Yokogawa transmitter mode issue

S1 and S2 on the nameplate of the Yokogawa intelligent transmitter represent different measurement modes: S1 mode is the single-sided measurement mode. In this mode, the transmitter has only one pressure interface (usually labeled H or P), which is used to connect to the pressure source being measured. This mode is simple and easy to use, suitable for measuring gauge pressure, absolute pressure, and vacuum level. For example, in ordinary pipeline pressure measurement, if only the value of the pressure inside the pipeline relative to atmospheric pressure is needed, a transmitter in S1 mode can be used. S2 mode: Also known as relative pressure measurement mode or differential pressure mode. Transmitters of this type have two pressure interfaces (usually labeled H and L), which are connected to the positive and negative sides of the pressure being measured, respectively. It can eliminate the effects of changes in environmental pressure, making it suitable for measuring minor pressure changes and fluctuations, as well as in situations where accurate measurement of pressure differences is required. For example, when measuring the pressure difference across a filter to monitor its degree of clogging, transmitters in S2 mode can perform very well.

This post was last edited by zzhzh on 2025-7-24 at 16:46. It’s not that mysterious actually; S1 and S2 differ only in color, with S1 being the older gray-green version； S2 is bright green