BEKA BA478C User manual

Issue 8
27th February 2015
BA478C
Intrinsically safe
panel mounting
indicating temperature
transmitter
Issue 8

2
1. Description
2. Documentation
3. Operation
3.1 Controls
4. Intrinsic safety certification
4.1 ATEX certificate
4.2 Zones, gas groups & T rating
4.3 Special conditions for Zone 0 installation
4.4 Certification label information
4.5 Input terminals 1, 2, 3 & 4
4.6 4/20mA output – terminals 5 & 6
5. Electrical system design
5.1 Use with Zener barriers
5.2 Use with galvanic isolators
5.3 Use as a temperature indicator
6. Installation
6.1 Location
6.2 Installation procedure
6.3 EMC
7. Configuration
7.1 Configuration menu
7.1.1 Access
7.1.2 Summary of functions
7.2 Description of configuration menu functions
7.2.1 Transmitter input ‘InPut’
7.2.2 Thermocouple type ‘t.tYPE’
7.2.3 Units of digital display ‘dEG’
7.2.4 Display resolution ‘rESn’
7.2.5 Cold junction compensation ‘CJC’
7.2.6 Sensor fault analogue indication ‘FAuLT’
7.2.7 Configuration of 4/20mA output ‘CAL’
7.2.8 Configuration of bargraph display ‘bAr’
7.2.9 Access code ‘CodE’
7.2.10 Resistance thermometer type ‘r.tYPE’
7.2.11 Decimal point position ‘dP’
7.2.12 Lower input & display ‘in-Lo’
7.2.13 Higher input & display ‘in-Hi’
7.3 Configuration defaults
8. Configuration example
9. Maintenance
9.1 Fault finding during commissioning
9.2 Fault finding after commissioning
9.3 Servicing
9.4 Routine maintenance
9.5 Guarantee
9.6 Customer comments
10. Accessories
10.1 Scale marking
10.2 Tag number
10.3 Alarms
10.3.1 Solid state output
10.3.2 Intrinsic safety
10.3.3 Alarm configuration
10.3.4 Alarm selection ‘Alr1’ & ‘Alr2’
10.3.5 Alarm enable ‘EnbL’
10.3.6 Setpoint adjustment ‘SP1’
10.3.7 Alarm function ‘’Hi.Lo’
10.3.8 Alarm output status ‘no.nC’
10.3.9 Hysteresis ‘HStr’
10.3.10 Alarm delay ‘dELA’
10.3.11 Alarm silence time ‘SiL’
10.3.12 Access setpoint ‘ACSP’
10.3.13 Adjusting alarm setpoints from
operational mode.
Appendix 1
FM Approval for use in the USA and
cFM Approval for use in Canada
Appendix 2
IECEx certification
CONTENTS
The BA478C is CE marked to show compliance with the European Explosive Atmospheres
Directive 94/9/EC and the European EMC Directive 2004/108/EC

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1. DESCRIPTION
The BA478C is a panel mounting, intrinsically safe
4/20mA loop powered temperature transmitter with a
large easy to read display. The instrument, which is
HARTenabled, may be conditioned on-site to
operate with most common thermocouples and
resistance thermometers and will provide a linear
4/20mA output proportional to temperature, plus a
digital temperature display. Voltage and resistance
inputs may be scaled allowing the BA478C to display
variables other than temperature such as position
and weight.
Optional factory fitted alarms provide two galvanically
isolated solid state outputs that may be
independently configured for high or low operation.
For installation in poorly illuminated areas, an
optional factory fitted loop powered display backlight
is available.
The BA478C has been certified intrinsically safe for
use in flammable gas atmospheres by European
Notified Body Intertek Testing and Certification Ltd
(ITS) and complies with the ATEX Directive 94/9/EC.
For international applications, the BA478C has FM,
cFM and IECEx intrinsic safety certification – see
Appendix 1 and 2.
Fig 1 Simplified block diagram
2. DOCUMENTATION
This instruction manual describes the installation and
configuration of the BA478C Indicating Temperature
Transmitter for ATEX intrinsically safe applications.
System design information for IECEx and other non-
ATEX certifications are included in separate
appendices to this manual. The transmitter is HART
Registered and is compliant with HART protocol
standard revision 7. HARTcommissioning
information is included in the BA47X/67X Indicating
Temperature Transmitter HARTInterface Guide
which may be downloaded from
www.beka.co.uk/manuals
3. OPERATION
Fig 1 shows a simplified diagram of the BA478C
Indicating Temperature Transmitter. The input,
which may be from a resistance thermometer,
thermocouple, or a dc voltage or resistance, is
digitised and transferred to the instrument processor
via an optical isolator. The processor linearises the
input signal, displays the resulting temperature in the
selected units and controls the 4/20mA output
current.
3.1 Controls
All functions of the transmitter may be configured via
the six front panel push buttons – see Fig 5.
Buttons respond within 0.5 seconds of being
operated and unless continuously pushed the
transmitter display will return to the operating mode
after 2 seconds.
In the operational mode, i.e. when the transmitter is
displaying the input signal, these push buttons have
the following functions:
Button Function
While this button is operated the transmitter
will show the display corresponding to 4mA
output.
▲While this button is operated the transmitter
will show the display corresponding to
20mA output.
+Transmitter displays output current in mA
followed by output as % of the range.
P + Transmitter displays HARTshort address
followed by firmware version number.
P + EEntry to configuration menu.
When fitted with optional alarms
P + Entry to alarm set point menu. See 10.3.12
E + Transmitter displays alarm 1 setpoint
E + Transmitter displays alarm 2 setpoint
P Activated alarm reverts to the non-alarm
condition for the configured alarm silence
time. See 10.3.11

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4. INTRINSIC SAFETY CERTIFICATION
The BA478C Indicating Temperature Transmitter is
intrinsically safe allowing installation in Zone 1 or 2
when protected by a safe area Zener barrier or
galvanic isolator. It may also be installed in Zone 0
if special conditions are observed – see 4.3.
4.1 ATEX certificate
Notified Body Intertek Testing and Certification Ltd
have issued the BA478C with an EC-Type
Examination Certificate number ITS09ATEX26156X.
This states that the transmitter is intrinsically safe and
complies with requirements for Group II, Category 1G
Ex ia IIC T5 equipment. The transmitter bears the
community mark and subject to local codes of
practice may be installed in any of the European
Economic Area (EEA) member countries. ATEX
certificates are also acceptable for installations in
Switzerland.
This instruction manual describes ATEX installations
conforming with EN 60079-14 Electrical Installations
in Hazardous Areas. When designing systems for
installation outside the UK the local Code of Practice
should be consulted.
4.2 Zones, gas groups and T rating
The BA478C has been certified as Group II Category
1G Ex ia IIC T5 apparatus. When connected to a
suitable certified system the BA478C may be
installed in:
Zone 0 explosive gas air mixture
continuously present.
Note: Special conditions apply
see section 4.3
Zone 1 explosive gas air mixture
likely to occur in normal
operation.
Zone 2 explosive gas air mixture not likely
to occur, and if it does will only
exist for a short time.
Be used with gases in groups:
Group A propane
Group B ethylene
Group C hydrogen
Having a temperature classification of:
T1 450oC
T2 300oC
T3 200oC
T4 135oC
T5 100oC
At an ambient temperature between –40 and +70ºC.
This allows the BA478C to be installed in all Zones
and to be used with most common industrial gases.
4.3 Special conditions for Zone 0 installations
The BA478C ATEX certificate has an ‘X’ suffix which
indicates that the transmitter is subject to special
conditions for safe use, which are:
WARNING
The BA478C Indicating Temperature
Transmitter when installed in a Zone 0
potentially explosive atmosphere shall be
installed such that even in the event of
rare incidents, an ignition source due to
impact or friction between the aluminium
enclosure at the rear of the instrument
mounting panel and iron/steel is
excluded.
These special conditions only apply in the very
unlikely event that the transmitter is installed in a
Zone 0 hazardous area. The special conditions
result from the aluminium enclosure and mean that
when installed in a Zone 0 hazardous area, the rear
of the instrument, which will be behind the instrument
mounting panel, should be protected from impact.
4.4 Certification label information
The certification information label is fitted in a recess
on the top outer surface of the enclosure. It shows
details of the ATEX certification, BEKA associates
name and location plus the year of manufacture.
IECEx certification information is also included. The
label on some versions of the transmitter will also
show non-European certification information.
The instruments serial number is shown on the rear
panel adjacent to the terminals.

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4.5 Input terminals 1, 2, 3 and 4
The transmitter’s input terminals may be connected
to any floating or earthed sensor complying with the
requirements for simple apparatus. i.e. a sensor that
generates less than 1.5V; 100mA or 25mW, such as
a thermocouple, resistance thermometer or a
potentiometer.
The transmitter input may also be connected directly
to a voltage source that does not comply with the
requirements for simple apparatus, providing safety is
assessed using the entity concept.
The safety parameters for terminals 1, 2, 3 & 4 are:
Uo = 6.0V
Io = 30.3mA
Po = 46mW
Ui = 6.0V
Ii = 100mA
Pi = 0.194W
Co = 23.8µF
Lo = 3mH
4.6 4/20mA output - terminals 5 & 6
The BA478C Indicating Temperature Transmitter is
loop powered via these terminals which have the
following input safety parameters:
Ui = 28V
Ii = 200mA
Pi = 0.85W
When installed in a hazardous area the transmitter
must be powered via an ATEX certified Zener barrier
or galvanic isolator with output safety parameters
equal to or less than the above.
The equivalent internal capacitance and inductance
at terminals 5 & 6 is:
Ci = 46.5nF
Li = 0.01mH
5. ELECTRICAL SYSTEM DESIGN
The BA478C is a smart HARTenabled loop
powered 4/20mA Indicating Temperature Transmitter.
Intrinsic safety certification allows the instrument and
sensor to be installed in any gas hazardous area
providing that the transmitter is powered via a
certified Zener barrier or galvanic isolator.
For installation in poorly illuminated areas the
BA478C is available with an optional factory fitted
display backlight. No additional wiring of power
supply is required, but the minimum operating voltage
of the transmitter is increased as shown below.
without backlight 9.0 to 28V
with backlight 15.5 to 28V
When the transmitter is fitted with an optional display
backlight the increased minimum operating voltage
usually precludes the use of Zener barriers.
5.1 Use with Zener barriers
There are three requirements when designing a
BA478C loop using Zener barrier(s):
1. The intrinsic safety output parameters of the
Zener barrier must be equal to or less than:
Uo = 28V
Io = 200mA
Po = 0.85W
2. The voltage between terminal 5 & 6 of the
BA478C must be between 9 & 28V.
Note: Zener barriers are not normally able to
power a BA478C transmitter fitted with an
optional display backlight which requires a
minimum operating voltage of 15.5V between
terminals 5 & 6.
3. The maximum supply voltage must not
exceed the maximum working voltage of the
Zener barrier(s).
Fig 2 illustrates the simplest and least expensive
configuration in which a BA478C is powered from an
isolated (floating) power supply. Only one barrier is
required, as the other wire is earthed at the barrier
busbar.

6
Fig 2 BA478C powered from floating supply
If a common power supply is used to operate multiple
loops, the negative side of the supply is normally
earthed. To also allow the negative side of the
4/20mA load to be earthed it is necessary to have a
Zener barrier in each of the two wires entering the
hazardous area as shown in Fig 3.
Fig 3 BA478C powered from a common supply
When designing a transmitter loop it is necessary to
establish that the sum of the voltage drops caused by
the transmitter, Zener barriers, the load and the cable
resistance is less than the minimum supply voltage.
For the transmitter loop shown in Fig.3
Minimum operating voltage of BA478C 9.0V
without optional backlight.
Maximum voltage drop caused by 28V 6.8V
93mA Zener barrier.
(340x 20mA)
Maximum voltage drop caused by 1.6V
diode return Zener barrier.
Maximum voltage drop caused by 5.0V
250load.
(250x 20mA)
Maximum voltage drop caused by 0.2V
cable resistance.
(10x 20mA)
______
Total maximum voltage drop 22.6V
The power supply voltage must therefore be above
22.6V but below the maximum working voltage of the
28V 93mA barrier which is likely to be about 26.5V.
5.2 Use with Galvanic Isolators
A galvanic isolator can supply a higher voltage than a
Zener barrier to a loop powered transmitter and is
able to power a BA478C transmitter fitted with an
optional display backlight which has a minimum
operating voltage of 15.5V. Although an isolator is
more expensive than a Zener barrier it does not
require a high integrity earth. For small systems
where a high integrity earth is not already available a
galvanic isolator may reduce the overall installation
cost. Fig 4 shows a typical temperature transmitter
loop.
Fig 4 BA478C powered via galvanic isolator

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Any ATEX certified 4/20mA repeater power supply or
transmitter power supply galvanic isolator may be
used. There are three requirements when designing
a BA478C loop incorporating a galvanic isolator:
1. The intrinsic safety output parameters of the
galvanic isolator must be equal to or less
than:
Uo = 28V
Io = 200mA
Po = 0.85W
2. The isolator must supply a minimum output
voltage at 20mA of:
BA478C without backlight 9.0V
BA478C with backlight 15.5V
3. If HARTcommunication is to be used the
galvanic isolator must be suitable for powering
‘smart’ transmitters, i.e. it must be transparent
to HARTsignals.
5.3 Use as a temperature indicator
The BA478C may also be used as just a temperature
indicator by ignoring the instrument’s 4/20mA output
current. The same Zener barriers or galvanic
isolators required for transmitter operation are
required, but the load resistor may be omitted.
6. INSTALLATION
6.1 Location
The BA478C is housed in a robust aluminium
enclosure with a toughened glass window mounted in
a Noryl bezel. The front of the instrument provides
IP66 protection and a gasket seals the joint between
the instrument enclosure and the panel. The
instrument may be installed in any panel providing
the environmental limits shown in the specification
are not exceeded.
Fig 5 shows the overall dimensions of the BA478C
and the panel cut-out. To achieve an IP66 seal
between the instrument enclosure and the panel, the
smaller cut-out must be used and the instrument
secured with four panel mounting clips.
The BA478C liquid crystal display has maximum
contrast when viewed from directly ahead and slightly
below the centre line of the instrument.
Fig 5 BA478C dimensions

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6.2 Installation Procedure
a. Insert the BA478C into the instrument panel
cut-out from the front of the panel with the
sealing gasket positioned as shown in Fig 6.
b. Fix panel mounting clips to opposite sides of
the instrument and tighten. Recommended
tightening torque is 22cNm (1.95lbf in). Do not
over tighten. Four clips are required to
achieve an IP66 seal between the instrument
enclosure and the panel.
c. Connect the panel wiring to the rear terminal
block as shown in Fig 6. To simplify
installation, the terminals are removable so
that panel wiring can be completed before the
instrument is installed.
Fig 6 Installation and terminal connections
6.3 EMC
The BA478C complies with the requirements of the
European EMC Directive 2004/108/EC. For specified
immunity, all wiring should be in screened twisted
pairs with the screens earthed at one point in the safe
area.

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7. CONFIGURATION
The BA478C Indicating Temperature Transmitter
may be configured and calibrated via HARTdigital
communication, or configuration may be performed
using the menu accessed via the front panel push
buttons see Fig 5.
Configuration and calibration via HARTmay be
performed using a portable configurator connected
directly to the BA478C or to the galvanic isolator
powering the transmitter, alternatively proprietary
configuration software operating on a personal
computer may be used. In addition to the
configuration functions available via the transmitter
push buttons, HARTcommunication enables loop
calibration and custom linearisation to be performed.
Details of the HARTcommunication are contained in
the BEKA HARTInterface Guide which may be
downloaded from www.beka.co.uk/manuals
7.1 Configuration menu
Throughout this manual the BA478C push buttons
are identified P E ▼▲and legends displayed by
the transmitter are shown within inverted commas
e.g. ‘CAL’ and ‘dEG’. Section 7.1.2 contains a
summary of each configuration function including a
cross reference to a more detailed description.
The functions contained in the configuration menu
vary depending upon the transmitter input selected,
see Figs 7, 8 & 9.
When the transmitter is being configured, the
transmitter 4/20mA output current is locked at the
value prior to entering the configuration menu.
When the optional alarms are fitted additional
functions are added to the configuration menu which
are described in section 10.3.
7.1.1 Access
Access to the configuration menu is obtained by
operating the Pand Ebuttons simultaneously. If the
transmitter is not protected by an access code the
first parameter 'InPut’ will be displayed. If the
transmitter is protected by an access code, ‘CodE’
will be displayed first. Pressing Pwill allow the four
digit security code to be entered digit by digit using
the or button to adjust the flashing digit and Pto
move control to the next digit. When the correct code
has been entered, pressing Ewill cause the first
parameter ‘InPut’ to be displayed. If an incorrect
code is entered, or no button is pressed for ten
seconds, the transmitter will automatically return to
the operating mode.
If the transmitter displays ‘LoC’ when the Pand E
buttons are operated simultaneously, the transmitter
push buttons have been locked by a HART
command - see the BEKA HARTInterface Guide
which may be downloaded from
www.beka.co.uk/manuals
7.1.2 Summary of functions
The functions that may be configured vary depending
upon the input selected.
Thermocouple and RTD inputs
The BA478C will always display sensor temperature.
Configuration allows:
Digital display units and resolution to be selected.
Bargraph display to represent required part of the
digital displayed range.
4/20mA output current to represent required part
of transmitter input range.
Voltage and resistance inputs
The BA478C can display the voltage or resistance
input in any engineering units.
Configuration allows:
Zero and span of digital display to be adjusted.
Bargraph display to represent required part of the
digital displayed range.
4/20mA output current to represent required part
of the transmitter input range.
Each of the functions in the configuration menu is
summarised below, including a cross-reference to a
more detailed description.
Transmitter Summary
display of function
‘InPut’ Transmitter input
Selects one of the following inputs:
Thermocouple ‘tHC’
3 wire RTD ‘3rtd’
4 wire RTD ‘4rtd’
Differential RTD ‘d_rtd’
Voltage ‘Volt’
3 wire resistance ‘3rES’
4 wire resistance ’4rES’
See section 7.2.1
The content of the configuration menu depends upon
which transmitter input is selected, see following
summary and Figs 7, 8 and 9.

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For Thermocouple Input – see Fig 7
Transmitter Summary
display of function
‘t.tYPE’ Thermocouple type
Selects 1 of 8 common types of
thermocouple.
See section 7.2.2
‘dEG’ Units of digital display
Selects 1 of 4 units of temperature.
See section 7.2.3
‘rESn’ Display resolution
Selects low or high display resolution.
See section 7.2.4
‘CJC’ Cold junction compensation
Turns thermocouple cold junction
compensation on or off.
See section 7.2.5
‘FAuLt’ Sensor fault analogue indication
Selects 1 of 3 under/over range output
currents to indicate that a sensor fault has
been detected. Analogue fault indication
may be disabled.
See section 7.2.6
‘CAL’ Configuration of 4/20mA output
Defines transmitter input at which
transmitter output is 4 & 20mA.
See section 7.2.7
‘bAr’ Configuration of bargraph display
Defines digital display at which bargraph
is zero and full scale.
See section 7.2.8
‘CodE’ Access code for configuration menu
Enters four digit configuration menu
access code. Default code 0000 disables
this function.
See section 7.2.9
For Resistance Thermometer (RTD) Input see Fig 8
Transmitter Summary
display of function
‘r.tYPE’ Resistance thermometer type
Selects Pt100 or Pt1000 sensor
See section 7.2.10
‘dEG’ Units of digital display
Selects 1 of 4 units of temperature.
See section 7.2.3
‘rESn’ Display resolution
Selects low or high display resolution.
See section 7.2.4
Transmitter Summary
display of function
‘FAuLt’ Sensor fault analogue indication
Selects 1 of 3 under/over range output
currents to indicate that a sensor fault has
been detected. Analogue sensor fault
indication may be disabled.
See section 7.2.6
‘CAL’ Configuration of 4/20mA output
Defines transmitter input at which
transmitter output is 4 & 20mA.
See section 7.2.7
‘bAr’ Configuration of bargraph display
Defines digital display at which bargraph
is zero and full scale.
See section 7.2.8
‘CodE’ Access code for configuration menu
Enters four digit configuration menu
access code. Default code 0000 disables
this function.
See section 7.2.9
For Voltage and Resistance Inputs – see Fig 9
Transmitter Summary
display of function
‘dP’ Decimal point position
Defines position of displayed decimal
point.
See section 7.2.11
‘in-Lo’ Lower input and display
Defines lower voltage or resistance input
‘inVAL’ and corresponding digital display
‘diSP’.
See section 7.2.12
‘in-Hi’ Higher input and display
Defines higher voltage or resistance input
‘inVAL’ and corresponding digital display
‘diSP’.
See section 7.2.13
‘CAL’ Configuration of 4/20mA output
Defines the transmitter input at which
transmitter output is 4 & 20mA.
See section 7.2.7
‘bAr’ Configuration of bargraph display
Defines digital display at which bargraph
is zero and full scale.
See section 7.2.8
‘CodE’ Access code for configuration menu
Enters four digit configuration menu
access code. Default code 0000 disables
this function. See section 7.2.9

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7.2 Description of configuration menu
functions
This section contains a detailed description of each
function in the configuration menu. It should be read
in conjunction with Figs 7, 8 & 9.
7.2.1 Transmitter input ‘InPut’
This function enables the BA478C indicating
temperature transmitter to be conditioned to operate
with a thermocouple, 3 or 4 wire resistance
thermometer, voltage or 3 or 4 wire resistance input.
A differential resistance thermometer input may also
be selected. A differential thermocouple input is
achieved by selecting the thermocouple input in this
function and turning the cold junction compensation
off in the CJC function – see 7.2.5.
Sensor Transmitter
display
Thermocouple ‘tHC’
3 wire RTD ‘3rtd’
4 wire RTD ‘4rtd’
Differential RTD ‘d_rtd’
Voltage ‘VoLt’
3 wire resistance ‘3rES’
4 wire resistance ’4rES’
The ‘InPut’ function is the first function displayed
when entering the configuration menu, or it may be
selected from within the menu by operating the or
button. To enter the function press Pwhich will
reveal the existing setting which may be changed
using the or button. When the required input
has been selected press Eto enter the selection and
return to the ‘InPut’ prompt in the configuration menu.
7.2.2 Thermocouple type ‘t.tYPE’
This function enables one of eight common
thermocouples to be selected. The following table
shows the thermocouple types, indicator display and
the operating temperature range.
THC BA478C Temperature
Type Display range oC
B ‘b’ 200 to 1820
E ‘E’ -200 to 1000
J ‘J’ -210 to 1200
K ‘H’ -200 to 1372
N ‘n’ -200 to 1300
R ‘r’ -50 to 1768
S ‘S’ -50 to 1768
T ‘t’ -200 to 400
The ‘t.tYPE’ function may be selected from within the
menu by operating the or button. To enter the
function press Pwhich will reveal the existing setting
which may be changed using the or button.
When the required thermocouple has been selected,
press Eto enter the selection and return to the
‘t.tYPE’ prompt in the configuration menu.
7.2.3 Units of digital display ’dEG’
The transmitter digital display may be in one of four
units of temperature.
Units Transmitter Display
oC oC
oF oF
r r
K H
When oC or oF are selected the units of measurement
are shown at the top left hand corner of the display
when the transmitter is in the operating mode.
The ‘dEG’ function may be selected from within the
menu by operating the or button. To enter the
function press Pwhich will reveal the existing setting
which may be changed using the or button.
When the required units have been selected, press E
to enter the selection and return to the ‘dEG’ prompt
in the configuration menu.
7.2.4 Display resolution ‘rESn’
This function defines the resolution of the transmitter
display but does not affect the resolution of the
4/20mA output current.
Resolution Transmitter Display
Lo 0 0 0 0 0
Hi 0 0 0 0.0
The ‘rESn’ function may be selected from within the
menu by operating the or button. To enter the
function press Pwhich will reveal the existing setting
which may be changed using the or button.
When the required resolution has been selected,
press Eto enter the selection and return to the ‘rESn’
prompt in the configuration menu.
7.2.5 Cold junction compensation ‘CJC’
The temperature of the thermocouple cold junction,
which is the transmitter input terminals, is measured
and added to the thermocouple output so that the
transmitter displays and transmits the hot junction
temperature. If cold junction compensation is not
required e.g. for differential measurements with two
thermocouples, this function allows it to be turned off.
The ‘CJC’ function may be selected from within the
configuration menu by operating the or button.
To enter the function press Pwhich will reveal the
existing setting which may be changed using the 
or button. When set as required, press Eto enter
the selection and return to the ‘CJC’ prompt in the
configuration menu.

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7.2.6 Sensor fault analogue indication ‘FAuLt’
The sensor fault analogue indication function appears
in the menu when the transmitter is configured for a
resistance thermometer or a thermocouple input.
When a fault is detected the transmitter’s 4/20mA
output current is set to the specified under or over
range fault value and the transmitter’s digital display
is under or overranged as shown below. One of
three fault currents may be selected, or the fault
indication may be turned off. Irrespective of how the
function is set the transmitter display will flash when a
sensor fault is detected.
Selected Output Transmitter
fault current current display
‘oFF’ No fault indication Flashes
‘dn3.6’ 3.6mA *Flashes
‘dn3.8’ 3.8mA Flashes
‘uP 21’ 21.0mA Flashes
* Not recommended when HART
communication is used.
The ‘FAuLt’ function may be selected from within the
configuration menu by operating the or button.
To enter the function press Pwhich will reveal the
existing setting which may be changed using the 
or button. When set as required, press Eto enter
the selection and return to the ‘FAuLT’ prompt in the
configuration menu.
The typical detection thresholds and approximate
response times are:
Thermocouple > 5k10 sec
RTD sensor < 5>5001 sec
RTD sense leads > 5010 sec
In the time between a fault developing in an RTD
sense lead or a thermocouple and the fault being
detected, the transmitter output and display may drift
from the last correct measured value.
7.2.7 Configuration of 4/20mA output ‘CAL’
This function defines the relationship between the
transmitter input and the 4/20mA output current.
‘Zero’ defines the transmitter input at which the
output is 4mA and ‘Span’ defines the input at which
the output is 20mA.
This function does not affect the transmitter display
which is fixed for thermocouple and resistance
thermometer inputs and adjusted via the ‘in-Lo and
‘in-Hi’ functions for resistance and voltage inputs.
The ‘CAL’ function may be selected from within the
menu by operating the or button. To enter the
function press Pwhich will display the ‘ZEro’ function
in the sub-menu, pressing Pagain will reveal the
existing transmitter input at which the transmitter
output current is 4mA. Input is shown in units which
depend upon how the transmitter input ‘InPut’ and
display ‘dEG’ have been configured, as shown
below:
Configured Input
transmitter input shown as
Thermocouple oC, oF, K or r
Resistance thermometer oC, oF, K or r
Voltage mV
Resistance Ohms
The input, at which the transmitter output current is
4mA, may be changed using the or button to
adjust the flashing digit and the Pbutton to move
control to the next digit. When the required input has
been selected, press Eto enter the selection and
return to the ‘ZEro’ prompt.
The ‘SPAn’ function, which defines the input at which
the transmitter current output is 20mA, may be
selected from within the sub-menu by operating
either the or button. To enter the function press
Pwhich will reveal the existing transmitter input at
which the transmitter output current is 20mA. Again
the input will be shown in units which depend upon
how the transmitter has been configured.
The input, at which the transmitter output current is
20mA, may be changed using the or button to
adjust the flashing digit and the Pbutton to move
control to the next digit. When the required input has
been selected, press Eto enter the selection and
return to the ‘SPAn’ prompt.
Note: When configured for a voltage input, operating
the Pbutton when the 0.1mV digit is flashing in the
‘Zero’ or ‘SPAn’ sub menus increases the input
resolution to 0.01mV which is indicated by the display
colon being activated. When the required input has
been selected, pressing Eenters the selection and
returns the transmitter to the ‘ZEro’ or ‘SPAn’ prompt
in the sub menu.
If, when configured for a voltage or resistance input
the displayed decimal point has been set to
autorange, it may be necessary to manually position
the decimal point before adjusting ‘ZEro’ or ‘SPAn’.
This can be achieved by repeatedly operating the P
button until the activated decimal point flashes, the
decimal point can then be positioned using either the
or button. Pressing the Pbutton again will
return control to one of the digits.

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7.2.8 Configuration of bargraph display ‘bAr’
This function contains three sub-functions that justify
the bargraph display and define the relationship
between the bargraph and the transmitter digital
display.
Sub-function ‘b.tYPE’ enables the bargraph to be left,
centre or right justified, or to be turned off. Sub-
functions ‘bArLo’ and ‘bArHi’ define the transmitter
digital display at which the bargraph starts and is at
full scale.
The ‘bAr’ function may be selected from within the
configuration menu by operating the or button.
To enter the function press Pwhich will display the
‘b.tYPE’ sub-function, pressing Pagain will reveal the
existing bargraph justification. The or button
will scroll through the four options, when the required
justification is displayed, pressing Ewill enter the
selection and return the display to the ‘b.tYPE’
prompt in the sub-menu from which ‘bArLo’ may be
selected using the or button.
‘bArLo’ defines the transmitter digital display at which
the bargraph starts, to enter the function press P
which will reveal the existing setting. The display
may be changed using the or button to adjust
the flashing digit and the Pbutton to move control to
the next digit. When the required starting display has
been selected, press Eto return to the ‘bArLo’ prompt
in the sub-menu from which the ‘bArHi’ function may
be selected.
‘bArHi’ defines the transmitter digital display at which
the bargraph is full scale, to enter the function press
Pwhich will reveal the existing setting. The display
may be changed using the or button to adjust
the flashing digit and the Pbutton to move control to
the next digit. When the required display has been
selected, press Etwice to return to enter the new
values and return to the ‘bAr’ prompt in the
configuration menu.
Note: If, when configured for a voltage or resistance
input the displayed decimal point has been set to
autorange, it may be necessary to manually position
the decimal point before adjusting ‘bArLo’ or ‘bArHi’.
This can be achieved by repeatedly operating the P
button until the activated decimal point flashes, the
decimal point can then be positioned using either the
or button. Pressing the Pbutton again will
return control to one of the digits.
7.2.9 Access code for configuration menu
‘CodE’
Access to the configuration menu may be protected
by a four digit security code which must be entered to
gain access. New instruments are supplied
configured with the default code 0000 which allows
unrestricted access to the menu.
To enter a new access code select ‘CodE’ in the
configuration menu by operating the or button.
To enter the function press Pwhich will reveal the
current access code with one digit flashing. The code
may be changed using the or button to adjust
the flashing digit and the Pbutton to move control to
the next digit. When the required code has been
selected, press Eto enter the selection and return to
the ‘CodE’ prompt in the configuration menu. The
revised access code will be activated when the
transmitter is returned to the operating mode.
If the access code is lost please contact BEKA
associates.
7.2.10 Resistance thermometer type ‘r.tYPE’
This function configures the BA478C to operate with
a Pt100 or Pt1000 resistance thermometer input.
The ‘r.tYPE’ function may be selected from within the
configuration menu by operating the or button.
To enter the function press Pwhich will reveal the
existing setting which may be changed using the 
or button.
Resistance Transmitter
thermometer display
Pt100 100r
Pt1000 1000r
When the required resistance thermometer has been
selected, press Eto enter the selection and return to
the ‘r.tYPE’ prompt in the configuration menu.
7.2.11 Decimal point position ‘dP’
This function defines the position of the displayed
decimal point when the transmitter is configured for a
voltage or a resistance input.
This function does not appear in the configuration
menu when the transmitter is configured for a
thermocouple or a resistance thermometer input.
The ‘dP’ function may be selected from within the
menu by operating the or button. To enter the
function press Pto reveal the existing position of the
decimal point which may be moved to the required
position, or omitted, by operating the or button.
Autorange, which is selected when all the decimal
points are activated, ensures that the transmitter
numeric display is always shown with maximum
resolution irrespective of the value. When set as
required, press Eto enter the selection and return to
the ‘dP’ prompt in the configuration menu.

14
7.2.12 Lower input & display ‘in-Lo’
This function, which only appears in the menu when
the transmitter is configured for a voltage or
resistance input, defines the transmitter lower input
voltage or resistance ‘inVAL’ and the corresponding
transmitter digital display ‘diSP’.
This function does not affect the transmitter output
current which is defined by the ‘CAL’ function.
The ‘in-Lo’ function may be selected from within the
configuration menu by operating the or button.
To enter the function press Pwhich will display
‘inVAL’ in the sub-menu, pressing Pagain will reveal
the existing transmitter lower input voltage or
resistance. ‘InVAL’ is shown in units which depend
upon how the transmitter input ‘inPut’ has been
configured, as shown below:
Configured ‘inVAL’
transmitter input units resolution
Voltage mV 0.1 or 0.01mV
Resistance 0.1
‘inVAL’ may be adjusted using the or button to
adjust the flashing digit and the Pbutton to move
control to the next digit. When configured for a
voltage input, operating the Pbutton when the 0.1mV
digit is flashing increases the resolution to 0.01mV
which is indicated by the display colon being
activated. When the required input has been
selected, press Eto enter the selection and return to
the ‘inVAL’ prompt in the sub menu.
‘diSP’ which is the transmitter display corresponding
to ‘inVAL’ may be selected from within the sub-menu
by operating either the or button. To enter the
function press Pwhich will reveal the existing lower
transmitter display. The display may be changed
using the and buttons to adjust the flashing digit
and the Pbutton to move control to the next digit.
The position of the displayed decimal point is set by
the dP function – see section 7.2.11. When the
required transmitter display has been selected, press
Etwice to enter the selection and return to the
configuration menu.
Note: When the displayed decimal point has been
set to autorange, it may be necessary to manually
position the decimal point before adjusting ‘inVAL’.
This can be achieved by repeatedly operating the P
button until the activated decimal point flashes, the
decimal point can then be positioned using either the
or button. Pressing the Pbutton again will
return control to one of the digits.
7.2.13 Higher input & display ‘in-Hi’
This function which only appears in the menu when
the transmitter is configured for a voltage or
resistance input, defines the transmitter higher input
voltage or resistance ‘inVAL’ and the corresponding
transmitter digital display ‘diSP’.
This function does not affect the transmitter output
current which is defined by the ‘CAL’ function.
The ‘in-Hi’ function may be selected from within the
configuration menu by operating the or button.
To enter the function press Pwhich will display
‘inVAL’ in the sub-menu, pressing Pagain will reveal
the existing transmitter higher input voltage or
resistance. ‘InVAL’ is shown in units which depend
upon how the transmitter input ‘inPut’ has been
configured, as shown below:
Configured ‘inVAL’
transmitter input units resolution
Voltage mV 0.1 or 0.01mV
Resistance 0.1
‘inVAL’ may be adjusted using the or button to
adjust the flashing digit and the Pbutton to move
control to the next digit. When configured for a
voltage input, operating the Pbutton when the 0.1mV
digit is flashing increases the resolution to 0.01V
which is indicated by the display colon being
activated. When the required input has been
selected, press Eto enter the selection and return to
the ‘inVAL’ prompt in the sub menu.
‘diSP’ which is the transmitter display corresponding
to ‘inVAL’ may be selected from within the sub-menu
by operating either the or button. To enter the
function press Pwhich will reveal the existing higher
transmitter display. The display may be changed
using the or button to adjust the flashing digit
and the Pbutton to move control to the next digit.
The position of the displayed decimal point is set by
the dP function – see section 7.2.11. When the
required transmitter display has been selected, press
Etwice to enter the selection and return to the
configuration menu.
Note: When the displayed decimal point has been
set to autorange, it may be necessary to manually
position the decimal point before adjusting ‘inVAL’.
This can be achieved by repeatedly operating the P
button until the activated decimal point flashes, the
decimal point can then be positioned using either the
or button. Pressing the Pbutton again will
return control to one of the digits.

15

16

17

18
7.3 Default configuration
If the transmitter’s configuration is not specified at the
time of ordering, the instrument will be configured as
follows but can easily be reconfigured on-site.
Function Factory default
Transmitter input ‘InPut’ 3 wire RTD
Sensor type ‘t.tYPE’ Pt100
Units of digital display ‘dEG’ ºC
Display resolution ‘rESn’ Low
Sensor fault ‘FAuLt’ Off
4/20mA output ‘CAL’ 0.0 to 100.0
Bargraph display ‘bAr’ Left hand
justification.
Bargraph starts at
digital display 0.0
and finishes at
digital display
100.0
Access code ‘CodE’ 0000 which
disables this
function.

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8. CONFIGURATION EXAMPLE
In this example a BA478C 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 +250oC. . A left hand
justified bargraph representing 100.0 to 200.0oC 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 5. The BA478C can be supplied
with factory fitted external push buttons if frequent
adjustments are required.
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 BEKA
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 8 and section 7.2.1
New BA478C 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 Pand Esimultaneously which
will cause the first prompt ‘InPut’ to be
displayed. Press Pto 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 Eto enter the selection
and return to the ‘InPut’ prompt in the
configuration menu.
Step 2 Select resistance thermometer type
See: Fig 8 and section 7.2.10
Using the or button select the
‘r,tYPE’ prompt from the configuration
menu and press Pto 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 Ebutton that
will return the display to the ‘r.tYPE’
prompt in the configuration menu.
Step 3 Select units of digital display
See: Fig 8 and section 7.2.3
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 Eto enter the selection and return
the transmitter display to the ‘dEG’
prompt in the configuration menu.
Step 4 Select display resolution
See: Fig 8 and section 7.2.4
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 Eto enter this selection
and return the display to the ‘rESn’
prompt in the configuration menu.
Step 5 Sensor fault detection
See: Fig 8 and section 7.2.6
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 Ewhich will also return the
transmitter display to the ‘FAuLt’ prompt
in the configuration menu.
Step 6 Configuration of 4/20mA output
See: Fig 8 and section 7.2.7
The BA478C transmitter input at which
the transmitter output current is 4mA
and 20mA is defined by the ‘CAL’
function which contains two sub-
functions.
Using the or button select ‘CAL’
from the configuration menu and press P
which will show the ‘ZEro’ sub-function
prompt. Press Pagain to enter this sub-
function, which will reveal the existing
input at which the transmitter output
current is 4mA. Adjust the display to
the required –0010.0 using the or 
button to adjust the flashing digit and the
Pbutton to move control to the next
digit. A negative display is achieved by
scrolling the most significant digit below
zero using the button. When set

20
press Eto enter the new value and
return to the ‘ZEro’ sub-function prompt
from which the ‘SPAn’ sub-function,
which defines the display at which the
output is 20mA, may be selected using
the or button. Press Pto enter this
sub-function, which will reveal the
existing input at which the transmitter
output current is 20mA. Adjust the
display to 0250.0 using the or 
button to adjust the flashing digit and the
Pbutton to move control to the next
digit.
Finally press Etwice, first to enter the
selection and return to the ‘SPAn’ sub-
function prompt, and again to return to
the ‘CAL’ function prompt in the
configuration menu.
Step 7 Configuration of bargraph display
See: Fig 8 and section 7.2.8
This function contains three sub-
functions that justify the bargraph
display and define the transmitter digital
display at which the bargraph starts and
finishes.
Using the or button select ‘bAr’
from the configuration menu and press P
which will show the ‘b.tYPE’ sub-function
prompt. Press Pagain to enter this sub-
function, which will reveal the existing
bargraph justification. Using the or 
button scroll through the options and
select ‘LEFt’ which will start the
bargraph on the left hand side of the
display. Press Eto enter the selection
and return to the ‘b.tYPE’ sub-function
prompt from which, using the or 
button, the ‘bArLo’ sub-function may be
selected. Press Pto enter the ‘bArLo’
sub-function which will reveal the
existing digital display at which the
bargraph starts. Set the display to
0100.0 using the or button to
adjust the flashing digit and the Pbutton
to move control to the next digit. When
set, press Eto enter the new value and
return to the ‘bArLo’ sub-function prompt
from which the ‘bArHi’ sub-function may
be selected. Press Pto enter the
‘bArHi’ sub-function which will reveal the
existing digital display at which the
bargraph finishes. Set the display to
0200.0 using the or button to
adjust the flashing digit and the Pbutton
to move control to the next digit.
Finally press Etwice, first to enter the
selection and return to the ‘bArHi’ sub-
function prompt, and again to return to
the ‘bAr’ function prompt in the
configuration menu.
Step 8 Enter the configuration
menu access code.
See Fig 8 and section 7.2.9
This function defines the four digit code
that must be entered to obtain access to
the BA478C transmitter’s configuration
menu.
Using the or button select the
‘CodE’ prompt from the configuration
menu and press Pwhich, for a new
instrument, will show the default code
‘0000’ with the first digit flashing. Using
the or button to adjust the flashing
digit and the Pbutton to transfer control
to the next digit, set the display to 1209.
Press Etwice to enter the new access
code and return the BA478C to the
display mode via the ‘CodE prompt.
This completes the instrument
configuration. The BA478C transmitter
will now function as specified at the
beginning of this example. Access to
the configuration is protected by code
1209 which must be entered each time a
change is made.