Rheonik RHE42 All-Digital Field Mount Mass Flow Transmitter

Fast, fully digital measurement electronics

The Rheonik RHE42 is an all-digital field mount transmitter for filling and batching, robot-mounted measurement, mixing and blending, polyurethane and paint dosing, oil and gas, and compact OEM or skid installations. Rheonik also cites high pressure, low flow chemical injection with sensors up to 1400 bar (20000 psi) among its uses. The transmitter measures mass flow, volumetric flow, density and temperature simultaneously and connects to any Rheonik Coriolis sensor.

A real time clock with battery and 1 GB of memory are on board, so data can be collected for later off-line analysis.

Feature highlights

• Signal processing for 0.05% accuracy on flow measurement over the entire range.
• 4 kHz update rate in the patented Fast Response software version.
• Eight totalizers: two non-resettable and six for mass or volume in positive, negative and net flow.
• Connectivity through USB, Modbus RTU, Modbus TCP/IPv4, HART, Profibus PA and FOUNDATION Fieldbus H1.
• License-free RHECom software and an optional RHEComPro+ suite with a training simulator.

Technical specification

Compact or remote mounting

Compact transmitters can sit directly on RHM06S to RHM20S sensors with sealless construction and N1, NA or E2 process temperature ratings. The permitted process temperature falls as ambient temperature rises; the datasheet charts show different limits for N1/NA and E2 ratings, and for ATEX/IECEx versus non-ATEX installations. For other sensors, the RHE42 must be mounted remotely.

I/O configurations and housing codes

Housing codes include RB and RC (remote, no display, 3 m or 10 m cable), RD and RE (remote with colour display), RF and RG (armoured cable), and C1 and CD (compact mount without or with display). I/O codes include B1 (two digital outputs, two inputs and Modbus), EB (adds Modbus TCP), EA (two analog outputs, Modbus TCP and HART), S1, 1H, S2, i1 and i2 (intrinsically safe), FF and F2 (FOUNDATION Fieldbus) and PA and P2 (Profibus PA). Software packages are SO, DO, AF, OG, CT and FR.

Software and network flexibility

Packages build in steps: SO (standard), DO (measured density), AF (Assurance Factor, data recording, PID controller), OG (API standard density, Net Oil, concentration), CT (Precision Flow Analysis and hardware lock switch) and FR (4 kHz Super Fast Response firmware). Rheonik describes an AnyInterface Commitment under which RHE 40 series transmitters can connect to HART, Profibus DP, ProfiNet, EtherCAT, PowerLink, EtherNet/IP, CAN and other networks. The RHEComPro+ suite adds extended diagnostics and a simulator that mimics the front panel for training.

Typical Gulf applications

Dosing skids for polymers and resins, injection of corrosion inhibitors at high pressure, and filling lines where fast response matters. Fieldbus options match plant networks that are standardised on Profibus PA or FOUNDATION Fieldbus.

Choosing between the RHE42 and other models

Pick the RHE42 when you need fieldbus connections such as Profibus PA or FOUNDATION Fieldbus, a 4 kHz update rate, or a transmitter mounted directly on a small sealless sensor. The datasheet lists hazardous area approval for ATEX/IECEx Zone 1, 2 and CSA Class I Div. 1, 2, with the sensor and transmitter approvals required to match. The housing is coated aluminum rated IP65 or IP66 depending on the code. Where a stainless steel Ex d case or AC supply is required, the RHE21 is the corresponding model.

The datasheet title for this model is Field Mount All-digital, and its housing codes list aluminum Exd(e) cases rated IP65 with 3 m or 10 m integral cables, with or without a colour display. Check the housing code against the area classification of your site and the approval of the sensor it will serve.

Selection and installation notes

A mass flow transmitter must match the sensor it is connected to, so confirm the sensor model, the cable length, the supply voltage, the output types and the area classification before ordering. Keep the signal cable away from power cables, ground the shield as described in the manual, protect the housing from direct heat and water ingress and record the calibration factors and zero values at commissioning. Use the correct cable glands and seals, particularly in hazardous areas.

Information needed for a quotation

Send the full model code, the quantity, the delivery location in Oman or the GCC, the intended use and any accessories needed, so that the complete package can be quoted together.

Documents and supply information

The manufacturer data sheet is attached to this page and should be read together with the project specification and the site risk assessment before a purchase is confirmed. Ratings, standards and dimensions are quoted as printed on that sheet. Lead time, stock position and certificates available with the shipment are confirmed in the quotation, and we supply to Oman and the wider GCC region for industrial, utility and building services projects.

Related items

Pair it with RHM Coriolis sensors; see flow and process measurement for related equipment. The datasheet title is Field Mount All-digital; Rheonik’s product page names the variant as Ex de, so confirm the exact approval code. Send your sensor and fieldbus needs for a quotation.