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1.

DESCRIPTION

These field mounting, intrinsically safe digital
indicators display the current flowing in a 4/20mA
loop in engineering units. They are loop powered
but only introduce a 1.2V drop, which allows them
to be installed into almost any 4/20mA current
loop.

No additional power supply or battery is

required.

The four models are electrically similar, but have
different size displays and enclosure materials.

Model

        Display

BA304G

4 digits 34mm high in
GRP enclosure.

BA304G-SS

4 digits 34mm high in
stainless steel enclosure.

BA324G

5 digits 29mm high and
31 segment bargraph
in GRP enclosure.

BA324G-SS

5 digits 29mm high and
31 segment bargraph in
stainless steel enclosure.

This

instruction

manual

supplements

the

instruction sheet supplied with each instrument.

The main application for all models is to display a
measured variable or control signal in a hazardous
process area. The zero and span of the display
are independently adjustable so that the indicator
can be calibrated to display any variable
represented

by

the

4/20mA

current,

e.g.

temperature, flow, pressure or level.

All models have been certified intrinsically safe for
use in gas and dust hazardous areas by Notified
Body Intertek Testing and Certification Ltd and
comply

with the European ATEX Directive

2014/34/EU. The EC-Type Examination certificate
specifies that under fault conditions the output
voltage, current and power at the 4/20mA input
terminals will not exceed those specified for

simple

apparatus

in Clause 5.7 of EN 60079-11, which

simplifies installation and documentation.

For international applications all models have
IECEx

certification

which

is

described

in

Appendix 2.

For applications in the USA and Canada all models
have ETL and cETL certification which is described
in Appendix 3.

2.

OPERATION

Fig 1 shows a simplified block diagram of all
models. The 4/20mA input current flows through
resistor R1 and forward biased diode D1. The
voltage developed across D1, which is relatively
constant, is multiplied by a switch mode power
supply and used to power the instrument. The
voltage developed across R1, which is proportional
to the 4/20mA input current, provides the input
signal for the analogue to digital converter.

Each time a 4/20mA current is applied to the
instrument, initialisation is performed during which
all segments of the display are activated, after five
seconds the instrument displays the input current
using the calibration information stored in the
instrument memory. If the loop current is too low
to power the instrument the indicator will display
the error message 

LPLo

.

Fig 1  Indicator block diagram

Summary of Contents for BA304G

Page 1: ...Issue 5 19th September 2018 BA304G BA304G SS BA324G BA324G SS intrinsically safe loop powered field mounting indicators Issue 5...

Page 2: ...to a new indicator 7 3 Under and over range 7 4 Lineariser default configuration 8 Maintenance 8 1 Fault finding during commissioning 8 2 Fault finding after commissioning 8 3 Servicing 8 4 Routine ma...

Page 3: ...sting and Certification Ltd and comply with the European ATEX Directive 2014 34 EU The EC Type Examination certificate specifies that under fault conditions the output voltage current and power at the...

Page 4: ...d Body Intertek Testing and Certification Ltd have issued all the models with a common EC Type Examination Certificate number ITS11ATEX27253X This confirms compliance with harmonised European standard...

Page 5: ...face of the instrument assembly It shows the ATEX and IECEx certification information and BEKA associates name and location Non European certification information may also be shown The instrument seri...

Page 6: ...sufficient to drive the indicator plus the interface When a high integrity earth connection is already available a Zener barrier is usually the least expensive option If an earth connection is not ava...

Page 7: ...ing cable screens If field wiring is to be terminated prior to the installation of the indicator assembly the GRP models BA304G and BA324G can be supplied with an optional back box terminal assembly w...

Page 8: ...for joining cable screens 5 6 Units of measurement and tag marking on scale card The indicator s units of measurement and tag information are shown on a scale card which slides into the indicator New...

Page 9: ...e card carefully insert it into the slot on the right hand side of the input terminals as shown in Fig 6b Force should be applied evenly to both sides of the scale card to prevent it twisting The card...

Page 10: ...A324G BA304G SS BA324G SS Access code CodE 0000 0000 Function FunC Linear Linear Display at 4mA 2ero 0 0 0 00 Display at 20mA 5PAn 100 0 100 00 Resolution rE5n 1 digit 1 digit Bargraph start BarLo 0 0...

Page 11: ...11...

Page 12: ...Lin 16 segment adjustable lineariser To reveal the indicator s existing function select FunC from the configuration menu and press If the function is set as required press to return to the menu or pre...

Page 13: ...e two currents is greater than 4mA If these conditions are not complied with the indicator displays FaiL and aborts the calibration c If the zero current is greater than the span current the instrumen...

Page 14: ...on and oFF When set as required press to return to the tARE prompt in the configuration menu 6 10 Security code CodE Access to the instrument configuration menu may be protected by a four digit securi...

Page 15: ...ws direct calibration of the lineariser with an external current source and is the preferred method when traceability is required If the exact system non linearity is unknown this method also allows d...

Page 16: ...16...

Page 17: ...g break point 7 1 1 Example Adding break points to a new indicator When adding break points to a new indicator or to a lineariser following resetting to the factory defaults using the LtAb function de...

Page 18: ...pressing the button The corresponding indicator display at each of the break points can now be defined using the di5P sub function Using the and buttons select the di5P sub function and press which wi...

Page 19: ...ertificate is available If an indicator fails after it has been functioning correctly follow the procedure shown in section 8 1 If this does not reveal the cause of the fault it is recommended that th...

Page 20: ...ered the backlight produces green background illumination enabling the display to be read at night or in poor lighting conditions No additional power supply intrinsic safety interface or field wiring...

Page 21: ...rgency shut down system Both models can be supplied with factory fitted dual solid state single pole alarm outputs Each alarm output may be independently configured as a high or low alarm with a norma...

Page 22: ...simple apparatus This simplifies system documentation and allows the alarm output terminals 8 9 and 10 11 to be connected to almost any intrinsically safe circuit protected by a Zener barrier or galv...

Page 23: ...23...

Page 24: ...tpoint The alarm is activated when the indicator display equals the setpoint See section 9 3 5 Hi Lo Alarm function Defines the alarm function as High or Low See section 9 3 6 no nC Normally open or n...

Page 25: ...for fail safe operation both alarm outputs should be conditioned to be open in the alarm condition nC To check or change the alarm output status select no nC from the alarm configuration menu and pre...

Page 26: ...t having access to the indicator configuration menu Protection against accidental adjustment of the setpoints when the indicator is in the display mode is provided by a separate security code This dir...

Page 27: ...tpoint plus the displayed value to be represented or a low and a high setpoint plus the displayed value to be represented by the bargraph as shown in Fig 18 Fig 18 Displayed value and setpoints on bar...

Page 28: ...d into a panel aperture The kit provides an IP66 seal between the indicator and the instrument panel it is therefore suitable for mounting a stainless steel indicator in a sealed panel enclosure 9 6 B...

Page 29: ...nly persist for a short period Be used with dust in subdivisions IIIA combustible flyings IIIB non conductive dust IIIC conductive dust Having a Minimum Ignition Temperature of Dust cloud 120 C Dust l...

Page 30: ...cifies the following certification codes Ex ia IIC T5 Ga Ex ia IIIC T80 C Da IP66 Ta 40 C to 70 C The specified IECEx gas and dust intrinsic safety parameters are identical to the ATEX safety paramete...

Page 31: ...70 C CL II Div 1 Groups E F G 40 C Ta 60 C CL III Div 1 40 C Ta 60 C USA Zone classification CL I Zone 0 AEx ia IIC T5 Ga 40 C Ta 70 C Zone 20 AEx ia IIIC T80 C Da 40 C Ta 60 C Canada Zone classificat...

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