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Issue:  5

11

th

 November 2009

BA304NC

Type nL

Loop-powered

3½ digit field

mounting indicator

issue 5

Содержание BA304NC

Страница 1: ...Issue 5 11th November 2009 BA304NC Type nL Loop powered 3 digit field mounting indicator issue 5...

Страница 2: ...al point 6 4 Reverse action 6 5 Calibration example 6 6 Over and under range 7 Maintenance 7 1 Fault finding during commissioning 7 2 Fault finding after commissioning 7 3 Servicing 7 4 Routine mainte...

Страница 3: ...ly constant is multiplied by a switch mode power supply and used to power the analogue to digital converter and liquid crystal display The voltage developed across R1 which is proportional to the 4 20...

Страница 4: ...erminals 1 and 3 may be safely connected in series with any 4 20mA loop providing that in normal operation the input current to the indicator does not exceed 40mA 3 4 Certification Label Information T...

Страница 5: ...5V 4 2 Remote indication A BA304NC indicator may be driven from a 4 20mA safe area signal to provide a remote indication within a Zone 2 hazardous area Fig 3 shows a typical application in which the o...

Страница 6: ...cable entries and install Ex e or Ex n certified glands conduit fittings or blanking plugs e Connect the field wiring to the terminals as shown in Fig 5 f Replace the indicator assembly and evenly ti...

Страница 7: ...e between Elevation 0 and 1000 Suppression 0 and 1000 Zero link Position Display with 4mA input adjustable between 0 to 500 0 and 500 500 to 1000 500 to 1000 6 2 Span adjustment Span is defined as the...

Страница 8: ...ed in front of the least significant digit therefore the decimal point link should be placed in the 00 0 position Step 5 With 4 000mA input adjust the zero potentiometer until the indicator displays 2...

Страница 9: ...Fault finding after commissioning CAUTION ENSURE PLANT SAFETY BEFORE STARTING MAINTENANCE Live maintenance should only be performed when there is no risk of a flammable atmosphere being present and d...

Страница 10: ...all ATEX certified indicator assemblies carry the legend ATEX If after replacement of the indicator assembly the instrument still does not function it is likely that the fault is within the protectio...

Страница 11: ...ntiometer should not be used to set the display to zero with a 4mA input Zero suppression or elevation may not be used i e 4mA must correspond to zero flow For reference the following table shows the...

Страница 12: ...s less than 30V dc in normal operation the backlight safety components will ensure that the maximum input current and power are within the safety limits Fig 8 Separately powered backlight Reducing the...

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