Processing temperature sensor signals from hazardous areas is the primary function of the Weidmuller 8965480000 ACT20X-2HTI-2SAO-S, a highly reliable 2-channel intrinsically safe temperature transducer. This module isolates, converts, and transmits temperature signals from RTD and thermocouple sensors located in Ex Zone 0, 1, or 2 to the safe area. It features dual-channel density in a compact 22.5 mm housing, providing active or passive 4-20 mA current outputs compatible with standard PLC and DCS analog input cards.
Key Features
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Dual-Channel Isolation: Two independent, galvanically isolated channels maximize channel density on the DIN rail.
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Intrinsically Safe Inputs: Certified for direct connection to temperature sensors in Zone 0, 1, and 2 hazardous locations.
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Universal Sensor Support: Configurable for Pt100, Pt500, Pt1000, Ni100 RTDs, and thermocouple types J, K, T, E, R, S, B, N, L, and U.
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Comprehensive Diagnostics: Integrated alarm functions detect line interruption, short circuits, supply voltage failure, and internal device errors.
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FDT/DTM Configuration: Easily parameterized using standard FDT/DTM software via the front-facing service interface.
Industrial Applications
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Chemical Processing: Monitoring reactor vessel temperatures in explosive atmospheres.
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Oil & Gas: Temperature measurement on offshore platforms, pipelines, and storage tank farms.
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Power Generation: Exhaust gas and bearing temperature monitoring in hazardous turbine enclosures.
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Water & Wastewater: Digester and chemical treatment plant temperature telemetry.
Technical Specifications
| Parameter |
Specification |
| Manufacturer |
Weidmuller |
| Article Number (SKU) |
8965480000 |
| Model Code |
ACT20X-2HTI-2SAO-S |
| Number of Channels |
2 |
| Supply Voltage |
19.2 to 31.2 V DC |
| Power Consumption |
≤ 1.4 W |
| Input Types |
RTD (Pt100, Pt500, Pt1000, Ni100), Thermocouples (J, K, T, E, R, S, B, N, L, U) |
| Output Signal |
4 to 20 mA (Active or Passive) |
| Step Response Time |
≤ 400 ms (current input), ≤ 1 s (temperature input) |
| Nominal Switching Voltage |
≤ 125 V AC / 110 V DC |
| Continuous Current |
≤ 0.5 A AC / 0.3 A DC |
| Connection Type |
Screw connection |
| Clamping Range |
0.5 mm² to 2.5 mm² |
| Flammability Rating |
V-0 |
| Protection Degree |
IP20 |
| Operating Temperature |
-20 to +60 degC |
| Humidity |
0 to 95% (non-condensing) |
| Dimensions (H x W x D) |
119.2 mm x 22.5 mm x 113.6 mm |
| Weight |
0.180 kg |
| Shipping Weight (Calculated) |
1.200 kg |
Connections and Interfaces
| Terminal Block |
Terminal Pin |
Function / Circuit Assignment |
| Hazardous Area (Input) |
11, 12, 13, 14 |
Channel 1: RTD (2, 3, or 4-wire) / Thermocouple Input |
| 21, 22, 23, 24 |
Channel 2: RTD (2, 3, or 4-wire) / Thermocouple Input |
| Safe Area (Output & Power) |
41, 42 |
Channel 1: 4 to 20 mA Analog Output (Active/Passive) |
| 51, 52 |
Channel 2: 4 to 20 mA Analog Output (Active/Passive) |
| 31 (+), 32 (-) |
Device Power Supply (19.2 to 31.2 V DC) |
Empirical Engineering Insights
Alternative Models & Compatibility
The ACT20X-2HTI-2SAO-S is the dual-channel variant within Weidmuller's ACT20X intrinsically safe signal converter family. If only a single channel is required, the ACT20X-HTI-SAO-S (single-channel version) can be utilized to reduce hardware costs. Configuration profiles created in the FDT/DTM "WI-Manager" software are fully interchangeable between single and dual-channel models, simplifying commissioning when scaling up system architectures.
Application Pitfalls & Engineering Notes
When mounting multiple ACT20X modules side-by-side on a DIN rail, thermal management is critical. Although the device is rated up to +60 degC, dense installations with continuous 24V DC supply can lead to localized heat build-up. It is recommended to maintain a 5 mm ventilation gap between adjacent modules if the ambient cabinet temperature regularly exceeds 50 degC. Additionally, ensure the loop resistance of the passive output configuration does not exceed the maximum load limits specified for your DCS analog input card.
Commissioning & Wiring Tips
For thermocouple inputs, always ensure that the cold junction compensation (CJC) is correctly configured in the DTM software. If using internal CJC, ensure the terminal block connections are tight and shielded from direct drafts or external heat sources, which can induce measurement drift. For RTD inputs, utilizing a 3-wire or 4-wire connection configuration is highly recommended to automatically compensate for lead wire resistance over long field runs.
Installation Guidelines
CRITICAL WARNING
De-energize all power sources before mounting, wiring, or configuring the device. Ensure strict separation between intrinsically safe (Ex i) field wiring and non-intrinsically safe safe-area wiring in compliance with EN/IEC 60079-14. Failure to maintain physical separation can compromise the explosion protection barrier.
1
Mount the ACT20X module vertically onto a standard TS 35 DIN rail, ensuring the locking foot securely clicks into place.
2
Connect the hazardous area temperature sensor wiring to the blue Ex-input terminals (11-14 and 21-24) using shielded, twisted-pair cables.
3
Wire the safe-area analog outputs (41-42 and 51-52) and the 24 V DC power supply (31-32) to the black terminals.
4
Connect the configuration interface to a PC running Weidmuller WI-Manager (FDT/DTM) to set the sensor type, range, and alarm thresholds.