Efficient phase separation under extreme conditions – the STMd-T rod probe
Typical use of the application for phase separation
Highest reliability in phase separation for demanding chemical processes. The rod probe type: STMd-T from Aquasant is the ideal solution for process engineers who require the highest precision and reliability in interface measurement in demanding chemical processes. Thanks to its full PTFE design, this probe is particularly suitable for use in environments with aggressive chemicals.
This advanced probe ensures continuous phase control in glass-lined or PTFE-lined decanters by precisely measuring the phase height using impedance measurement. Whether emulsions, phase inversions or other complex process conditions – the STMd-T ensures reliable and optimal phase separation.
- Chemicals
- Petro Industry
- Pharmaceuticals
- Pilotplan
- Production
- Refinery
High-quality materials for extreme conditions
Adaptability is the key to success in the chemical industry. That’s why the STMd-T offers a customized sensor design that is precisely tailored to your process requirements to ensure maximum results and process reliability. The combination of stainless steel, Teflon sheathing and the FFKM (Chemraz) double sealing system ensures that the probe performs reliably even under extreme chemical conditions.
Precision in the measurement and differentiation of liquid phases
With the ability to accurately measure impedance, conductivity and dielectric constant (DK) as a sum signal, the STMd-T rod probe allows you to clearly distinguish between different liquid interfaces – from insulating to highly conductive products. This provides you with valuable data that can significantly improve the efficiency and quality of your processes.
Specifications
- Physical measuring principle: Impedance
- Process connections: Flanges or threads (metric/inch)
- Process pressure: 0.5 to +40 bar
- Measuring range: 40 to 3000 mm
- Temperature: -20 to +170 °C
- 2-wire technology
- ATEX

“Learn more about precise interface measurement and optimize your phase separation with the STMd-R rod probe. Contact us now for an individual consultation and maximize the efficiency of your chemical processes.”
– Roger Inauen
Information
Technical Data
Documentation
Accessoires
Information
Advantages of phase separation with Aquasant sensors
- High measuring accuracy: The impedance measurement reliably detects even the smallest differences in density and mulch layers.
- Reliable phase monitoring: Continuous phase monitoring takes place online and ensures automatic, fast and reliable detection of the interfaces, even under difficult conditions.
- Universal use: Our full PTFE rod probes are versatile – in decanters, mixer-settlers, columns or pipelines.
- Simple integration: Easy commissioning and the self-monitoring measuring and control unit guarantee reliable liquid/liquid phase separation in various industrial processes.
Control units
MIL 8130 | MIQ 8130
MIPROMEX – The all-rounder for interface measurement
The MIQ evaluation unit can be used for everything from interface level measurement to batch separation with a pipe probe. With the option of a 2nd measuring circuit, phase monitoring, the fill level or the separation behavior can be measured. The evaluation electronics not only serve as a power supply unit in 2-wire technology, but also contain the intelligence for data processing.
Your advantage: High cost-effectiveness and investment security thanks to a long service life.
- Universally applicable, reduced storage costs
- With 1 or 2 measuring inputs
- Fault visualization, fault messages can be set to analogue output
- Monitored measuring circuit from probe to relay
- Analog output 4 – 20 mA with galvanic isolation, max. load 750 Ohm
- 2 relay outputs with potential-free changeover contact Limit value on first measuring circuit
- Continuous interface monitoring
- Phase monitoring for safety-optimized separation
- Combination with level measurement of the upper phase
Ex version: SEV 22 ATEX, EMC, CE

Technical Data
-
DimensionsDN25-165
ANSI 1"-5"
or according to process specification:
Thread M/G/R/NPT (metric/inch)
Triclamp
Milk pipe fitting -
Pipe classShape according to EN 1092-1
ASTM A182, ASME B16.5 RF
-
Probe materialStainless steel 316L fully PTFE coated
-
Measurement electronicsconstructed aluminum
-
Protection classIP 68 (0.2 bar)
-
Ambient temperature-20.. 60°C
-
Measurement principleImpedance
-
Process temperature range-20..100°C Standard
-
Process pressure range-0.5..40 bar
-
Seals"FKM
FFKM (Chemraz, Kalrez)
-
Measuring electrode materialPTFE
-
Maximum measuring length40 .. 3000 mm
-
Measuring rangeDK >1.8
-
Conductivity rangeorganic phase at TN: 0..50 µS/cm (constant)
-
Integration time40-400 ms
-
Ex-proofIntrinsic safety ""i""
Flameproof enclosure "" d"" -
Scope of applicationATEX / Europe
IEC / worldwide
UKCA Great Britain -
CertificatesDeclaration of conformity (FDA/EU1935)
Confirmation TSE/BSE free
Pressure test certificate
Manufacturer conformity PED/DESP/PED
Tool certificate 2.2 (EN 10204)
Acceptance test certificate 3.1
Test certificate ferrite content
Test certificate surface quality roughness
Test certificate welded joint -
Electrical outputsmipromex: 4-20 mA active/2 GW USK relay or OC
MTI: Pulse
Documentation
PDF Downloads
Downloads
- Flyer Separation layer continuous separation
- Probe data sheet general STM
- Data sheet probe STMd SB T DN
- MIQ control unit data sheet
- Data sheet control unit MIL
- Betriebsanleitung kurz MIL/MIQ
- Operating instructions MIL/ MIQ
- Ex-documentation
Accessoires
- mipromex evaluation unit type: MIQ/MIL 8130
- Monorack top-hat rail enclosure type: MRM 2
- Local measuring electronics type: MTI 100/x AEO2
