RTD-Flush-Mount

Supported Applications

The ACI Platinum Flush Mount Button Series provides temperature sensing for HVAC and building management systems where a low-profile, aesthetically discreet installation is required. These sensors are designed to be easily hidden or blended into the environment using included mounting kits that allow flush integration with surfaces.

Engineers select this series when compensating for external lead wire resistance in 3-wire configurations connected to temperature transmitters or PLCs (Programmable Logic Controllers). The double encapsulation process and thermally conductive epoxy are utilized to eliminate moisture effects on the sensor element while increasing response time.

Operating Conditions & Performance

The series operates within specific ambient ranges dependent on the enclosure material. ABS Plastic Button (PBS) models support an operating range of -40 to 70°C (-40 to 158°F), while Brass (BBS) and 304 Stainless Steel (SBS) models operate from -40 to 200°C (-40 to 392°F). Storage temperature for all variants is rated at -40 to 85°C (-40 to 185°F).

Performance specifications include a nominal response time of 8 seconds (63% step change) and Class A accuracy per DIN EN 60751 (IEC 751). The tolerance formula is defined as ±/°C = (0.15°C + (0.002 * |t|)), where |t| is the absolute value of temperature above or below 0°C in °C. Specific accuracy points include:

• -40°C (-40°F): ±0.23°C (±0.414°F)
• 0°C (32°F): ±0.15°C (±0.27°F)
• 70°C (158°F): ±0.29°C (±0.53°F)
• 200°C (392°F): ±0.55°C (±0.99°F)

Sensor stability is rated at ±/ 0.03% after 1000 Hours @ 300°C (572°F). The series operates in humidity ranges of 10 to 95% RH, non-condensing.

Configuration Options

The Platinum Flush Mount series is configurable across sensor resistance values, wire counts, and enclosure materials. Selection options include:

• Sensor Output @ 0°C (32°F): A/100-xW-XXX models provide 100 Ohms nominal; A/1K-xW-XXX models provide 1000 Ohms nominal.
• Wire Configuration: Two-wire options are non-polarity sensitive. Three-wire options (3W) are polarity sensitive and intended to compensate for external lead wire resistance in building management systems or PLCs.
• Housing Materials: Available in Brass (BBS), 304 Stainless Steel (SBS), or ABS Plastic (PBS). The plastic button carries a UL94-HB flammability rating.
• Electrical Connections: Features Etched Teflon (PTFE) colored leads with Mil Spec 16878/4 Type E insulation. Conductor material is Silver Plated Copper, sized at 22 AWG (0.65mm).
• Certifications & Options: Units carry CE, RoHS2, and WEEE approvals. An optional NIST Certificate (3 Points) can be ordered.

A universal mounting kit is supplied with the sensor to aid installation. For brass and stainless steel models, this includes a 3/8-16" Hex Jam Nut, one 1" Delrin Spacer/Insulator, and one 2" Delrin Spacer/Insulator.

Key Product Differences

Variants within the series are distinguished by sensor resistance (A/100 vs. A/1K), wire count (2W vs. 3W), and enclosure material (PBS, BBS, SBS). Physical dimensions differ between materials: ABS Plastic models measure 1.00" (25.4mm) x 0.750" (19mm), while Brass and Stainless Steel models measure 1.20" (30.48mm) x 0.700" (17.78mm). The process connection for metal housings is a 3/8-16 Thread.

Lead wire colors differentiate sensor types: A/100 models use Brown/Brown leads, while A/1K models utilize Black/Black or White/Yellow combinations depending on the specific configuration. ACI recommends using 18 AWG lead wires to reduce external resistance when installing these Platinum RTDs.