Answer / carl_ellis

Any 2 wire, loop powered 4-20mA transmitter that puts out
30mA is broken. The only transmitter that puts out 30mA is
a legacy 10-50mA transmitter from 20-30 years ago.

While the upper end of the 4-20mA signal range is 20.0mA,
most 2 wire, loop powered transmitters allow for some slight
signal over-range, typically 20.5mA.

NAMUR standards use 21.0 mA to signal a fault or failure
mode. Other vendors use other values, 20.8mA, 21.2mA or
some value in the range of 21mA. But no vendor uses 30mA
as a fault mode.

The transmitter is broken or dysfunctional.

Carl Ellis
Measure First

Paper Details: company -- Hindustan Copper Limited post -- GET 2008 Date -- 03.08.2008 Dept.-- Electronics?Instrumentation Aptitude -- 70 Technical-- 80 Total Time -- 2hr 30min I have listed the question I could able to remember 1. BCD equivalent of 43 2. value of K for stability of a system from a given equation 3. transformer connection for darlington connection 4. damping of balastic galvanometer 5. advantage of chart-pen recorder over CRo 6. CRO - how to change bandwidth 7. questions on CRO construction 8. reverse saturation current of si diode 9. advantage of wire wound resistance over carbon resistance 10. core material for a small coil 11. max fanout-- TTL/ECL/CMOS/MOS 12. component of resistance of monolithic IC 13. functions of capacitors in multivibrators 14. to change a sawtooth signal into a square wave we use-- schmit trigger/ schottkey diode/ zener diode 15. relation b/w á & â in transistor ckt 16. function of SiO2 layer in fabrication 17. 3 questions on ODD MAN OUT

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