Sanitary RTD Sensors —Tri-Clamp, Hygienic Thread & Flush-Mount

Thermometrics sanitary RTD assemblies are manufactured to 3-A Symbol standards and FDA 21 CFR 177 material requirements for direct contact with food, beverage, pharmaceutical, and biotech process streams. Electropolished 316L SS wetted surfaces, hygienic process connections, and full validation documentation.

3-A Symbol AuthorizedFDA 21 CFR 177Tri-Clamp ½" to 4"Ra ≤ 0.8 µm ElectropolishedCIP / SIP RatedPt100 Class A

Model Series

Sanitary RTD Model Selection

Model	Connection Style	Wetted Material	Seal	IP Rating	Application
RTD-S10	Tri-clamp (½" to 4" ISO 2852)	316L SS, Ra ≤ 0.8µm EP	EPDM (std) · Silicone · PTFE	IP67	General dairy, pharma, biotech process
RTD-S11	DIN 11851 Hygienic Thread	316L SS, Ra ≤ 0.8µm EP	EPDM	IP67	European dairy and food equipment
RTD-S12	Varivent® N (GEA-type)	316L SS, Ra ≤ 0.8µm EP	EPDM or PTFE	IP67	Tank nozzle, inline vessels
RTD-S20	Flush-mount / Van Stone weld-in	316L SS, Ra ≤ 0.5µm EP	Integral (no external gasket)	IP69K	Tanks, fermenters, no dead-leg installations
RTD-S30	Spring-loaded, tri-clamp body	316L SS, Ra ≤ 0.8µm EP	EPDM	IP67	Vessel wall contact, CIP verification points

Specifications

Sanitary RTD Technical Data

Parameter	Specification
Sensing Element	Pt100 IEC 60751 Class A (standard) · Class B available
Wire Config	3-wire standard; 4-wire for highest accuracy
Wetted Material	316L SS — heat number traceable
Surface Finish	Ra ≤ 0.8 µm electropolished (standard); ≤ 0.5 µm on request
Seals / O-Rings	EPDM standard; Silicone; PTFE (FDA-grade)
Temperature Range	−50°C to 200°C (standard process)
Pressure Rating	To 150 PSI (10 bar) with standard tri-clamp
CIP Compatibility	Rated for NaOH (2%), HNO₃ (1%), peracetic acid CIP agents
SIP Compatibility	Steam sterilization to 135°C / 3 bar
IP Rating	IP67 std; IP69K (high-pressure washdown) on request
Head / Transmitter	Polycarbonate head (std); DIN-rail transmitter insert available

Validation Documentation Package

Material Certificate (316L SS)Heat number traceable
Surface Roughness ReportRa, instrument, date
Certificate of ConformanceStandard all orders
Dimensional Inspection ReportOn request
Calibration CertificateNIST-traceable Pt100
3-A Symbol AuthorizationApplicable configurations

No Dead-Leg Design

Dead legs — stagnant pockets in sanitary piping — are a primary concern in CIP system validation. Thermometrics flush-mount and Van Stone weld-in RTDs (RTD-S20) eliminate the pocket volume created by an insertion probe, ensuring complete drainage and CIP solution coverage of all wetted surfaces. Required for USP <1116> and EU GMP Annex 1 compliance in critical pharmaceutical installations.