At a Glance. The Endress+Hauser Cerabar PMC51B and the VEGA VEGABAR 82 sit in the same performance class: two-wire 4-20 mA HART pressure transmitters with ±0.1% accuracy and dry, ceramic-based sensing that avoids oil-fill migration issues. The practical differences are the measuring cell philosophy and the temperature window. The PMC51B leads with a metal measuring cell (ceramic optional) rated −40 °C to +85 °C, making it the broader-approval general-purpose transmitter. The VEGABAR 82 builds on VEGA’s CERTEC ceramic cell rated −40 °C to +130 °C, with strong overload and vacuum resistance — the usual pick for aggressive media and hydrostatic tank level. Both carry ATEX / IECEx / FM approvals, so hazardous-area certification rarely decides the choice.
1. Head-to-Head Specification Table
| Specification | E+H PMC51B | VEGA VEGABAR 82 |
|---|---|---|
| Accuracy | ±0.1% | ±0.1% |
| Measuring cell | Metal (ceramic optional) | CERTEC ceramic |
| Process temperature | −40 °C to +85 °C | −40 °C to +130 °C |
| Output | 4-20 mA HART | 4-20 mA HART |
| Approvals | ATEX, IECEx, FM, CSA | ATEX, IECEx, FM |
| Typical duty | General process pressure, gauge/absolute | Process pressure + hydrostatic level |
| Stock page | PMC51B | VEGABAR 82 |
2. Measuring Cell Philosophy: Metal vs Ceramic
PMC51B metal cell. A welded metal diaphragm transmits pressure to the sensing element, which makes the transmitter forgiving across a wide spectrum of process media and mechanical loads. Plants standardizing on one transmitter for gauges, absolutes and flush-mounted duty often choose the metal-cell route; the ceramic option exists where chemical resistance of the wetted parts becomes the priority.
VEGABAR 82 CERTEC ceramic cell. The sensing element is a monolithic ceramic disc. Because there is no oil fill, there is no fill-fluid to migrate or leak, no temperature hysteresis from fluid expansion, and the ceramic surface tolerates aggressive and adhesive media well. The trade-off historically was mechanical fragility — largely engineered out in current generations, which specify high overload and vacuum resistance — but on recurring pressure spikes with slurry-laden media, a metal diaphragm still has the conservative engineering vote.
3. Pressure Duty vs Hydrostatic Level Duty
This is where the two products actually diverge in field use:
- General process pressure (pump discharge, header pressure, filter differential): the PMC51B is the natural fit, particularly where the rest of the loop is E+H.
- Hydrostatic tank level (vented or closed tanks): the VEGABAR 82 was engineered alongside VEGA’s level portfolio, and its +130 °C ceiling covers hot water, condensate and CIP-cleaned vessels that stop a +85 °C transmitter.
- Non-contact alternative: when open-tank level must ignore density changes, both brands would steer you to radar — the VEGAPULS 64 on the VEGA side or the Micropilot FMR62 on the E+H side. Hydrostatic and radar are frequently combined on the same vessel as primary and verification measurement.
4. Replacement and Cross-Reference
Because both transmitters share the 4-20 mA HART interface, ±0.1% accuracy class and standard process connections, cross-brand replacement is mostly a mechanical exercise. Before ordering a crossover, confirm:
- Range and units — match the calibrated span of the old transmitter;
- Process connection and seal (flange rating, flush vs extended nozzle);
- Temperature ceiling — applications above +85 °C rule out the PMC51B standard cell and point to VEGABAR 82;
- Hazardous-area certificate required by the loop (both hold ATEX/IECEx; PMC51B additionally lists FM/CSA).
Send Glorient the old nameplate (model, range, connection) and we will return the closest in-stock equivalent within one business day — including a like-for-like PMC51B or VEGABAR 82 quote with the same loop documentation.
5. Decision Summary
| Your situation | Recommended model |
|---|---|
| General process pressure, mixed media | PMC51B |
| Hydrostatic level, hot media up to +130 °C | VEGABAR 82 |
| Aggressive / adhesive media, no fill fluid | VEGABAR 82 (CERTEC ceramic) |
| E+H-standardized plant | PMC51B |
| Density-independent open tank level | VEGAPULS 64 or FMR62 radar |
6. FAQ
Is the VEGABAR 82 a suitable replacement for a PMC51B?
Yes in most loops — both are ±0.1%, 4-20 mA HART transmitters with ATEX/IECEx approvals. Match the calibrated range, process connection and temperature requirement first; above +85 °C the VEGABAR 82 is actually the better fit.
Why choose a ceramic cell over a metal diaphragm?
Ceramic cells have no oil fill, so they eliminate fill-fluid migration and give a faster, drift-free response on aggressive media. Metal diaphragms remain the conservative choice for severe pressure spikes and slurry service.
Can either transmitter measure level?
Both measure hydrostatic level from pressure head in vented or closed tanks. The VEGABAR 82 is positioned more strongly for level duty, while radar instruments like the VEGAPULS 64 remove density dependence entirely.
Need a quote? Glorient stocks Endress+Hauser Cerabar and VEGA VEGABAR transmitters with international shipping. Browse in-stock Endress+Hauser or browse in-stock VEGA, or send your tag list for a same-week quotation.