HM SERIES — MICRO-FUSED TECHNOLOGY
HM24 Low Cost Pressure Transmitter
The HM24 delivers reliable pressure measurement at an exceptional price point — built with Germany’s HMK micro-fused silicon sensing technology on a monolithic 316L stainless steel structure. With ±0.5% FS accuracy across ranges from 100 kPa to 70 MPa and both mV and amplified output options, it serves as the ideal cost-effective solution for OEM integration, HVAC, water treatment, and general industrial applications.
0–70 MPa
Max Range
±0.5% FS
Accuracy
4-20mA / 0-5V
Output Signal
IP67
Protection
Product Overview
The HM24 Low Cost Pressure Transmitter establishes a new benchmark in performance-to-price ratio for both high-volume OEM applications and general industrial use. Built on Germany’s HMK micro-fused silicon piezoresistive sensing technology, the HM24 bonds a precision silicon die to a monolithic 316L stainless steel diaphragm using high-temperature glass — completely eliminating O-rings, silicone oil fill, and internal welds that are common failure points in conventional transmitters.
This glass-fused construction provides exceptional long-term stability (±0.25% FS/year) while maintaining excellent resistance to thermal cycling, humidity, and corrosive media. The all-welded stainless steel wetted path ensures leak-proof operation across the full 100 kPa to 70 MPa range, making the HM24 suitable for aggressive media including mildly corrosive liquids, steam, and contaminated water.
Available with both millivolt (raw sensor) and amplified outputs (4-20 mA, 0-5 V, 0.5-4.5 V, 1-5 V), the HM24 serves dual roles: as a low-cost pressure sensor for direct circuit integration, and as a complete transmitter for industrial process monitoring. Optional intrinsic safety certification (Ex ia IIC T5) extends its use into hazardous environments. Compared to competing economy transmitters, the HM24 delivers superior overload tolerance (2× FS) and a wider operating temperature range (-20 to +85°C) without compromising on accuracy.
Technical Specifications
| Parameter | Specification |
|---|---|
| Measuring Range | 0–100 kPa … 70 MPa |
| Pressure Type | Gauge or Absolute |
| Overall Accuracy | ±0.5% FS (non-linearity + hysteresis + repeatability, typical) |
| Long-Term Stability | ±0.25% FS / year |
| Overload Capacity | 2× Full Scale |
| Output Signal | 4–20 mA / 1–5 V / 0–5 V / 0.5–4.5 V / mV (raw sensor) |
| Power Supply | 12–36 VDC (amplified, typically 24 VDC) / 5 VDC (mV sensor) |
| Operating Temperature | -20 to +85°C |
| Compensated Temperature | -10 to +50°C |
| Temperature Coefficient | Zero: ±0.04% FS/°C (typ), ±0.06% FS/°C (max); Span: same |
| Thermal Hysteresis | ±0.1% FS (typical) |
| Response Time | ≤ 3 ms |
| Wetted Materials | 316L Stainless Steel (monolithic, no O-rings) |
| Process Connection | M20×1.5 / G1/4 / custom |
| Electrical Connection | PG7 cable entry / DIN 43650 connector |
| Protection Grade | IP67 (cable type) / IP65 (connector type) |
| Load Resistance | ≤ (U − 12) / 0.02 Ω (4-20 mA output) |
| Insulation Resistance | 100 MΩ @ 500 VDC |
| Weight | Approx. 250 g |
| Certifications | CE; optional Ex ia IIC T5 (intrinsic safety) |
Key Features
Micro-Fused Glass Bonding
German HMK silicon sensing element is permanently bonded to 316L SS diaphragm via high-temperature glass — no silicone oil, O-rings, or adhesive seals. Eliminates common failure modes from thermal cycling and chemical attack.
Monolithic 316L SS Construction
Entire wetted path is single-piece 316L stainless steel — no internal welds, no joints. This leak-proof design handles aggressive media including contaminated water, steam, and mildly corrosive fluids.
Multi-Output Flexibility
Choose between raw millivolt output for direct OEM circuit integration, or factory-calibrated amplified signals: 4-20 mA (2-wire), 1-5 V, 0-5 V, and 0.5-4.5 V (ratiometric). Single hardware platform serves diverse system architectures.
Cost-Optimized for Volume
Engineered for high-volume procurement with competitive per-unit pricing while maintaining industrial-grade performance. Ideal for OEM integrators who need thousands of units without sacrificing quality.
Wide Pressure Range Coverage
A single product family covers 100 kPa to 70 MPa (10,000 psi) in both gauge and absolute configurations. 2× overload capacity provides a built-in safety margin against pressure spikes.
Optional Intrinsic Safety (Ex ia)
Available with Ex ia IIC T5 intrinsic safety certification for deployment in Zone 0/1 hazardous areas. Requires an IS barrier for power supply — no additional explosion-proof housing needed.
Applications
Pumps & Compressors
Monitor discharge and suction pressures in industrial pump stations and air compressors. The fast 3 ms response time captures transient pressure events, while the monolithic SS construction withstands vibration.
Hydraulic & Pneumatic Systems
Reliable pressure feedback for hydraulic power units, pneumatic actuators, and fluid power circuits. Available up to 70 MPa for high-pressure hydraulic applications with 2× overload protection.
Water & Wastewater Treatment
Measure pipeline pressure, filter differential pressure, and pump head across water treatment facilities. 316L SS wetted parts resist chlorinated water and mild chemical exposure.
HVAC & Refrigeration
Monitor refrigerant pressures (including Freon and ammonia systems) in commercial HVAC units, chillers, and cold storage. Compatible with common refrigerant media through all-SS wetted path.
OEM & Automated Test Systems
The mV output option enables direct integration into custom electronics and automated test benches. Low cost per unit enables deployment across hundreds of test channels without budget constraints.
Agricultural Equipment
Withstands outdoor exposure and vibration in farming machinery — tractors, irrigation systems, and fertilizer injection pumps. IP67 cable version handles dust and moisture in field conditions.
Ordering Guide
Use the model code structure below to specify your HM24 configuration. Example: HM24 T (0~1.6MPa) — 1 — A1 — F1 — W1
| Selection Code | Options |
|---|---|
| Product Type | T = Transmitter (amplified output) | S = Sensor (mV output) |
| Pressure Type | Gauge (default, G optional) | A = Absolute |
| Measuring Range | 0–100 kPa, 0–160 kPa, 0–250 kPa, 0–400 kPa, 0–600 kPa, 0–1 MPa, 0–1.6 MPa, 0–2.5 MPa, 0–4 MPa, 0–6 MPa, 0–10 MPa, 0–16 MPa, 0–25 MPa, 0–40 MPa, 0–60 MPa, 0–70 MPa |
| Accuracy | 0 = 1% FS | 1 = 0.5% FS |
| Output Signal | A1 = 4-20 mA | V1 = 1-5 V | V2 = 0-5 V | V3 = 0.5-4.5 V | V4 = mV (sensor only) |
| Process Connection | F1 = M20×1.5 | F2 = G1/4 | F0 = Custom (specify) |
| Electrical Connection | W1 = Cable type, IP67, 2 m | W2 = DIN 43650 connector, IP65 |
| Additional Options | E = Intrinsic safety (Ex ia IIC T5, requires IS barrier) |
Note: Media must be compatible with 316L stainless steel. For custom ranges, special threads, or volume pricing, please contact our engineering team.
Frequently Asked Questions
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