Vaisala HMP110 Temperature and Humidity Transmitter

Overview

The Vaisala HMP110 is a compact, high-stability temperature and humidity transmitter engineered for reliable integration into OEM systems, environmental monitoring platforms, and controlled laboratory environments. Based on Vaisala’s proprietary HUMICAP® 180R capacitive polymer sensor and a precision Pt1000 RTD (Class F0.1 per IEC 60751), the HMP110 delivers traceable, long-term measurement stability under demanding conditions. Its operating principle relies on capacitance-based relative humidity detection — where water vapor absorption alters the dielectric constant of the polymer sensing layer — coupled with four-wire resistance thermometry for temperature. This dual-sensor architecture enables accurate dew point calculation (−40 to +80 °C) and supports real-time compensation of RH readings against ambient temperature variations. Designed for industrial robustness, the HMP110 features an IP65-rated stainless steel (AISI 316) housing and chemically resistant HUMICAP® sensor element, ensuring performance resilience in presence of alcohols, solvents, and organic vapors common in fermentation chambers, gloveboxes, and stability testing cabinets.

Key Features

• Compact cylindrical form factor (Ø12 mm × 71 mm) with M12×1 threaded mounting interface for rapid mechanical integration
• Ultra-low power consumption: typical current draw <1 mA (average), peak ≤5 mA — suitable for battery-operated data loggers and remote wireless nodes
• Fast thermal stabilization: analog output ready in ≤4 s (at nominal 15 VDC); digital RS485 output active in ≤1 s
• Dual-channel analog output configurable as independent voltage signals for temperature and humidity (e.g., 0–1 V for RH, 0–5 V for T)
• Optional RS485 Modbus RTU interface supporting multi-drop configurations and remote configuration via Vaisala Insight PC software
• HUMICAP® 180R sensor provides superior chemical tolerance and long-term drift stability (<0.1 %RH/year typical) without requiring periodic recalibration under normal use
• Factory-calibrated with ISO/IEC 17025-accredited certificate; full traceability to national metrology institutes (NMI) aligned with CIPM MRA framework
• Modular probe design: HMP110R replacement probe maintains measurement continuity and simplifies maintenance without system disassembly

Sample Compatibility & Compliance

The HMP110 is validated for continuous operation across a wide range of sample environments — including inert gas gloveboxes (N₂, Ar), humidified CO₂ incubators, pharmaceutical stability chambers (ICH Q1), bioreactor headspaces, and greenhouse microclimates. Its stainless steel body and chemically inert HUMICAP® sensor tolerate exposure to ethanol, isopropanol, acetic acid vapor, and low-concentration formaldehyde — making it suitable for fermentation process monitoring per ASTM E2912 and ISO 20607. Electromagnetic compatibility conforms to EN 61326-1 (industrial environment). While not intrinsically safe, its low-energy design meets functional safety requirements for non-hazardous area installations per IEC 61000-6-2/-4. The device supports GLP/GMP documentation workflows through audit-trail-capable calibration records and version-controlled firmware updates.

Software & Data Management

Vaisala Insight software (Windows-based) enables configuration, real-time monitoring, and firmware updates via USB-to-RS485 adapter. For analog-output units, integration with SCADA, PLC, or DAQ systems is achieved using standard voltage input modules. RS485-equipped models support up to 32 devices on a single bus, with configurable baud rates (9.6–115.2 kbps) and parity settings. All digital communication adheres to Modbus RTU protocol (function codes 03h/04h for register read, 06h/10h for write), enabling seamless interoperability with industrial automation platforms (e.g., Siemens S7, Rockwell ControlLogix). Raw sensor data — including compensated RH, temperature, dew point, and sensor diagnostics — are accessible via holding registers. Firmware versions include built-in self-diagnostics (sensor health flag, open-circuit detection, supply voltage monitoring) compliant with IEC 61508 SIL1 functional safety principles.

Applications

• OEM integration into environmental test chambers (ASTM D4332, ISO 187, ICH Q1A–Q1E)
• Continuous monitoring in GxP-regulated stability storage rooms and accelerated aging studies
• Humidity control feedback loops in HVAC systems for cleanrooms (ISO 14644-1 Class 5–8)
• Biological incubators and CO₂ culture systems requiring tight RH control (±2 %RH)
• Portable data loggers and IoT-enabled environmental nodes with extended battery life (>2 years on 2×AA Li-SOCl₂)
• Pharmaceutical lyophilization chamber mapping and validation (per FDA Guidance for Industry: Process Validation)
• Microclimate monitoring in botanical greenhouses and vertical farming infrastructure

FAQ

Does the HMP110 require periodic recalibration?
No routine recalibration is required under normal operating conditions. The HUMICAP® 180R sensor exhibits low drift (<0.1 %RH/year). However, users operating in aggressive chemical environments or after physical damage should perform verification against a reference hygrometer per ISO 5725 or schedule recalibration every 12–24 months.
Can the HMP110 be used in pressurized or vacuum environments?
The HMP110 is rated for ambient pressure operation only (101.3 kPa ±10 %). It is not designed for direct use inside vacuum chambers or high-pressure vessels. For such applications, consult Vaisala’s HMP300 series with dedicated pressure-compensated variants.
Is the RS485 option compatible with Modbus TCP gateways?
Yes — when paired with a certified RS485-to-Ethernet gateway (e.g., Moxa EDS-G205A), the HMP110 can be integrated into TCP/IP networks and accessed via standard Modbus TCP clients.
What is the maximum cable length for analog output without signal degradation?
For 0–5 V output with load ≥50 kΩ, maximum recommended cable length is 100 m using shielded twisted-pair (STP) cable. For longer runs or noisy environments, use the RS485 option or install a local signal conditioner.
Does the HMP110 support dew point output natively?
Dew point is calculated internally and available as a derived parameter via RS485 registers. Analog outputs provide only temperature and RH; external calculation is required if using voltage outputs exclusively.