

Instruments for Hazardous Locations
Intek offers a line of flow meters and switches in a variety of configurations to meet the most demanding industry needs. Rheotherm instruments are commonly installed in hazardous (classified) areas through Factory Mutual (FM) approved integrated designs, FM-approved intrinsically safe barriers (ISB) to isolate the flow sensors, NEMA 7 enclosures, and purged enclosures.
Flow Meters for Hazardous Locations
The Model 210 Flow Meter is available with an FM-approved explosion-proof design for use in measuring both liquids and gases. In this configuration, the flow sensor is integrated with the flow meter electronics. The Rheotherm sensor is designed for operation in hazardous environments and the electronics is supplied in an explosion-proof NEMA 4X enclosure. The unit is available with or without an integrated LCD display and in both insertion probe and inline sensor configurations.
Rheotherm Flow Meters for hazardous locations are also available in a remote electronics configuration where the electronics can be remotely located from the sensor by up to 200 feet. The sensor is connected to the electronics through an ISB which provides the necessary isolation of the electrical components. It is also available with or without an LCD display and with both insertion probe and inline sensors. This configuration is often required where space is limited or when instrument options such as AC power and certain other types of outputs are desired.
Flow Switches for Hazardous Locations
Rheotherm Flow Switches can also be installed in hazardous areas using Intek’s proprietary, FM-approved intrinsically safe barrier. The sensor of the Model 100FS Flow Switch is installed in the hazardous location with the electronics and the ISB located either in a non-hazardous remote area, or within the hazardous area if installed in a NEMA 7 explosion-proof housing. A purged enclosure may also be used in areas which require maximum explosion protection.
Area Classifications for Rheotherm Instruments
FM – For US and Canada
Model 210 Flow Meters | ||
Integrated Electronics ▪ 210-X (no display) ▪ 210-XDT (local display) |
Explosion proof | Class I, Division 1, Groups B, C, and D Class II, Division 1, Groups E, F, and G Class III, Division 1 |
Remote Electronics ▪ 210R-I-ISB (no display) ▪ 210R-IDT-ISB (local display) |
Intrinsically safe* | Same as above, except Group A is included |
Model 100FS Flow Switches (US Only) | ||
Remote Electronics ▪ 100FS-I-ISB |
Intrinsically safe* | Class I, Division 1, Groups A, B, C, and D Class II, Division 1, Groups E, F, and G Class III, Division 1 |
ATEX and IEC
* Remote electronics supplied in NEMA 4 enclosure with Intrinsic Safety Barrier which must be located outside of hazardous area. Optional NEMA 7 enclosure available for electronics location within hazardous area
Model 210 Flow Meters | ||
Remote Electronics ▪ 210R-I-ISB (no display) ▪ 210R-IDT-ISB (local display) |
Intrinsically safe* | FM16ATEX0050X II 1 G Ex ia IIC T4 Ta = -40°C to +60°C |
Model 100FS Flow Switches | ||
Remote Electronics ▪ 100FS-I-ISB |
Intrinsically safe* | FM16ATEX0050X II 1 G Ex ia IIC T4 Ga = -40°C to +60°C |
Need Additional Information?
If you have additional questions regarding the use of Intek systems in hazardous locations, use the form on this page to submit your questions, or visit our contact us page for telephone, fax and email information.
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Options for Hazardous Locations (US & CA) |
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Hazardous Location Options (International) |
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FM Approval Documents for Model 210 |
Hazardous Environment Standards
Applicable to Intek Flow Meters and Switches
FM and ANSI – For US
Model 210 Flow Meters and Model 100FS Flow Switches | |
Title | Standard Number |
Electrical Equipment for Use in Hazardous (Classified) Locations – General Requirements |
FM Class 3600:2011 |
Intrinsically Safe Apparatus and Associated Apparatus for Use in Class I, II & III, Division I, Hazardous (Classified) Locations |
FM Class 3610:2010 |
Explosion Proof Electrical Equipment General Requirements | FM Class 3615:2006 |
Electrical Equipment for Measurement, Control and Laboratory Use |
FM Class 3810:2005 |
Enclosures For Electrical Equipment (1000 Volts Maximum) | ANSI/NEMA-250:2014 |
CSA – For Canada
Model 210 Flow Meters | |
Title | Standard Number |
Bonding and Grounding of Electrical Equipment (Protective Grounding) | CSA-C22.2 No. 0.4:1982 |
Threaded Conduit Entries | CSA-C22.2 No. 0.5:1982 |
Enclosures for Use in Class II Groups E, F, and G Hazardous Locations | CSA-C22.2 No. 25:1966 |
Explosion-Proof Enclosures for Use in Class I Hazardous Locations | CSA-C22.2 No. 30:1988 |
Special Purpose Enclosures; Industrial Products | CSA-C22.2 No. 94:1991 |
Process Control Equipment | CSA-C22.2 No. 142:1990 |
ATEX
Model 210 Flow Meters and Model 100FS Flow Switches | |
Title | Standard Number |
Electrical apparatus for explosive gas atmospheres. Part 0: General Requirements | EN 60079-0-2012 + A11:2013 |
Explosive atmospheres Part 11: Equipment protection by intrinsic safety “i” |
EN 60079-11:2012 |
Directive 2014/34/EU of the European Parliament and of the Council | Directive 2014/34/EU |
IEC (International Electrotechnical Commission)
Model 210 Flow Meters and Model 100FS Flow Switches | |
Title | Standard Number |
Electrical apparatus for explosive gas atmospheres. Part 0: General Requirements | EN 60079-0-2011 |
Explosive atmospheres Part 11: Equipment protection by intrinsic safety “i” | EN 60079-11:2012 |