At a Glance. Both are Endress+Hauser's flagship flowmeters, but they measure different things. The Promass F 100 is a Coriolis meter: it reads mass flow directly (plus density), at ±0.10% accuracy, on conductive and non-conductive liquids alike — in line sizes DN8 to DN80. The Promag P 100 is an electromagnetic flowmeter (EMF): it reads volumetric flow at ±0.5%, only on conductive liquids, but scales to much larger lines — DN15 to DN600 — at a fraction of the price per DN. The rule: custody transfer, batching, non-conductive media or when you need density → Promass; big pipes, dirty conductive liquids, cost-sensitive volume metering → Promag.
1. Head-to-Head Specification Table
| Specification | Promass F 100 (Coriolis) | Promag P 100 (EMF) |
|---|---|---|
| Measured quantity | Mass flow (+ density) | Volumetric flow |
| Accuracy | ±0.10% of reading | ±0.5% of reading |
| Repeatability | ±0.05% | ±0.1% class |
| Media conductivity | Any (conductive or not) | Conductive liquids only (≥5 µS/cm) |
| Nominal diameter | DN8 to DN80 | DN15 to DN600 |
| Process temperature | −50 °C to +205 °C | −40 °C to +130 °C |
| Wetted material | Stainless tube, no moving parts | PTFE liner, no moving parts |
| Output | HART, Modbus RS485 | HART, Modbus |
| Approvals | ATEX, IECEx, FM, CSA | ATEX, IECEx, FM |
| Stock page | Promass F 100 | Promag P 100 |
2. Two Principles, Two Answers
Coriolis (Promass F 100). The fluid flows through an oscillating measuring tube; the resulting phase shift is directly proportional to mass flow, and the oscillation frequency yields density as a bonus. Nothing about the fluid must be conductive, so oils, solvents, liquefied gases and food products are all fair game. Because the primary reading is mass, temperature or density fluctuations do not distort the result — which is why Coriolis owns custody transfer and batching duties.
Electromagnetic (Promag P 100). Faraday's law: a conductive liquid moving through a magnetic field induces a voltage proportional to volumetric flow. The measurement is immune to density, viscosity, pressure and temperature changes of the fluid, and the full-bore PTFE-lined meter presents virtually no pressure loss — ideal for wastewater, slurries, pulp and aggressive chemicals. But it has a hard physical precondition: the liquid must conduct. Hydrocarbons, demineralized water and non-conductive chemicals simply cannot be measured.
3. Selection by Application
| Your application | Recommended meter |
|---|---|
| Custody transfer, fiscal metering, recipe batching | Promass F 100 (±0.10% mass, density output) |
| Oils, solvents, fuels — non-conductive media | Promass F 100 (EMF physically impossible) |
| Wastewater, sludge, pulp, mining slurry | Promag P 100 (full bore, PTFE, DN up to 600) |
| Large-diameter lines above DN80 | Promag P 100 (Coriolis cost grows steeply with DN) |
| High or low temperature beyond +130 °C | Promass F 100 (−50 to +205 °C) |
| Volume metering of conductive chemicals, DN15-80 | Either — pick by accuracy need and budget |
4. Cost and Lifecycle Considerations
Unit price: at DN50 and above, an EMF costs a fraction of a same-size Coriolis; below DN50 the gap narrows. Lifecycle: both are zero-maintenance (no moving parts), but the Promass adds value by outputting density — replacing a separate densitometer in concentration and blending duties. Installation: the Promag needs full pipe and conductivity (≥5 µS/cm); the Promass is sensitive to external vibration on small lines and should be mounted away from strong pulsation sources.
For level duties on the same plant, the natural companions are the Micropilot FMR62 radar or FDU91 ultrasonic sensor, with PMC51B handling pressure and iTHERM TM131 temperature — one vendor, one toolchain.
5. Replacement and Cross-Reference
Common crossover requests:
- Mechanical meters (PD, turbine) being retired: replace with Promass F 100 when accuracy or density matters, or Promag P 100 for conductive liquids at volume accuracy — both remove the moving parts that drive maintenance.
- Legacy Promass 83 / Promag 50: the F 100 / P 100 100-series are the current successors with the same transmitter platform; process connections are matched by order data, not assumed.
Send Glorient the old meter's nameplate (model, DN, liner/tube, connection) and we will quote the closest in-stock successor within one business day.
6. FAQ
Can the Promag P 100 measure diesel or oil?
No — electromagnetic meters require conductive liquid (roughly ≥5 µS/cm). Hydrocarbons are non-conductive, so use a Coriolis meter like the Promass F 100 for fuels and oils.
Which meter for custody transfer?
Coriolis. The Promass F 100's ±0.10% mass accuracy with ±0.05% repeatability meets custody-transfer expectations; volumetric EMF accuracy drifts with temperature-dependent density.
Do both meters work with an existing HART DCS?
Yes — both output 4-20 mA with HART and Modbus RS485, integrating with any HART-capable control system without gateways.
Need a quote? Browse in-stock Endress+Hauser flowmeters and process instruments — Promass, Promag, Micropilot and more — or send your line list for a same-week quotation.