is 0.0. Use the Up and Down but -
tonsto set the value and press the ENT button to store and continue. Press
CLR to moveto the next function without changing the filter.
7.9.18 MCal
This function shows the date the instrument was calibrated and allows it to be
set. The date isu sed simply for reference. Use the Up and Downbuttons to set
45
7 Display Functions
CAL MODE