Frequently Asked Questions
When installing in Increased Safety Exe applications, there is nothing in the standards that prevents the use of two adapters. However, we would not recommend the use of more than one adaptor as you are increasing the number of sealing faces and the length of the installation. Note that flameproof Exd applications only allow for a single adapter/reducer, in accordance with EN 60079-14 Clause 10.6.1.
Cable Glands - Applications
Hawke Exd cable glands have been tested and certified to temperatures of minus 80°C. The EN 60079 standards dictate the rigorous testing required to gain approvals for these temperatures.
Our cable glands are manufactured as standard from brass and we have been supplying our hazardous area cable glands for offshore applications for the last 50 years without complaint. So we would have no hesitation in recommending their use in this environment.
We have been supplying brass cable glands to the offshore industry for the last 50 years without complaint. We would have no hesitation in recommending their use in this environment.
Depending on the environmental conditions and the cable type the following industrial cable glands are suitable: If the cable is unarmoured and IP66 ingress protection is required then use the 121 or 123. If the cable is armoured with an outer sheath and inner extruded sheath and IP66 ingress protection is required on the outer sheath only then use the 151/RAC Cable Gland. If you require IP66 rating on inner sheath also then use the 153/RAC, the 153/UNIV or the 153/RAC/L Cable Gland for lead sheathed cable.
An alternative armour clamping ring (AR) is available on armoured/braided type cable glands sizes B to F. This ring enables the clamping of armour with dimensions that outside our standard RAC ring clamping range. Refer to the gland datasheet for further clarification.
Cable Glands - Installation
When mounting Hawke Cable Glands onto enclosures, using plain holes and locknuts, the recommended clearance on diameter is +0.2mm on nominal thread diameter. For example, M20 should be mounted into 20.2 diameter clearance holes. Maximum recommended clearance is +0.7mm diameter, which is stated on the certificates for Hawke Enclosures.
Cold flow occurs when cable (generally the inner sheath) is subjected to external forces created by the sealing rings on cable glands. The cold flow occurs when the forces created by the cable gland sealing ring are greater than the resistance to deformation offered by the cable sheath. Cables which are particularly susceptible are those with flame retardent and or flame resistant qualities. This is because the additives introduced in the base material of the extruded sheath tend to make them softer.
The amount of time it takes to install a cable gland is very dependent on the cable type and the gland type being installed. We have recently updated the gland product range to continue to continue to evolve the user experience and to accelerate installation time. We pride ourselves on ensuring that our glands are market leaders when it comes to installation time. In particular, the new Hawke Express resin drastically reduces barrier gland installation time when compared to the conventional epoxy putty.
Minimum hole spacing is dictated by the certification of the enclosure, not the cable gland. Having said that, the installer should consider the across corner dimension of the cable gland, which defines it's footprint and therefore minimum mounting centres. Consideration should also be given to accessories such as sealing washers, earth tags and shakeproof washers which have larger diameters that can restrict minimum mounting centres. Also consider the access to the enclosure which may restrict the space available to access the glands with a wrench.
If the cable gland has the required 5 full threads engaged then the installation would comply with the requirements of Exd However, it is not best practise to install in this manner. Hawke International recommend the gland is fully bottomed out on the entry flange.
When using unplated clamping components with aluminium armour, the possibility of galvanic corrosion is limited due to the small contact area and the fact that the cable gland will not allow moisture into the clamping area to allow it to act as an electrolyte. Having said that, we would recommend that the internal brass components are nickel plated to eradicate any risk of galvanic corrosion.
Grounding of the cable gland can be done in three ways:- 1. If the enclosure into which the cable gland is fitted is metallic and earthed then, provided the gland is in full contact with the enclosure, earthing of the gland will be achieved. 2. If the enclosure is plastic and contains a metallic grounded ECP plate, provided the gland locknut, and serrated washer (if required) are in full contact with the enclosure, earthing of the gland will be achieved. 3. If the enclosure is plastic, the installer can fit an earth tag between the cable gland and enclosure either internally (being aware of creepage and clearance requirements) or externally. A wire can then be taken from the earth tag to an internal or external grounding bar.
The use of sealing washers is not part of the product certification, it is covered in EN 60079-14: Electrical installations design, selection and erection. It is acceptable to fit sealing washers between flameproof enclosures and cable glands provided that the 5 full threads of engagement between the two components is maintained.
Cable Glands - Lead Sheath Cable
We would not generally recommend the use of "/L" cable glands with non lead sheath cable. There is a risk that the internal grounding clip will damage the inner sheath of the cable, particularly if it is soft bedded cable. Also note that the cable acceptance range is reduced when /L cable gland are used versus standard.
If the 501/453 RAC/L cable gland has been assembled in accordance with our assembly instructions then the lead sheath will protrude about 5 to 10 mm through the entry. If this is not the case and the extruded bedding under the lead inner sheath protrudes through the entry and the continuity device is in contact with the lead then this is also acceptable.
Cable Glands - Materials and Finish
The non-metallic components (e.g. Seals) used in Brass, Aluminium and Stainless Steel glands are identical. The only difference is in the materials used for the metallic components.
There is no ATEX/IECEx certification covering the corrosion resistance of cable glands. However, Hawke International unplated and plated cable glands have been used in aggressive and offshore environments for many years, and we can point to this experience to confirm suitability for use.
The 711 Cable Gland is manufactured as standard in Brass with a Nickel Plated entry portion. However, the gland is also available fully Nickel plated, in Stainless Steel or Aluminium on special request.
Cable Glands - Protection Concepts
The entry thread does form a flamepath between the enclosure and the cable gland. When installed with parrallel threads, there must be a minimum of five full threads engaged between the enclosure and gland as specified in EN 60079-1.
Cable gland selection will be dependent on cable type and application. All ATEX/IECEx Exd/Exe certified cable glands are also certified for use in Ext dust protection concepts. Our UL listed products are covered for Class 1, Class 2 and Class 3 applications. Refer to the product datasheets for further clarification.
Cable Glands - Threadforms
ET (Electrical Thread) is a dated English threadform defined in BS 31:1940. It has all but dissapeared as metric threadforms have all but replaced it. For applications requiring an ET Entry Thread, Hawke recommend the use of an Ex approved adaptor as this is a non standard threadform for Hawke products.
Hawke cable glands are offered with Metric and NPT entry threadforms as standard. Metric threadforms are generally 15mm long as standard and stated on the product datasheets. Extended metric thread lengths and alternative threadforms may also be available upon request, please contact us for more details.
Hawke metric entry & mounting threads are manufactured to 6g tolerance in accordance with BS 3643.
P.F. thread is a Korean/Japanese equivalent to our B.S.P.P. UNI – 6125-74 is an Italian equivalent to our B.S.P.T.
All cable glands that are metallic will provide EMC/RFI protection, as the body of the cable gland provides more robust protection than any screen. When selecting cable glands for screened cable, the installer should consider how the screen will be terminated, either inside the cable gland or inside the enclosure. We have had our cable glands independently tested to confirm their EMC/RFI protection capabilities and this test certificate can be supplied upon request.
Taper threaded holes in certified plastic enclosures are not permitted due to the bursting effect they have. We would even advise against this on an industrial plastic enclosure. Consider using a Metric/NPT Adaptor.
As per EN 60079-14, Clause 10.2 Note 2, threaded joints of minimum 6mm length, mounted perpendicular to the enclosure face, will achieve IP54 without additional sealing. If a higher IP rating is required, an additional suitable sealing method should be used, of which a sealing washer is one option. This applies to any joint including gland to enclosure, adaptor to enclosure and gland to adaptor. If the enclosure uses a plain hole as opposed to threaded, an appropriate sealing method should be used to achieve anything greater than IP42.
When enclosures or cable glands are tested, the IP ratings only apply to either the enclosure or cable gland - not to the joint between the gland and enclosure. It cannot be assumed that a combination of IP66 cable gland and IP66 enclosure will automatically provide an IP66 installation. The installer should ensure that the joint meets the IP requirements of the equipment and/or site by using suitable sealing methods where required.
In 2019, Hawke International discontinued our range of fibre sealing washers, and now offer only black nylon sealing washers. The black nylon washers also have a superior operating temperature window and will be used as a building block for future projects. Fibre washers have historically been supplied by Hawke used in offshore applications for many years and based on our experience are generally fit for purpose in these applications. Fibre washers may be limited in sub zero applications, as they absorb moisture and when this moisture freezes they can be susceptible to cracking.
Our cable glands are generally rated IP68 at 30 bar for 7 days. Refer to the datasheet for further clarification.
Shell DTS01 Deluge Protection
The external deluge boot provides deluge protection to the armour clamping section of the cable gland when the product is subjected to conditions detailed in the Shell DTS01 Deluge Test. It is also used as an gland type identifier. Typically, a black deluge boot indicates the gland is a 501/453/UNI, red boot indicates the gland contains a compound barrier and no boot indicated the gland contains a conventional compression seal.
The Shell DTS01 is a test designed to ensure that in when the offshore deluge fire suppression systems are employed, water does not enter the electrical enclosure. This test is not part of certification but is often desired and specified in offshore applications.
The majority of Hawke cable glands are compliant with DTS01. Where applicable it is stated on the product datasheets. Where the gland is supplied with an external deluge boot fitted, additional protection to the armour clamping area of the gland is maintained.