BEKA BA574C, Руководство пользователя

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The calibration is performed using the internal
references and may be made with any transmitter
input voltage.
Select 'In-HI' from the menu and press P which will
access a sub-menu containing two functions 'InPut'
and ''dISP'.
Select the input voltage 'InPut' and press P which
will cause the specified higher input millivoltage to
be displayed in the form XX.XX The flashing digit of
the input voltage can be changed by pressing the
Up or Down buttons. When the first digit is correct,
pressing P will transfer control to the next digit.
When the least significant digit has been adjusted,
press
E to return to the 'InPut' prompt, from which
the display prompt 'dISP' can be selected by
pressing the
Up or Down button.
Pressing P will reveal the transmitter display
corresponding to the specified higher input voltage.
The position of the dummy decimal point will be as
defined by function 'd.P.' - see section 5.5.1
The flashing digit of the display can be changed by
pressing the
Up or Down buttons. When the first
digit is correct, pressing P will transfer control to
the next digit. When the least significant digit has
been adjusted, press
E to return to the ''dISP'
prompt.
5.6 4/20mA output current calibration 'CAL'
This sub-menu defines the relationship between the
transmitter display and the 4/20mA output current.
The transmitter output current is derived from the
transmitter display and will change if the display
calibration is changed. 'ZEro' defines the display
at which the output is 4mA, and 'SPAn' the display
at which the output is 20mA.
To calibrate the output current select 'CAL' from the
programme menu and press
P which will access a
sub-menu containing two functions. Select 'ZEro'
and press
P which will show the transmitter display
at which the output current is 4mA. The flashing
digit of the display can be changed by pressing the
Up or Down buttons. When the first digit is correct,
pressing P will transfer control to the next digit.
When the least significant digit has been adjusted,
press
E to return to the 'ZEro' prompt, from which
the span prompt 'SPAn' can be selected by
pressing the
Up or Down button.
Press P to show the transmitter display at which
the output current is 20mA. The flashing digit of the
display can be changed by pressing the
Up or
Down buttons.
When the first digit is correct, pressing P will
transfer control to the next digit. When the least
significant digit has been adjusted, press
E to
return to the 'SPAn' prompt.
Note: If a complete loop including a primary
element, BA574C temperature transmitter and a
load are being calibrated, the Trim Menu is the
preferred method. It allows the transmitter display
and output current to be adjusted to compensate
for inaccuracies. Details of the trim menu are
contained in section 6 which also describes periodic
calibration.
5.7 Security Code 'COdE'
Access to the Programme and Trim Menus may be
protected by a four digit numerical security code
which must be entered before access is granted.
New instruments are programmed with the default
security code 0000 which allows unrestricted
access to both menus.
To enter a new security code select 'COdE' from
the programme menu and press
P which will cause
the transmitter to display the current security code.
Each digit of the code can be changed using the
Up
and Down push-buttons, and the P button to move
to the next digit. When the required code has been
entered press
E to return to the main menu. The
revised security code will be activated when the
transmitter is returned to the display mode.
If the security code is lost, access to the
programme and trim menus can be obtained by
putting the security link in the override position - see
Fig 6. The security code can then be viewed by
selecting 'COdE' from the menu and pressing
P .
Fig 6 Location of security code override link
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