Unipulse F805AT-BC, Operation Manual

Page: 145 / 202

8.INTERFACE
130
・
D/A zero and span adjustment
（
1
）
Zero (4mA) adjustment
・
Press or to select a channel.
・ Press . Current output (approx. 4mA) starts to flow.
・ Enter the reading of the external current meter using the keypad, and
press .
・
F805AT-BC automatically adjust the deviation between the nominal (4mA) and
actual values.
“Registered” message appears when the procedure is complete.
（ 2 ） Span (20mA) adjustment
・ Press or to select a channel.
・
Press . Current output (approx. 20mA) starts to flow.
・ Enter the reading of the external current meter using the keypad, and
press .
・ F805AT-BC automatically adjust the deviation between the nominal (20mA) and
actual values.
“Registered” message appears when the procedure is complete.
* Span (20mA) adjustment may give rise to a slight shift in zero (4mA) output level,
and vice versa. Press to verify the accuracy of zero adjustment. If a slight
shift in zero output is observed, repeat the zero adjustment procedure again. Check
also the integrity of the span after the zero adjustment. A few times of repeated
adjustment may be required until a well converged zero and span adjustment will be
obtained.
* After both parameters are successfully registered, turn off the F805AT-BC and
turn on again to return to the normal screen.
Selected channel
Output
Adjusting parameter
Message
Note:
Do not try to fine-adjust the D/A converter unless a reliable measuring device
(e.g. current meter) is at hand. Once improper parameter modifications have
been done, the F805AT-BC may not be able to be restored to its factory-
configured state.
(user input)
ch1 ch2
4mA
OK
ch1 ch2
20mA
OK
4mA