Pressure Instruments

Products › Pressure instruments

Instranova builds pressure instruments for the full temperature range, from liquid hydrogen at −253 °C to furnace gas at 800 °C, in gauge, absolute and differential types. This page is the starting point: pick the product series by process temperature and measurement type, then open the page that matches for real ranges, materials and models. If you are not sure, send us the five details in the checklist below and we will recommend the right series.

Choosing a pressure instrument

Start with two questions: what is the process temperature, and which reference do you need. Temperature decides the series, because a cell that reads ambient process fails on cryogenic or hot service without isolation. Reference decides the type: gauge against atmosphere for line and open-tank work, absolute against vacuum for sealed or vapor-pressure service, and differential between two points for flow, closed-tank level and filter monitoring. The three series below cover the temperature axis; each page covers gauge, absolute and differential within it.

Pressure instrument series

Differential pressure and level

Two-port measurements: flow across primary elements, closed-tank level, filter health, and the seal systems that keep aggressive media away from the cell.

Specialty and OEM lines

Built per application: legacy-pattern replacement, OEM design-ins, ultra-high pressure, hygienic service, clogging media and polymer melt.

Find your series

	Cryogenic transducer	Pressure transmitter (SI-300)	High-temperature (SI-512H)
Process temperature	−196 / −252 °C (−260 special)	−20 to 85 °C	To 350 °C standard; custom to 800 °C
Range	0.2 to 200 MPa	−100 kPa to 100 MPa	1 kPa to 60 MPa
Accuracy	±0.25 / ±0.5% FS	±0.3 / ±0.5% FS	±0.25 / ±0.5% FS
Output	0–5 / 0–10 V, 4–20 mA	4–20 mA; 0.5–4.5 / 1–5 / 0–10 V	4–20 mA; 0–5 / 1–5 / 0–10 V
Protection	IP65 / IP67	IP65; Ex ia IIC T4 option	IP65
Typical use	LN₂, LOX, LNG, LH₂ tanks and lines	General process, water, gas	Furnace, exhaust, steam

Tell us the medium, temperature, range, accuracy and area classification, and we will point you to the right series and a configured model. Talk to our application engineers.

Looking for pressure switches rather than transmitters or sensors? Mechanical and electronic pressure switches for trip points, alarms, and interlocks are grouped in our pressure switch range.

FAQ

What is the difference between a pressure transducer and a transmitter?

They are functionally similar; the usual distinction is output. A transducer gives an unamplified or voltage signal (mV/V, 0–5 V), while a transmitter conditions the signal to a two-wire 4–20 mA current loop that resists noise over long cable runs. Most models on these pages are offered with either output; the dedicated OEM line is the SI-390 industrial pressure transducer.

Gauge, absolute or differential – which do I need?

Gauge reads against local atmosphere and suits most line and open-tank work. Absolute reads against vacuum, for sealed vessels and vapor pressure. Differential reads between two points, for flow elements, closed-tank level and filter monitoring; the dedicated units are the SMT3151DP differential pressure transmitter and the compact SI-801 DP sensor. For a vented-reference unit on the classic capacitive cell, the dedicated page is the SI-3151GP gauge pressure transmitter. Each series page covers all three; for closed-tank level the dedicated unit is the SMT3151LT DP level transmitter.

What if my media is hotter or colder than the sensor rating?

The cell does not have to touch the media. Heat-sink standoffs and condenser tubes handle hot lines, and the cryogenic line uses a low-temperature cell instead. Pick the series by media temperature first; the series page shows which mounting covers your point. Two duties get their own lines: molten polymer on an extruder takes a melt pressure transducer with the diaphragm sitting in the melt stream, and hot, corrosive or clogging media on a standard transmitter takes a diaphragm seal pressure transmitter. And above 100 MPa, the high pressure transducer line carries cone-sealed units to 1500 MPa. Hygienic points in food and pharma take the SI-350 sanitary pressure transmitter, flush-diaphragm and clamp-fitted; the threaded-port version of the same flush face is the SI-703 flush diaphragm pressure sensor.