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Addressing the challenges of power cabling
By Allan Russell, Technical Services Manager, 3M
Installers and contractors face a wide array of challenges that can make installation of
power cabling systems problematic, costly and time-consuming. Fortunately, there
are ways to address these issues, helping to reduce potential problems at a later date,
such as failed joints leading to power outages.
Whether involving low, medium or even high voltages, the challenges facing
installers and contractors in the electrical market are fairly universal. Challenges
include:
Different types of cable - in the past century or so, a variety of different cables have
been installed, meaning that contractors and installers have to deal with different
types, some that they do not recognise and are not aware of until they start the work.
Specifications from commercial customers may vary widely - some customers
accept British Standards such as BS7888, while others may require adherence to
Cenelec Standards. Some organisations may even have their own internal standards.
Customers may also have very exact requirements – relating to cable joints, joints
and installation techniques. Again, this places the onus on the contractor and its
installers to have very varied skills and experience. The growing trend towards
smaller core sizes means that kit selections are changing all the time.
The trend away from resins – due to increasing environmental pressure.
Cable abandonment – the need to decommission obsolete cables is increasing, but it
can be a complex process.
How can these challenges be solved:
Training - while utilities and some of the larger contractors have the means to initiate
formal training programmes, the vast majority do not have this advantage. Yet as the
market becomes increasingly complex, regular re-training is needed more than ever
before, in order to prevent poor installation techniques that can lead to power outages
at a later date. 3M runs its own training courses for installers.
Using new techniques – the right products can make installation more
straightforward. In medium voltage environments, 3M Cold Shrink joints and
terminations – which are used to ‘shrink’ joint splice bodies and terminations on to
the cable in a water and air-tight fit – have become the preferred method for creating
cable joints and terminations. No resins are used and Cold Shrink can also be used
for cable abandonment.
The installer is presented with a one piece accessory, comprising everything required
to carry out the joint or termination. As a result, joints and terminations are installed
more consistently and accurately, leading to fewer failures and power outages in the
future.
Clearly, while cable and jointing creates a range of issues for installers, contractors
and utilities to overcome, there are ways in which these can be surmounted, using the
right knowledge and products.