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ACCESSORIES

10.  IDENTIFICATION AND MOUNTING

10.1  Engraved scale and tag plates

All BA374NC indicators are fitted with blank
stainless steel scale and tag plates above and
below the display.   These can easily be removed
for engraving, or if requested they can be supplied
engraved with any units of measurement and tag
information.  Each plate can accommodate:

       1 row of 9 alphanumeric characters 10mm high

   or 1 row of 13 alphanumeric characters 7mm high

   or 2 rows of 18 alphanumeric characters 5mm high

10.2  Pipe mounting kits 

Two pipe mounting kits are available for securing
the BA374NC to a horizontal or vertical pipe.

BA392

Stainless steel bracket secured by two
worm drive hose clips.  Will clamp to
any vertical or horizontal pipe with
outside diameter between 60 and
80mm.

BA393

Heavy duty stainless steel bracket
secured by a single 'V' bolt.  Will clamp
to any vertical or horizontal pipe with an
outside diameter between 40 and
80mm.

10.3  Panel mounting kit

The BA394 panel mounting kit will secure the
BA374NC indicator into a panel aperture.  All parts
are stainless steel and the kit contains a trim-plate
to conceal the edge of the panel aperture.

11.0  ALARMS

The BA374NC can be supplied with two solid state
single pole alarm outputs.  Each output may be
programmed as a high or low alarm with a
normally open or a normally closed output.  Fig 8
illustrates the conditions available and shows
which are fail safe, i.e. output is in the alarm
condition (open) when the transmitter is not
powered.   When an alarm is activated the
indicator display alternates between the measured
value and an alarm identification.

WARNING!

These alarm outputs should not be
used for critical safety applications
such as an emergency shut-down
system

Fig 8  Alarm outputs

Programmable functions for each alarm include
adjustable hysteresis, alarm delay and alarm
accept.

11.1.1  Solid state output 

Each alarm has a galvanically isolated single pole
solid state switch output as shown in Fig 9.   The
output is polarised and current will only flow in one
direction.

Fig 9 Equivalent circuit of each alarm output

11.1.2  Type n certification

Each of the two alarms is a galvanically isolated
single pole solid state switch which has been
certified as a separate EEx nL Group II, Category
3G circuit.

The input safety parameters for each switch are:

Ui

30V

Ii

100mA

Pi

0.2W

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Summary of Contents for BA374NC

Page 1: ...BA374NC Type nL certified field mounting indicating temperature transmitter Issue 5 3rd December 2003...

Page 2: ...brating the internal references 6 8 1 Conditioning internal references 6 8 2 Voltage input reference 6 8 3 3 wire RTD reference 6 8 4 4 wire RTD reference 6 8 5 Output current reference 7 Trim Menu 7...

Page 3: ...tion 6 you will find information on setting up for Section 6 3 Thermocouple input Section 6 4 Resistance thermometer input Section 6 5 Voltage input A word of warning Section 6 8 explains how you can...

Page 4: ...4...

Page 5: ...mperature measurement applies linearisation using look up tables stored in permanent memory The resulting temperature is shown on the internal display The 4 20mA output current is proportional to the...

Page 6: ...components which may generate a spark in normal operation e g switches and switches and potentiometers These approvals confirm that the BA374NC is safe in normal operation and may be installed in Zone...

Page 7: ...res are surface mounting but may be pipe or panel mounted using the accessory kits described in section 10 Fig 3 BA374NC installation procedure To simplify installation the enclosure may be installed...

Page 8: ...accuracies Each function in the Programme Menu is summa rised in section 6 1 and includes a cross reference to more detailed information in the following sections Although this simple menu driven syst...

Page 9: ...9...

Page 10: ...10...

Page 11: ...can be reached by scrolling through the functions using the Up and Down push buttons as shown in Figs 5A and 5B When returning to the display mode following changes to any parameters the transmitter w...

Page 12: ...See section 6 2 1 For Thermocouple Inputs tYPE Sensor type Selects the type of thermocouple input See section 6 3 1 dEg Units of display Sets display to o C or o F See section 6 3 2 rESn Display reso...

Page 13: ...pressing P will reveal a sub menu from which for thermocouple and resistance thermometer inputs the type of sensor may be selected and associated parameters programmed 6 3 For thermocouple inputs 6 3...

Page 14: ...eit To check or change the display units select dEg from the sub menu and press P to reveal the current setting The setting may be changed by pressing the Up or Down button When the required unit is d...

Page 15: ...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 an...

Page 16: ...ined in a protected sub menu to minimise the possibility of accidental adjustment Select Cond from the menu and press P The transmitter will display 0000 Using the Up and Down buttons and the P button...

Page 17: ...Pressing P will change the display to 020A and the transmitter output current to approximately 20mA The transmitter output current shown on the external current measuring instrument should be adjusted...

Page 18: ...re of the primary element operate the Up or Down buttons until the transmitter display is correct Immediately the Up or Down button is operated the annunciator in the top left hand corner of the displ...

Page 19: ...uple With tHC displayed press P to enter the thermocouple sub menu The first parameter tYPE will be displayed pressing P again will give access to the seven different types of thermocouple Select J us...

Page 20: ...be less accurate With the transmitter displaying the ZEro prompt and the correct input connected to the transmitter push P which will cause the transmitter to display the thermocouple temperature Adju...

Page 21: ...osure Before replacing the instrument front cover ensure that the sealing gasket is undamaged and is free from dirt and foreign bodies If a BA374NC fails after it has been functioning correctly the pr...

Page 22: ...eel and the kit contains a trim plate to conceal the edge of the panel aperture 11 0 ALARMS The BA374NC can be supplied with two solid state single pole alarm outputs Each output may be programmed as...

Page 23: ...gain only the functions on alarm 1 are listed but alarm 2 has identical facilities 11 2 Summary of programmable alarm functions Display Summary of function EnbL Alarm enable Enables or disables the al...

Page 24: ...24 Fig 11 Programme structure for optional alarms...

Page 25: ...rm output status select no nc from the alarm sub menu and press P reveal the current setting The function can be changed by pressing the Up or Down button followed by the E button to return the no nc...

Page 26: ...cSP prompt in the Programme Menu Code 0000 will disable the security code allowing direct access to the setpoints by pressing the P and Up buttons simultaneously New instruments are supplied with this...

Page 27: ...input safety parameters are Ui 30V dc Ii 100mA Pi 1 3W This allows the backlight to be powered from a safe area 18 to 30V dc supply as shown in Fig 13 Providing the supply voltage in normal operation...

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