• Designed to build up high-performance multipoint measuring systems easily
• May be combined with any flow transmitter of the COMBIMASS® series
• Highly precise flow rate measurement of gases even with short inlet and outlet pipe sections, large nominal diameters or rectangular ducts
• Redundant gas flow measurement for the purpose of safety precaution or economical control of critical processes
• Suitable for complex applications such as flow metering of mixed gases with variable composition
• Optional data loggers available for non-volatile recording of measured flow rates

THE SYSTEM

The COMBIMASS® multi module was designed to build up a high performance multipoint system for thermal flow rate measurement of gases. To each electronic module up to three flow transmitters of the COMBIMASS® series can be connected.

A COMBIMASS® multipoint system allows for thermal flow rate measurement of gases even with short inlet and outlet pipe sections, nominal diameters larger than DN 500 or rectangular ducts. In such situations flow profile distortions may occur, which normally lead to errors in flow metering of gases. By installing multiple measuring points over the cross-section of the pipe or duct and averaging the flow signals, COMBIMASS® multi enables accurate and reproducible results even in such demanding applications.

For applications, which are critical from a safety point of view or in such cases where faulted results may cause considerable costs due to uneconomical process control, COMBIMASS® multi enables redundant monitoring of gas flow rates. Permanent functionality checks of the connected sensors as well as continuous plausibility checking of the flow signals guarantee outstanding reliability of the system. In case of any inconsistency or if one of the connected sensors fails an alarm will be immediately released. In such case of malfunction, COMBIMASS® multi automatically considers only those signals of the working flow sensors for signal processing, thus largely avoiding erroneous measuring results. For indication of the measured flow rates or selected parameters as well as for programming of the multipoint system an optional graphic display with control pad is available. Two field selectable analog outputs and one impulse output are used for transmission of the flow or temperature signals. COMBIMASS® multi allows indication and checking of the actual reading of any of the connected flow transmitters in the field. For monitoring of flow rate or temperature limits up to three switch points can be field set by programming the relay outputs of the COMBIMASS® multi module. Via those relay outputs either an alarm may be released or any external device such as a valve or pump may be controlled. COMBIMASS® multi features processing of external control signals in order to run complex applications. In order to enable monitoring of those external control signals an analog input as well as a relay input are available. Optional COMBIMASS® multi can be upgraded with two independent data loggers. These allow for non-volatile recording of measured flow rates over free selectable time periods. Comfortable evaluation functions enable easy analysis of stored data. These data can also be transferred via an integrated RS 232 port to any computer for further archiving and evaluation.

APPLICATIONS

• Flow rate measurement of air or sterilized air in rectangular ducts, eg. in semiconductor industry, for dosing of drugs in pharmaceutical industry, in air conditioning
• Stack monitoring in power and incineration plants, cement industry and other industrial plants
• Combustion air and pre-heater air flow monitoring
• Flue and waste gas recirculation monitoring
• Gas flow monitoring through scrubbers and precipitators
• Redundant flow monitoring of process gases in critical applications
• Flow rate measurement of gas mixtures with variable composition in pipes with large nominal diameter or short inlet and outlet sections (eg. combustion gases, flare gases, process gases, …)