What does “Downscale burnout” mean?
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The derating level for burnout required of the temperature transmitter is set so low that an alarm will sound when the transmitter fails. I would like to ask fellow sailors: how should this sentence be translated?
The meanings of Upscale and Downscale Burnout: The thermocouple burn-out function is primarily used in temperature control systems that have a thermocouple as an input source. When the thermocouple fails, the controller loses its input signal; this results in the measured temperature becoming very low. In response, the controller tries to increase the heat supply, which can cause the process to overheat, such as in the case of a furnace. To prevent such overheating, transmitters are equipped with a burn-out function. The simple circuit associated with this function generates a fake signal with a high electromotive force when there is a break in the circuit of the thermocouple or its connection wires. This causes the transmitter’s output to be higher than 100% (or lower than 0%, if that is selected). The controller then responds to this signal above 100% by reducing the output level. Temperature control systems with this burn-out function prevent overheating in cases where the thermocouple fails. Thermocouple transmitters offer three options for this burn-out function: 1. The output signal becomes higher than 100%. (= Upscale burn-out) 2. The output becomes lower than 0%. (= Downscale burn-out) 3. No burn-out function
The degree of degradation required for the temperature transmitter to trigger a low-level alarm is set very low, so an alarm is emitted when the transmitter fails. The transmitter needs to be damaged to a minimal extent before such a low-level alarm is triggered.
This post was last edited by vzb_2000 on 2016-1-19 at 15:19. The transmitter should have a low-limit fault output function, so that a low alarm is triggered in case of a transmitter failure.
Thank you, thank you; I just don’t understand the part you explained. I’m currently asking the person in charge of the instruments about this function; what does EMF stand for here? Is it electromotive force?
Yes. EMF = “electromotive force“; the electromotive force generated by thermocouples when used for temperature measurement“