Micro Motion 4200 2-Wire Coriolis Transmitter

A loop-powered Coriolis transmitter for existing 4-20 mA wiring

The Micro Motion 4200 2-wire transmitter lets a Micro Motion Coriolis sensor run on a two-wire loop, with all electronics power supplied over the primary 4-20 mA signal. The datasheet describes it as a way to replace existing 2-wire flow devices without adding power or cabling, and states certification for SIL2 and SIL3 safety applications per IEC 61508. Multivariable and diagnostic data are carried over HART communications.

Technical specifications

Where a 2-wire Coriolis meter fits

The datasheet positions the 2-wire meter for chemical, petrochemical and refining plants and for continuous process and mass balance applications, where adding a Coriolis point to an existing loop is cheaper than new power cabling. A wireless THUM adapter option adds WirelessHART. Because the power budget is small, the 4200 offers fewer outputs than a field-mount unit; for a richer I/O set, compare the Micro Motion 4700 and the Micro Motion 5700 Coriolis flow transmitter. A barrier may be required in a hazardous area loop, as shown in the datasheet connection example.

For remote mounting the datasheet lists CMF010 to CMF350, CMFS007 to CMFS150, F025 to F400, H025 to H400, R025 to R300 and T075 to T150 sensors, and the stainless steel transmitter housing is offered for CMFS007 to CMFS150, F025 to F400, H025 to H400 and R025 to R300. The transmitter complies with EMC directive 2014/30/EU per EN 61326 Industrial and NAMUR NE-21, including surge and transient testing, and newly shipped units carry a QR asset tag.

What to confirm before ordering

• Sensor model and size, and integral or remote mounting (some sensors are remote only)
• Whether the second channel (Channel B) license and its separate power supply are needed
• Housing material and conduit thread (1/2 in NPT or M20)
• Hazardous area approval and the loop barrier, if any
• Applications required, such as API correction or concentration

Key features of the 4200 2-wire transmitter

• Loop power: the transmitter and the Coriolis sensor are powered entirely from the primary 4–20 mA loop, so no separate mains supply is needed in the field.
• Direct mass flow: as a Coriolis meter, it measures mass flow and density directly, without separate temperature and pressure compensation for liquids.
• Safety rating: certification for SIL2 and SIL3 per IEC 61508 makes it usable in safety instrumented functions within the limits of the safety manual.
• Smart Meter Verification: the basic pass/fail check confirms the sensor’s structural integrity in-line, without removing the meter from the process.
• Rugged housings: NEMA 4X, IP66/67/69K enclosures in painted aluminium or 316L stainless steel.

Using the 4200 in Oman’s oil, gas and process plants

Many existing plants in Oman and the GCC were wired for 2-wire instruments such as differential pressure flow transmitters or vortex meters. When an operator wants better accuracy or direct mass and density data on such a point, the main barrier is often the cost of new power cabling through classified areas. The 4200 removes that barrier by using the existing loop. Typical uses include chemical injection skids, custody-related allocation checks, fuel and condensate lines, and mass balance points in refineries and petrochemical units.

Environmental conditions also need attention. The aluminium housing is rated to 65 °C ambient and the stainless steel housing to 60 °C. Transmitters installed in direct desert sun can see surface temperatures well above the air temperature, so a sun shade is recommended for exposed locations. For offshore and coastal plants with salt-laden air, the 316L stainless steel housing gives better long-term corrosion resistance than painted aluminium. Use correctly rated cable glands and keep the conduit entries sealed to preserve the IP rating against dust and humidity.

Loop design checks

1. Confirm the power supply provides at least 17.8 V DC at the transmitter terminals with the full loop load connected.
2. Keep total loop resistance within the 600 ohm maximum load, and within 250 to 600 ohm when HART communication is used.
3. Include the voltage drop of any intrinsic safety barrier or isolator in the calculation.
4. If Channel B is ordered, provide its separate 7 to 30 V DC supply.

Commissioning and maintenance

Mount the sensor according to Micro Motion’s orientation guidance so that liquid lines stay full and gas lines do not trap liquid. Perform a zero under no-flow conditions at process temperature and pressure if the installation requires it, configure the measurement units and range via HART, and run Smart Meter Verification periodically to document meter health between calibrations.

Documents and quotation

The Micro Motion 4200 2-wire transmitter datasheet (PS-002153 Rev H, July 2024) is available from the product documents on this page. Seven Star LLC is an independent supplier in Muscat; send the complete order code from the nameplate or your specification and we will check it against the manufacturer documentation before quoting. Browse more flowmeters in the catalogue.