The KROHNE H250 M8 is the definitive compact variable area flowmeter designed for space-restricted process applications and OEM skids. This metal tube rotameter bridges the gap between pure mechanical reliability and modern digital integration. Whether you require the H250 M8M for power-free mechanical indication or the H250 M8E for a 4…20 mA/HART® linear analogue output, this meter ensures high-pressure stability (up to 145 barg) in a miniature footprint. It is the ideal solution for additives dosing, nitrogen inerting, and sample flow monitoring in chemical, oil & gas, and machinery sectors.
In modern industrial skids, space is a premium. The H250 M8 stands out with its short installation length, allowing it to fit where larger meters like the [KROHNE H250 M40] cannot. The M8E version utilizes sophisticated magnetic sensors to record float position without contact or hysteresis, providing a stable HART 7 signal for remote monitoring.
Constructed from materials such as 316L Stainless Steel, Alloy C4, and Titanium, the H250 M8 is built to handle corrosive acids and bases. With ATEX, IECEx, and NEPSI approvals, it operates safely in explosive atmospheres. Despite its small size, it maintains a SIL 2 safety rating, making it a trusted component for dry-run prevention and gas seal monitoring.
| Feature | Detailed Engineering Specification |
| Measurement Principle | Variable area float (Rotameter) |
| Primary Media | Liquids and Gases |
| Accuracy | ±2.5% (VDI/VDE 3513-2) or ±2% of Full Scale |
| Max Process Pressure | 145 barg / 2102 psig |
| Process Temperature | -40°C to +200°C / -40°F to +392°F |
| Turndown Ratio | 10:1 |
| Flow Ranges (Water) | 10 to 6,300 l/h (5 to 1664 GPH) |
| Flow Ranges (Air) | 0.7 to 180 m³/h (25 to 111 SCFH) |
| Wetted Materials | 316L, Alloy C4/C276, Alloy 400, Titanium, 6Mo |
| Nominal Sizes | DN15 to DN25 / ½" to 1" |
| Protection Class | IP66/67 (PPS or Stainless Steel housing) |
| Communication | 4…20 mA, HART®, Limit Switches |
| Safety Rating | SIL 2 certified |
Power Requirements: If your site lacks auxiliary power, choose the H250 M8M for 100% mechanical local indication. For SCADA integration, the H250 M8E (2-wire 4…20 mA) is required.
Material Compatibility: For chloridic substances or sulfuric acids, upgrade from 316L to Alloy C276.
Accuracy vs. Footprint: While the M8 is compact, for higher accuracy (±1.5%) in larger pipe sizes, consider the [KROHNE H250 M40].
Vertical Orientation: VA meters rely on gravity; install the H250 M8 in a strictly vertical upward flow position.
Straight Runs: Unlike electromagnetic meters like the [KROHNE WATERFLUX 3400], the H250 M8 requires minimal straight pipe runs (typically 5D/3D), saving significant space in modular skids.
Filter Installation: Since the float moves within a narrow tube, always install an upstream filter if the medium contains magnetic particles or large solids to prevent float blockage.
The H250 M8 is virtually maintenance-free due to its "no gasket" design and magnetic coupling. However, for 2026 predictive maintenance standards:
Float Inspection: Periodically check for deposits if measuring additives or catalysts.
Diagnostic Verification: Use the KROHNE OPTICHECK Flow Mobile App wirelessly to verify device electronics without process interruption.
Q: What is the main difference between the KROHNE H250 M8 and M40?
A: The H250 M8 is specifically designed for space-restricted installations and lower flow ranges (up to 6,300 l/h water). It features a shorter installation length, making it the perfect choice for compact OEM skids. For larger pipe sizes and extreme temperatures up to +400°C, the [KROHNE H250 M40] is the recommended alternative.
Q: Can the H250 M8 operate without any electrical power?
A: Yes. The H250 M8M version is a purely mechanical flowmeter. It uses a magnetic coupling to display flow on a local scale without needing an auxiliary power supply, ensuring critical flow monitoring during power outages.
Q: Is the H250 M8 suitable for measuring aggressive chemicals?
A: Absolutely. The measuring tube is available in a variety of corrosion-resistant materials, including 316L Stainless Steel, Alloy C276, and Titanium. Its "no gasket" all-metal construction further prevents leak paths when handling hazardous acids or bases.
Q: How do I verify the device status on a SCADA system?
A: By selecting the H250 M8E version, you get a 2-wire linear 4…20 mA output with HART® 7 communication. This allows for remote flow monitoring and device diagnostics compliant with NAMUR NE 107.
