Transmitter/diaphragm seal systems should be considered when:
• The process temperature is outside of the normal operating ranges of the transmitter and cannot be brought into those limits with impulse piping.
• The process is corrosive and would require frequent transmitter replacement or specific exotic materials of construction.
• The process contains suspended solids or is viscous and may plug the impulse piping.
• The application requires the use of sanitary connections.
• There is a need for easier cleaning of the process from the connections to avoid contamination between batches.
• There is a need to replace wet/ dry legs to reduce maintenance on applications where the reference leg is not stable or often needs to be refilled/drained.
• There is a need to make density or interface measurements.
• The process medium may freeze or solidify in the transmitter or impulse piping.