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Entry type: FAQ Entry ID: 42626355, Entry date: 04/29/2010

Operating principle of the two-wire system

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How is the two-wire circuit designed to transmit values measured by temperature sensors?







Two-wire system for transmitting measured values
    The two-wire circuit is used for short line sections and when slight temperature fluctuations are present in the vicinity of the measuring leads. The measuring current is supplied via two supply cables. Any changes in the resistance of the measuring leads (e.g. as a result of changes in the ambient temperature) are immediately recorded as measuring errors.



The temperature sensors for electrical machines are routed as standard as far as the auxiliary terminal box of the machine in a two-wire system.




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