ZERO RNGE
(zero range)
The zero range function allows a limit value to be set (in engineering units) above which the display
will not zero i.e. if a zero operation is attempted via the
P
button, remote input or set zero function when the
display value is greater than the zero range setting the display will refuse to zero and give a
ZERORNGEErr
message (note that the
CAL OFSt
function is also affected by the
ZERO RNGE
setting). For example if the
zero range setting is 10 the instrument will only respond to a zero operation if the display reading at the time is
between -10 and 10. If the zero range function is not required it can be set to
OFF
by pressing the
^
and
v
buttons simultaneously at this function. When switched off the instrument can be zeroed no matter what the
display value.
Note that the instrument keeps track of the value being zeroed at each operation, when the total
amount zeroed from repeated operations becomes greater than the zero range value the instrument will
reject the zero operation and a
ZERO RNGE Err
message will be seen. To allow a zero operation beyond
this point either the
ZERO RNGE
function value will need to be raised or a new zero reference point
introduced via the
CAL ZERO
function.
If repeated zero operations are required the
ZERO RNGE
function should be set to
OFF
or
alternatively the
tARE
operation could be considered.
CAL ZERO
(calibration zero)
The calibration zero function is used following a calibration via
CAL1
and
CAL2
. A calibration zero
operation at this time ensures that the display zero and the
ZERO RNGE
reference zero are at the same
point after a calibration. After a calibration the calibration zero can also be used to select a zero point other
than the display zero as the reference for the
ZERO RNGE
function. For example if the
CALZERO
operation
is carried out with a display reading of 500 and a
ZERO RNGE
reading of 10 the zero range function will allow
the display to zero only if the current display reading is between 490 and 510. To perform a calibration zero
press the
^
and
v
buttons simultaneously at the
CALZERO
function, a live reading will be seen, press the
F
button, the message
CAL ZERO End
should now be seen indicating that the instrument has accepted
the zero point. Although the display reading will not change as a result of the calibration zero the input value
on the display at the time of the operation will be the new zero reference point for the
ZERO RNGE
function.
USER En 4
(4mA input scaling without a live input)
This calibration method can be used with 4-20mA inputs only. The instrument can be scaled for a
4-20mA input without a live input i.e. this is an alternative method to the
CAL1
and
CAL2
method of scaling.
To perform the first point (
En 4
) scaling simply press the
^
and
v
buttons simultaneously when the
USER
En4
function has been reached. The display will now indicate a value. Use the
^
or
v
button to change this
value to the scale value required for a 4mA input. Once the
USER En 4
scaling has been completed, the
USER En20
function should be completed, see below.
USER En20
(20mA input scaling without a live input)
This calibration method can be used with 4-20mA inputs only. The same method described in
USER
En4
above can be used to scale the instrument for a 20mA input. Again use the
^
or
v
button to change the
value displayed to the scale value required for a 20mA input.
Example
:
If the 4-20mA input is to be scaled so that the display reads
0
at 4mA and
5000
at 20mA
then
USER En4
should be set to
0
and
USER En20
should be set to
5000
.
UCAL
(uncalibrate)
Used to set the instrument back to the factory calibration values. This function should only be used
when calibration problems exist, and it is necessary to clear the calibration memory. To reset the instrument
calibration press
^
and
v
together at the
UCAL
function. The message
CAL CLr
should be seen.
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