8/18/2019 2012 45 Winter Wiring Matters Marinas and Jetties

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MARINAS AND JETTIES

We review the requirements for electrical

installations in marinas, examining the

risks associated and future European-level

developments for inland navigation vessels

SECTION 709 of BS 7671 containsrequirements for marinas and similarlocations. This is based on EuropeanCENELEC Harmonisation Document HD60364-7-709.

Most, if not all, of the measures usedto reduce the risks in marinas may

equally apply to electrical shoreconnections for inland navigation vessels using the network of navigablerivers and canals throughout Europe, for which CEN is developing a standard.

One of the major differences betweensupplies to small craft in a typicalmarina and those required for electricalshore connections for European inlandnavigation vessels is the size of thesupply which may be required. Forexample, seagoing vessels accessingriver navigations can be up to 10,000gross tonnes and motor barges and tugsused on inland waterways in Europe are

considerably larger than the averagesize of vessel berthed in marinas; theseare generally recreational craft (up to24m length) or work boats and smallcommercial vessels and fishing boats.

Generally socket outlets with a ratingof 16A will be provided for each craft in

a marina. The risks associated withelectrical installations in marinas, suchas the presence of water, movement ofstructures and harsh environmentalconditions, are the same as for electricalshore connections for larger inlandnavigation vessels.

In this article we summarise some ofthe existing key requirements forelectrical installations in marinas andsimilar locations. The CEN requirementsfor electrical shore connections forlarger inland navigation vessels areexpected to be very similar to those inCENELEC HD 60364-7-709 and there isa joint working group set up to addressconvergence of the requirements.

Protection against electric shockThe protective measures of obstacles,placing out of reach, non-conductinglocation and protection by earth-free

local equipotential bonding, are notpermitted in section 709 (of BS 7671) formarinas. These measures are containedin Sections 417 and 418 of BS 7671:2008,and are not for general application. Theprotective measures of section 417provide basic protection only, and are

for application in installations controlledor supervised by skilled or instructedpersons. The fault protective provisionsof Section 418 are special and, again,subject to control and effectivesupervision by skilled or instructedpersons.

SuppliesRegulation 709.313.1.2 states that thenominal supply voltage of the installationfor the supply to small vessels,recreational crafts or houseboats shall be230V a.c. single-phase, or 400V a.c.three-phase. It is important to note that where the supply system is protectivemultiple-earthed (PME), Regulation 9(4)of the Electricity Safety, Quality andContinuity Regulations 2002 prohibitsthe connection of a combined neutraland protective conductor to anymetalwork of a caravan or boat.

Operational conditions andenvironmental factorsElectrical equipment to be installed onor above jetties, wharves, piers orpontoons must be selected according tothe external influences that may be > 

WiringFeature #45

By Geoff Cronshaw

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8/18/2019 2012 45 Winter Wiring Matters Marinas and Jetties

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