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Transmitter Burnout
Can anyone explain what is meant by Transmitter burnout and Burnout direction setting?

Can anyone explain what is meant by Transmitter burnout and Burnout direction setting?

By Sadiq Syed on 10 June, 2007 - 10:24 am

Transmitter burnout means failure due to some unknown reasons. Burnout direction means what would you like, your transmitter to output when it fails show maximum value (i.e burnout in high direction) or make it show minimum value (i.e burnout in low direction ). The type of burnout direction would depend upon the different factors such as quality of product, safety of personel, equipment protection. Hope that helps you.

Syed

It sounds like FAILSAFE (High/low). Is it the same?

Failsafe is a terminology used for valves and its with reference to position. Open or close.

But yes more or less it is the same thing.

By Swarna Balaji on 3 April, 2018 - 3:31 am

If any transmitter fails, it is necessary to protect the process. During ordering of the transmitter, we have to decide whether burn out direction to be high side or low side. Example: If any pump is having trip on high temperature of process fluid, then we have to select burn out direction as high for that particular temperature transmitter (if it fails). That means, control system understands that transmitter's value is high, then it trips the pump. This is FAIL SAFE MODE.

>Can anyone explain what is meant by Transmitter burnout and
>Burnout direction setting?

On a somewhat related topic I remember a Lube Oil tank with a heater to bring the oil up to temperature. The heater was controlled by a PLC reading a temperature transmitter in the tank.

During commisioning someone turned the Instrument power panel off overnight. The temperature transmitter in the tank dropped to zero mA so of course the PLC turned the heater ON, the oil was nearly boiling by the morning.

After that I always turned the heaters Off above setpoint or below ambient.
It's not quite the same as burnout protection which would have the transmitter fail high 20-22 mA, but just as important to have the logic look after unexpected events.

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Burnout direction refers to how a transmitter indicates that there is a problem over an analog control loop. For instance, let's say your temperature transmitter is set to high burnout. It detects an out of range value from the RTD it's using, so it transmits 21 mA. The PLC AI sees this and understands it is outside of the acceptable 4-20 mA range, so it can trigger an alarm for a failed sensor/transmitter. Alternatively, it might transmit 3.6 mA if set to low burnout to indicate the same thing.