- #1
idvdi
- 1
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i am working on my project but i do not have much practical experience on connecting the circuit, hence asking for help here.
ok here's my problem.
i have a temperature sensor LM35 which its Vout = 10mV/˚C.
the output of the temperature sensor has to be connected to PLC input.
when the output is higher than 270mV (27˚C), the nothing will happen.
when the output is equal or lower than 270mV (27˚C), PLC input will receive 5V constant voltage.
i have done research with op-amp (comparator) with negative feedback and successfully make it into a positive voltage when the temperature is lower than 27˚C.
anyhow, the voltage is in a wide range from 5v to 50v, depends on the temperature difference.
i have also done research with voltage regulator but most of them do not receive such a wide range of input.
when the temperature is lower than 27˚C, how can i make it constantly 5V to the PLC input?
ok here's my problem.
i have a temperature sensor LM35 which its Vout = 10mV/˚C.
the output of the temperature sensor has to be connected to PLC input.
when the output is higher than 270mV (27˚C), the nothing will happen.
when the output is equal or lower than 270mV (27˚C), PLC input will receive 5V constant voltage.
i have done research with op-amp (comparator) with negative feedback and successfully make it into a positive voltage when the temperature is lower than 27˚C.
anyhow, the voltage is in a wide range from 5v to 50v, depends on the temperature difference.
i have also done research with voltage regulator but most of them do not receive such a wide range of input.
when the temperature is lower than 27˚C, how can i make it constantly 5V to the PLC input?