Cable connectors
Reductions / reducers Cable connectors
What are reducers or reductions?
Cable entries are used in various areas, for example in the form of cable glands. Cable glands are usually found in control cabinets but also in other places where cables need to be fixed and sealed. Cable glands are differentiated into connectors with a metric or PG thread. For the latter, what is known as a steel conduit thread is used.
If cable glands with different nominal diameters are used, reducers or reductions, such as those offered by the manufacturers LAPP and Wiska, provide the required connection. Reducers are available in different materials and can have different designs. A hexagonal design or the round variant is typical here.
What is a reducer used for?
Reducers are used when the connection thread of a cable gland is smaller than the threaded hole of a device. Consequently, devices and cable glands that have different threads can also show compatibility with reducers. Their use is conceivable in all electrical areas.
Whether they are in a control cabinet, data cable or machine - when cable glands are used, it is always a possibility that the corresponding device contains a different thread. Reducers then provide a remedy and enable a connection between the cable gland and the device.
What materials do reducers consist of?
Like cable glands, reducers are also available in different materials. The most common material is polyamide, or PA for short, which is characterised by its high resistance and dimensional stability. Reducers made of polyamide can also be reinforced with glass fibre, which further enhances their mechanical stability. In addition, PA can be recycled.
But brass is also impressive with its high degree of stability and it is also corrosion-resistant. Furthermore, nickel plating of brass provides even higher corrosion resistance, even in very wide temperature ranges. Reductions that comply with the ATEX directives can also be used in an explosive environment.
When is which material used?
Both reducers made of polyamide and nickel-plated brass are used in housings as well as a variety of devices and machines, for example in the automotive industry or in food technology. In principle, reductions can be used wherever cable glands can be found - i.e. wherever it is necessary to pass cables through them.
When selecting the right reduction, for one thing the correct dimensions play a role. The size of the thread for which the reduction is required and the thread size of the reducer itself must be taken into account.
The type of thread and the temperature range also play a key role. For areas where particularly high mechanical stability is required, using glass fibre reinforcement is wise. This is the case, for example, when components are exposed to strong vibrations. In addition, some environments require IP protection certification, for example, to enable cable glands to be used in particularly dusty or damp conditions.
Overview of materials for connectors
| Type according to material | Application | Advantage/Disadvantage |
| Plastic cable gland | Distribution boxes, control cabinets, photovoltaics | Cheap and lightweight / not electrically conductive |
| Stainless steel cable gland | Hygiene area, shipbuilding, ATEX / Ex-EMC | Corrosion-resistant/ high weight, comparatively expensive |
| Metal cable gland | Plant, vehicle and machine construction | robust, temperature-resistant / high weight |
| Brass cable gland | Shipbuilding, ATEX /Ex-EMC | temperature-resistant / high weight, comparatively expensive |
What types of threads exist in reducers?
Reducers come with both metric thread and steel conduit thread (PG). Metric cable glands and reducers are accompanied by a standardised thread whose nominal size is titled with an M. This is followed by a number which specifies the outer diameter. The following sizes are typical and can be found in our shop:
- M12
- M16
- M20
- M25
- M40
- M50
Cable glands or reducers with steel conduit thread on the other hand are marked PG. However, PG cable glands are not used very often nowadays.
Overview of metric threads for cable glands
| Nominal size metric | Clamping range (approx. data) | Outer Ø of thread in mm | Pitch |
| Cable gland M12 | 3 - 7 mm | 12.0 | 1.5 |
| Cable gland M16 | 4.5 - 10 mm | 16.0 | 1.5 |
| Cable gland M20 | 7 - 13 mm | 20.0 | 1.5 |
| Cable gland M25 | 9 - 17 mm | 25.0 | 1.5 |
| Cable gland M32 | 11 - 21 mm | 32.0 | 1.5 |
| Cable gland M40 | 19 - 28 mm | 40.0 | 1.5 |
| Cable gland M50 | 27 - 35 mm | 50.0 | 1.5 |
| Cable gland M63 | 34 - 45 mm | 63.0 | 1.5 |
M Thread according to EN 60423 or IEC 423 or BS 6053 ISO 68/DIN13
Overview of PG threads for cable glands
| Nominal size PG | Clamping range (approx. data) | Outer Ø of thread in mm | Pitch |
| Cable gland PG7 | 2 - 6.5 mm | 12.5 | 1.27 |
| Cable gland PG9 | 4 - 8 mm | 15.2 | 1.41 |
| Cable gland PG11 | 4 - 10 mm | 18.6 | 1.41 |
| Cable gland PG 13.5 | 5 - 12 mm | 20.4 | 1.41 |
| Cable gland PG16 | 8 - 14 mm | 22. 5 | 1.41 |
| Cable gland PG21 | 11 - 18 mm | 28.3 | 1.588 |
| Cable gland PG29 | 16 - 25 mm | 37.0 | 1.588 |
| Cable gland PG36 | 19 - 32 mm | 47.0 | 1.588 |
| Cable gland PG42 | 28 - 38 mm | 54.0 | 1.588 |
| Cable gland PG48 | 34 - 44 mm | 59.3 | 1.588 |
PG thread according to DIN 40430