Ex 16A wall-mounted sockets

Mechanical lock for plugs in Ex sockets

---

What challenges does the client face?

Pulling the plug out of the socket whilst electricity is flowing may cause an electric arc. If flammable gases, vapours or dust are present in the vicinity, such an arc may cause ignition.

Application of the solution

The HSP1P 16 W-SCT sockets feature a mechanical lock, which prevents the plug from being removed whilst the circuit is live.

• inserting the plug into the socket,
• Turning the plug triggers the internal circuit breaker,
• in the operating position, the plug is locked in place,
• The release occurs upon returning to the off position.

What are the benefits for the user?

• a lower probability of disconnection under load,
• protection against dangerous electric arcs,
• the prescribed, correct sequence of steps,
• minimal wear on the contacts,
• greater comfort and safety at work.

Built-in circuit breaker in Ex-rated industrial sockets

---

What challenges does the client face?

In typical set-ups, the plug pins may make contact with the socket whilst the circuit is live. The operator cannot then be certain whether current is flowing whilst inserting or removing the plug.

The solution adopted

The HSP1P 16 W-SCT sockets are fitted with a switch integrated with a locking mechanism.

It is the rotation of the plug that triggers the circuit – simply inserting it into the socket does not close the circuit. It is the position of the plug that determines whether the socket is active and whether the plug can be removed.

What are the benefits for the user?

• fully controlled power supply activation,
• no need to fit an additional switch,
• intuitive operation,
• fewer live-line operations.

The presence of a circuit breaker in the socket does not eliminate the need for appropriate installation protection – the circuit still requires short-circuit and overload protection.

Protection against the plug being pulled out whilst under load

---

What challenges does the client face?

Sometimes, an operator may attempt to disconnect the device without first switching off the power supply. This results in accelerated wear of the contacts, arcing and an increased risk of ignition in an explosive atmosphere.

The solution adopted

In HSP1P 16 W-SCT sockets, the ability to remove the plug is mechanically dependent on the switch’s position.

The plug may only be removed after the circuit has first been switched off.

What are the benefits for the user?

The level of safety here does not depend solely on the operator’s vigilance – the very design of the socket prevents such a risky operation from being carried out.

Connecting electrical equipment safely in an Ex zone – step by step

---

---

Universal sockets for areas containing gases and dust

---

What challenges does the client face?

Areas at risk of gas explosions and areas with a dust hazard may co-exist within a plant. Maintaining separate systems of equipment complicates both the design and subsequent operation of the installation.

The solution adopted

HSP1P 16 W-SCT sockets are suitable for use in:

• Zones 1 and 2 – gases, vapours, mists,
• Zones 21 and 22 – combustible dusts and fibres.

Explosion-proof designation:

• II 2G Ex db eb IIC T5 Gb,
• II 2D Ex tb IIIC T80°C Db.

Variants are available for gases in Groups IIA, IIB and IIC, and for dusts in Groups IIIA, IIIB and IIIC.

What are the benefits for the user?

• a single standard for fittings throughout the entire building,
• simpler spare parts logistics,
• fewer different plug-in systems to manage,
• easier implementation of maintenance services.

Solutions for the chemical and refining industries

---

What challenges does the client face?

Chemical plants, petrochemical plants and refineries are environments in which electrical equipment must cope simultaneously with explosive atmospheres, moisture, corrosive vapours, temperature fluctuations and heavy-duty use.

The solution adopted

The HSP1P 16******W-SCT sockets offer the following connection:

• explosion-proof design for gases and dusts,
• housings made of glass-fibre-reinforced antistatic BMC,
• IP66 protection rating,
• ageing- and temperature-resistant silicone seals,
• mechanical plug lock,
• integrated circuit breaker,
• a wide range of operating temperatures.

Where it works well

• power supply for service equipment,
• maintenance bays,
• technological equipment,
• pumps and agitators,
• heaters,
• measuring equipment,
• auxiliary systems,
• parking facilities.

ATEX sockets for mobile and service equipment

---

What challenges does the client face?

Portable equipment is connected and disconnected repeatedly, which increases the risk of operator error, accelerated wear and tear on the contacts, and accidental disconnection whilst in use.

The solution adopted

The HSP1P 16 W-SCT sockets provide a safe power supply for compatible mobile devices in Ex zones.

Mechanical lock:

• maintains a stable connection,
• prevents the plug from being pulled out accidentally,
• forces the circuit to be switched off before disconnection,
• reduces the risk of an electric arc forming.

The self-cleaning design of the contact sleeves removes some of the contaminants every time a connection is made.

Typical applications include power supply for:

• mobile pumps,
• fans,
• measuring equipment,
• renovation tools,
• Ex-rated units and process equipment,
• portable service equipment.

16 A explosion-proof sockets – available variants

---

Below is an overview of the HSP1P 16 W-SCT socket variants with a rated current of 16 A.

Contact options

• 2P,
• 3P – 2P + PE,
• 3P – 1P + N + PE,
• 4P – 3P + PE,
• 4P – 3P + PE + NO,
• 5P – 3P + N + PE,
• 5P – 3P + N + PE + NO.

An additional NO contact can be used for signalling, control or monitoring the connection status – depending on the version.

Versions are available for AC voltages up to 690 V AC and DC voltages up to 250 V DC.

Protection against incorrect connection

---

What challenges does the client face?

Sockets with different voltages, currents and purposes may be installed in the same building. A mistake when connecting them may result in damage to the appliance or pose a hazard.

The solution adopted

The HSP1P 16 W-SCT system is based on several independent safety mechanisms.

Colour-coding of voltages

The colour-coding of the socket and plug components allows the voltage range to be identified quickly, thereby reducing the risk of incorrect connection.

Colour is only a guide – the rated data must always be verified separately.

Protection against the combination of different rated currents

A plug designed for a different current rating will not physically fit into a socket of a different design.

Protection against the use of non-Ex plugs

The design of the socket prevents the connection of a standard industrial plug that does not meet Ex requirements.

What are the benefits for the user?

• a lower risk of voltage error,
• the physical impossibility of connecting components with incompatible current ratings,
• protection against standard industrial equipment,
• easier identification of circuits.

Selecting an explosion-proof socket for a plug

---

The starting point is always to determine the specifications of the device to be powered.

1. Rated current

It must comply with the circuit specifications and those of the connected load.

2. Voltage

Check the device’s rated voltage and colour coding – the colour does not exempt you from checking the rating plate.

3. Number and arrangement of contacts

Determine whether the following are required:

• two contacts,
• two terminals and PE,
• phase, neutral and PE,
• three phases and PE,
• three phases, neutral and PE,
• an additional NO contact.

4. Type of Ex zone

The marking must comply with the classification of the location, the gas/dust group and the temperature class.

5. Ambient temperature

The maximum permissible value depends on the variant, the cable cross-section and the temperature class.

6. Cable

Please note:

• core cross-section,
• outer diameter,
• the number of cores,
• temperature resistance of the insulation,
• type of gland,
• the need to use armoured cable.

7. Customer service

The connection is made by turning the plug.

IP66 – protection for outdoor use

---

What challenges does the client face?

Outdoor equipment is exposed to rain, snow, dust, damp, condensation and temperature fluctuations.

The solution adopted

The IP66 protection rating of the HSP1P 16 W-SCT sockets protects the interior from dust and powerful jets of water.

Silicone seals can withstand:

• low temperatures,
• high temperature,
• ageing processes,
• changeable weather conditions.

Once the plug has been disconnected, the socket must be covered with a cap. The effectiveness of the protection also depends on the correct fitting of the cable glands and plugs.

What are the benefits for the user?

• installation outside buildings,
• protection against water and dust,
• less impact of the weather on the contacts,
• limited risk of moisture ingress.

IP66 does not imply resistance to immersion or to water being deliberately directed at an open socket.

Resistance to corrosion and low temperatures

---

What challenges does the client face?

Outdoor, marine, chemical and process installations expose equipment to low temperatures, moisture and corrosion.

The solution adopted

The housing, made from glass-fibre-reinforced antistatic BMC, ensures:

• corrosion resistance typical of the metal,
• high mechanical strength,
• thermal stability,
• good insulation,
• suitability for use in harsh industrial environments.

Operating range: from -45°C to +60°C.

What are the benefits for the user?

• work on outdoor installations,
• suitability for a cool climate,
• fewer problems with corrosion of the housing,
• a longer service life in harsh environments.

Self-cleaning contact sleeves

---

What challenges does the client face?

Contamination at the contacts increases the resistance of the connection, causes overheating and reduces the reliability of the power supply.

The solution adopted

The moving parts of the contact sleeves clean the contact surfaces every time the plug is connected.

What are the benefits for the user?

• a more stable connection,
• less build-up on the contacts,
• a lower risk of developing resistance,
• greater reliability with frequent use.

This feature is not a substitute for regular technical inspections

Two cable entry points to make installation easier

---

HSP1P 16 W-SCT sockets may have two threaded holes:

• 2 × M20 or 2 × M25

This makes it easier to choose the route for the cables and allows for through-wiring. Unused openings are sealed with certified Ex plugs.