HM SERIES — CERAMIC CAPACITIVE
HM26 High Temperature Ceramic Capacitive Pressure Transmitter
Ceramic capacitive sensing technology for harsh media — one of four methods commonly used for high-temperature pressure measurement. Al₂O₃ ceramic diaphragm with no silicone oil fill — inherently dry measurement immune to media contamination. From micro-pressure 0.5 kPa to 100 MPa, with ±0.1% FS accuracy and ≤±0.02% FS/°C temperature drift.
±0.1%Best Accuracy100 MPaMax Range125°CMedia TempAl₂O₃Ceramic
Ceramic Capacitive Sensing: No Oil, No Contamination
The HM26 uses an imported ceramic capacitive sensor that fundamentally differs from conventional piezoresistive transmitters. Instead of a silicone oil-filled cavity, the Al₂O₃ ceramic diaphragm directly contacts the process medium — eliminating the risk of oil leakage into food, pharmaceutical, or chemical processes.
This dry measurement principle delivers several advantages: exceptional overload capacity (pressure tolerance up to 200× rated range for micro-pressure models), media temperature tolerance to +125°C without oil degradation, and compatibility with corrosive media that would attack conventional sensing elements. The ceramic substrate meets food-contact requirements, making the HM26 suitable for hygienic applications.
Large capacitive signal output combined with PFM (Pulse Frequency Modulation) signal transmission and SMT thick-film electronics delivers ±0.1% FS accuracy with outstanding temperature stability (≤±0.02% FS/°C). Long-term drift stays within ±0.1% FS/year — reducing calibration frequency and lowering total cost of ownership.
Technical Specifications
| Parameter | Specification |
|---|---|
| Sensing Principle | Ceramic Capacitive (Al₂O₃) |
| Pressure Range | -100 kPa to 0 … 0.5 kPa to 100 MPa |
| Pressure Type | Gauge (G) / Absolute (A) / Compound (F) |
| Overload Capacity | 3× to 200× rated range (model dependent) |
| Accuracy | ±0.1% FS / ±0.25% FS / ±0.4% FS (select at order) |
| Long-term Stability | ≤ ±0.1% FS / year |
| Zero Temperature Drift | ≤ ±0.02% FS/°C |
| Sensitivity Temperature Drift | ≤ ±0.02% FS/°C |
| Output Signal | 4-20 mA / 1-5 V DC / 0-5 V DC / 0.5-4.5 V DC |
| Power Supply | 12–36 V DC (typical 24 V DC) |
| Load Resistance | ≤ (U-10) / 0.02 Ω |
| Response Time | ≤ 2 ms |
| Media Temperature | -40°C to +125°C |
| Ambient Temperature | -40°C to +85°C |
| Compensation Temperature | -20°C to +80°C |
| Diaphragm Material | Al₂O₃ Aluminum Oxide Ceramic |
| Housing Material | Low-copper Cast Aluminum |
| Wetted Material | 1Cr18Ni9Ti (equivalent to 321 SS) |
| Sealing | NBR / PTFE / FKM (application dependent) |
| Protection Rating | IP65 |
| Explosion-proof | Ex iaⅡCT5 (intrinsic safety) |
Key Features
125°C Media Temperature
Ceramic capacitive sensor handles media temperatures up to 125°C without silicone oil degradation. Ideal for steam, hot oil, and high-temperature process applications.
±0.1% FS Accuracy
High-performance accuracy with PFM signal transmission and SMT thick-film electronics. Temperature drift stays below ±0.02% FS/°C across the full compensation range.
Extreme Overload Protection
Micro-pressure models withstand 100–200× rated pressure without damage. Ceramic diaphragm flexes elastically without plastic deformation or zero shift.
Dry Measurement — No Oil Fill
Pure Al₂O₃ ceramic sensing element requires no silicone oil cavity. Eliminates oil leakage risk in food, pharma, and semiconductor processes.
Broad Chemical Compatibility
Al₂O₃ ceramic resists most acids, alkalis, and organic solvents. 1Cr18Ni9Ti wetted parts handle corrosive vapors and aggressive chemical media.
Intrinsic Safety Certified
Ex iaⅡCT5 explosion-proof certification for deployment in Zone 0/1 classified hazardous areas. Waterproof, dustproof, shockproof construction.
Applications
Food & Beverage Processing
Oil-free ceramic diaphragm meets food-contact requirements. Monitor pasteurization, CIP/SIP cleaning, and sterilization pressures without contamination risk.
Pharmaceutical Manufacturing
Hygienic dry measurement for bioreactor pressure, autoclave monitoring, and clean room differential pressure. No silicone oil leakage into sterile processes.
Chemical & Petrochemical
Broad chemical resistance handles aggressive acids, alkalis, and organic solvents. Intrinsic safety certification enables hazardous area installation.
Steam & Hot Fluid Systems
Media temperature rating to +125°C handles direct steam contact and hot thermal oil circuits without cooling elements or siphon tubes.
HVAC & Clean Environments
Micro-pressure capability from 0.5 kPa measures room differential pressure and filter loading in cleanrooms, hospitals, and data centers.
Water Treatment & Environmental
Corrosion-resistant ceramic withstands chlorinated water, wastewater, and acidic condensate. IP65 protection for outdoor installations.
Ordering Guide
Configure your HM26 using the code system below. Example: HM26-G-0~1.6MPa-2-A1-W2 = Gauge, 0–1.6 MPa, ±0.25% FS, 4-20mA, DIN 43650 plug.
| Selection | Code / Options |
|---|---|
| Pressure Type | |
| Gauge (default) | G |
| Absolute | A |
| Compound (+/-) | F |
| Range | |
| 0.5 kPa, 1 kPa, 2.5 kPa … 10 MPa, 25 MPa, 40 MPa, 60 MPa, 100 MPa | |
| Accuracy | |
| ±0.4% FS | 1 (Standard) |
| ±0.25% FS | 2 (High) |
| ±0.1% FS | 3 (Premium) |
| Output Signal | |
| 4-20mA | A1 |
| 1-5V | V1 |
| 0-5V | V2 |
| 0.5-4.5V | V3 |
| Electrical Connection | |
| Cable (IP67) | W1 |
| DIN 43650 plug (IP65) | W2 |
| Aviation connector | W3 |
| Special Options | |
| Ex iaⅡCT5 intrinsic safety | E |
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Frequently Asked Questions
Need a Ceramic Capacitive Pressure Solution?
The HM26 ceramic capacitive technology excels in corrosive media and high-temperature applications. Tell us about your process conditions and our engineers will recommend the optimal configuration. We typically respond within 12 business hours.