BEKA BA678C, Руководство пользователя, Страница: 18 / 27

7. CONFIGURATION EXAMPLE
In this example a BA678C indicating temperature
transmitter is required to display temperature in
degrees Celsius with maximum resolution. The
temperature sensor is a 3 wire Pt100 resistance
thermometer and the 4/20mA transmitter output is
required to representing –10 to +250
o C. . A left hand
justified bargraph representing 100.0 to 200.0 o C is
required. Resistance thermometer failure is to be
indicated by an overrange output current of 21.0mA.
After configuration access to the configuration menu
is to be protected by code 1209.
Configuration is performed using the front panel push
buttons – see Fig 3.
The transmitter configuration may also be performed
via HART

communication from a local or remote
configurator. The HART

communication protocol
includes additional functions allowing the complete
temperature loop, including the temperature sensor
and the transmitter load, to be calibrated - see the
BA47X/67X
Indicating Temperature Transmitter
HART

Interface Guide which may be downloaded
from www.beka.co.uk/manuals
Step 1 Access the configuration menu &
select the type of input.
See: Fig 6 and section 6.2.1
New BA678C indicating temperature
transmitters are supplied conditioned
with default access code ‘0000’ that
allows
unrestricted access to the
configuration menu.
To enter the configuration menu press
buttons
P and E simultaneously which
will cause the first prompt ‘InPut’ to be
displayed. Press
P to enter the function
and the transmitter will display the
current type of input.
To configure the
transmitter to operate with a three wire
resistance thermometer press the
▼ or
▲ button until ‘3rtd’ is displayed. When
selected press E to enter the selection
and return to the ‘InPut’ prompt in the
configuration menu.
Step 2 Select resistance thermometer type
See: Fig 6 and section 6.2.10
Using the
▼ or ▲ button select the
‘r,tYPE’ prompt from the configuration
menu and press
P to enter the function
which enables the type of resistance
thermometer
to be selected. The
transmitter will display the existing type
of resistance thermometer, using the
▼
or ▲ button select ‘100r’ which is the
required Pt100 sensor. Enter the
selection by pressing the E button that
will return the display to the ‘r.tYPE’
prompt in the configuration menu.
Step 3 Select units of digital display
See: Fig 6 and section 6.2.3
Using the
▼ or ▲ button select ‘dEG’
from the configuration menu and press
P to enter the function which enables
the digital display units of measurement
to be selected. Using the
▼ or ▲ button
scroll through the options and select ‘ºC’
which
represents degrees Celsius.
Press E to enter the selection and return
the transmitter display to the ‘dEG’
prompt in the configuration menu.
Step 4 Select display resolution
See: Fig 6 and section 6.2.4
Using the
▼ or ▲ button select ‘rESn’
from the configuration menu and press
P to enter the function which determines
the resolution of the digital display.
Using the
▼ or ▲ button select ‘Hi’ to
provide the required 0.1 resolution
display. Press
E to enter this selection
and return the display to the ‘rESn’
prompt in the configuration menu.
Step 5 Sensor fault detection
See: Fig 6 and section 6.2.6
Using the
▼ or ▲ button select ‘FAuLt’,
the input sensor fault detection function,
from the configuration menu and press
P . Using the ▼ or ▲ button scroll
through the options and select ‘uP 21’
which forces the output current to
21.0mA when a sensor failure is
detected.
Enter the selection by
pressing E which will also return the
transmitter display to the ‘FAuLt’ prompt
in the configuration menu.
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