RenKe RK-PM300 Industrial Pressure Transmitter with Integrated Temperature Sensing

Overview

The RenKe RK-PM300 is an industrial-grade pressure transmitter engineered for high-reliability process monitoring in demanding environments. It utilizes a piezoresistive silicon sensing element with a stainless steel (316L) isolation diaphragm, providing stable and repeatable output across extended operating cycles. The sensor core incorporates factory-applied temperature compensation algorithms to minimize thermal drift—critical for applications where ambient or media temperature fluctuations exceed ±10 °C. Calibration is performed using traceable, high-accuracy pneumatic or hydraulic pressure standards at multiple points across the full span, ensuring compliance with ISO/IEC 17025–accredited metrological practices. Designed for universal deployment, the RK-PM300 supports gauge, vacuum, and absolute pressure measurement modes, enabling integration into closed-loop control systems, safety interlocks, and data acquisition networks across fluid power, chemical processing, and energy infrastructure.

Key Features

• Piezoresistive silicon sensing technology with welded 316L stainless steel diaphragm for long-term stability and corrosion resistance
• Integrated temperature sensing at the pressure inlet port—enabling synchronized acquisition of pressure and local media temperature without external probes
• Wide configurable pressure range: –0.1 MPa (vacuum) to +60 MPa (gauge), supporting both low-pressure HVAC and high-pressure hydraulic applications
• RS-485 digital interface compliant with Modbus RTU protocol (slave ID configurable, baud rate up to 115.2 kbps), facilitating direct connection to PLCs, SCADA HMI systems, and industrial gateways
• Robust electrical protection: reverse polarity protection, transient overvoltage suppression (per IEC 61000-4-5 Level 3), and short-circuit current limiting
• IP54-rated enclosure with stainless steel housing—suitable for indoor industrial enclosures and protected outdoor installations
• Operating supply voltage range of 10–30 VDC, compatible with standard 24 VDC control system power rails
• Overpressure tolerance up to 2× full-scale rating without permanent zero shift or sensitivity degradation

Sample Compatibility & Compliance

The RK-PM300 is chemically compatible with non-corrosive gases (e.g., air, nitrogen, natural gas) and liquids (e.g., water, hydraulic oil, glycol-based coolants) when matched with appropriate wetted materials (316L SS diaphragm, FKM or EPDM seals). It is not rated for aggressive halogenated solvents, strong oxidizers, or molten metals. The device meets electromagnetic compatibility requirements per IEC 61000-6-2 (immunity) and IEC 61000-6-4 (emissions), and conforms to RoHS 2011/65/EU directive for hazardous substance restriction. While not certified to ATEX or IECEx for explosive atmospheres, it may be deployed in Zone 2/Class I, Division 2 environments when installed behind approved barriers. For regulated industries, its deterministic Modbus RTU output supports audit-ready data logging when paired with compliant SCADA or historian systems adhering to 21 CFR Part 11 principles (electronic records & signatures).

Software & Data Management

The RK-PM300 operates as a standalone field device with no embedded firmware update capability—ensuring deterministic behavior and minimizing cybersecurity attack surface. Configuration (e.g., Modbus slave address, baud rate, pressure unit selection) is performed via ASCII command set over RS-485 using industry-standard terminal utilities (e.g., ModScan, QModMaster). Raw register data includes 16-bit scaled pressure (in kPa or psi), compensated temperature (°C), status flags (overrange, fault, calibration lock), and internal diagnostics. When connected to RenKe’s optional network concentrator (RK-NET-100), data is aggregated and transmitted via Ethernet or cellular LTE to the cloud-based RenKe Cloud Platform—accessible via HTTPS-secured web dashboard or native iOS/Android applications. All historical readings are timestamped with UTC synchronization and stored with ≥1-year retention; alarm events (e.g., pressure deviation >5% FS for >30 s) trigger email/SMS notifications and are logged with event correlation metadata.

Applications

• Constant-pressure water supply systems—monitoring pump discharge pressure and detecting cavitation or pipe rupture events
• Hydraulic power units—real-time tracking of system pressure and oil temperature to prevent thermal runaway and seal degradation
• Chemical reactor monitoring—synchronized pressure/temperature logging during exothermic batch processes per ASTM E2554 statistical process control guidelines
• Steam boiler feedwater control—gauge pressure feedback for cascade PID loops in ASME Section I-compliant installations
• Environmental monitoring stations—barometric pressure measurement with temperature compensation for meteorological correction algorithms
• Oil & gas wellhead telemetry—remote pressure surveillance in upstream gathering systems using low-bandwidth Modbus-over-RTU infrastructure

FAQ

What pressure types does the RK-PM300 support?

It measures gauge pressure (relative to atmospheric), vacuum (negative gauge), and absolute pressure—selected at time of order based on configured reference port design.
Is the RK-PM300 suitable for food-grade or pharmaceutical applications?

No—it lacks 3-A Sanitary Standard certification or FDA-compliant wetted material documentation (e.g., USP Class VI elastomers); use only in non-product-contact utility systems.
Can the temperature measurement be used independently of pressure?

Yes—the inlet port temperature value is available as a separate Modbus register (40003), decoupled from pressure scaling logic.
Does the device support HART or analog 4–20 mA output?

No—only digital RS-485 Modbus RTU output is provided; analog variants (RK-PM300A) are available separately.
What is the maximum recommended cable length for RS-485 communication?

2000 meters with proper twisted-pair shielded cable (AWG22, 120 Ω characteristic impedance) and termination resistors at both ends.