Electrical Installation in Hazardous Area

I don't see that. Basically you have two rated enclosures connected by conduit in the same hazardous rated atmosphere, unless we are missing something here about the second box. What is in the Ex-e box besides terminals?

I am not in the NEC area, but if this were Ex(d), there would need to be an Ex(d) gland or seal out of the EX(d) box & Ex(e) or equiv. into Ex(e) box. I would worry about wires in flex conduit between, since Ex(d) normally has solid conduit or armoured cable. Maybe it is an armoured cable between, flex conduit extra mechanical protection....

Thank you for your insight, I don't think so because the flex conduit was terminated using fit up connector in to the Ex-d box.

What type of hazardous area?

NEC 501.15 goes into various details depending on which hazardous environment the junction resides in. Also, those details cannot be seen in that image.

"

Gland for Ex d Equipment

Flameproof (Ex d) equipment introduces other considerations into the selection of glands:

Indirect Entry Methods

If the enclosure is indirect entry with an Ex e terminal chamber, then the glands can be single certified Ex e or Ex d/Ex e dual certified types.

If the enclosure is indirect entry with an Ex d terminal chamber, then the glands can be certified EX d, or Ex d/Ex e dual certified types. Ex d barrier type would be over-specified.

Direct Entry Methods

If the Ex d enclosure is direct entry, then the cable glands must be certified Ex d type, selected according to the version of IEC60079-14 applicable to the particular project.

According to IEC60079-15:2007

Select glands by using the flowchart for selection of cable gland for direct entry into a flameproof enclosure shown in the Figure 1.

If MICC cable is use must be fit with a suitable flameproof cable entry device. (i.e. Ex d MMIC gland)

The flowchart applies if thermoplastic, thermosetting or elastomeric cable is use. The cable must be compact, circular and effectively filled, with extruded bedding. Any filler must be non-hygroscopic."

https://bh-estore.com/cable_glands

What is the designation of the area that you show in your photograph? Until you state that or find out, then all of the suggestions are "best guess"!

it is class 1 div 1 area

Flexible connections are permissible if suitable materials are used. From the picture I can only say that the flexible conduit is grey.

The transit between the interior of the Ex d equipment and anywhere else has to comply with the flame path criteria, and so will need to be selected and installed likewise, even if the transiting cable is heading for an Ex e junction box.

The nature of the hazardous area is not significant as neither method of protection can be used in what in Europe would be called Zone 0.

<...still waiting response...> That's what happens when one doesn't do this: .

Just carry on waiting, then; why not (rhetorical question - NNTR)?

Hi there. BY "Hazardous" area you mean the ambient atmosphere contains explosive gases? What is the system voltage of the probes? If in a hazardous area, your instrumentation should be labelled by the manufacturer as intrinsically safe, as say, it has a IP72 grade or you may refer to UK COMAH (Control of Major Accident Hazards) Regulation of 2015.

Meanwhile, please examine if your probes will not chemically react with the ambient hazardous air, the electrical sockets are encased in explosion proof junction boxes and the cables are fitted with glands, so as to insulate the terminals.

Someone has accepted it. All you have to do is find the commissioning record documentation and read it, Mildred, and then you'd know who is was.

Is the hazardous area acceptable for the equipment (rhetorical question - NNTR)?

• If the hazardous area is too large or too persistent then the facility has a serious process materials containment problem to address, and faces the risk of prosecution - particularly if personnel are in Zone 1.