How often should I maintain my high voltage equipment?

Maintenance of high voltage switchgear and transformers should follow the manufacturer’s recommendations as a minimum, should your business be dependant on safe security of electricity supply, we would be happy to assist you in building a cost effective maintenance strategy that works for you.

Following maintenance of our equipment what certification would we receive, would this satisfy the HSE should an incident occur?

All equipment maintained by HV Services would have an individual written report on its condition detailing further actions and remedial work to bring it back to serviceable condition. A copy record of maintenance works will be held on the HV database for 5 years. This would fully satisfy the HSE.

Are HV involved in renewable energy?

HV staff have been involved in the construction of over 30 renewable energy sites in the UK and Ireland, we are currently involved in eight renewable energy projects in England and Wales.

Can HV act as duty holder for my High Voltage network or advise me of our legal obligations under MHSW regulations.

HV offer a comprehensive operation and maintenance package, we can offer bespoke contracts of operation and maintenance, which can cover all your needs, as each high voltage installation and needs of the customer are different, we will work with you to establish the best way of managing your network for you.

What services to HV provide?

We provide amongst other the following popular services:- Pressure testing, VLF testing, Protection testing, Dissolved gas analysis, DGA, Oil sampling, Transformer oil sampling, High voltage cable jointing, 11KV jointing, Pfisterer terminations, Euromold termination, Lovink cable jointing, Reychem terminations, Circuit breaker maintenance, Oil switch maintenance, High Voltage cable fault location, Low Voltage cable fault location, Earth resistivity testing, Supply and Installation of transformers, Installation of 11KV switchgear, Design of 11KV substations, Design of 33KV substation, Windfarm electrical maintenance, High voltage servicing, Power factor correction surveys, Provide Senior Authorised Person, Switching and issue of Permit to work, Asset inspections.

What level of training do your operatives hold?

Our SAPs are all DNO trained and have held operational Authorisation with a number of DNOs as well as private network Authorisation.

Our jointing teams and fitting teams are DNO trained and have held various authorisations with a number of DNOs.

Can HV maintain sulpha hexafluoride (SF6) insulated equipment?

SF6 gas is has largely replace oil insulated switchgear. SF6 is a halon gas with excellent insulation and arc extinguishing properties. SF6 cannot be released to the atmosphere as it is classed as a greenhouse gas.

Can HV commission switchgear and transformers?

Yes, we can. We have the capability to fully commission most 11kV switchgear to manufacturer’s recommendations or to an alternative DNO specification. We have completed an extensive number of projects for customers across the UK, including SPPD (Scottish Power, Power Networks) and Northern Powergrid.

Do HV offer Thermographic Survey?

Yes, we carry out thermographic surveys of plant and equipment and distribution networks.

Do HV offer Partial Discharge Surveys?

Yes, we carry out partial discharge surveys of cable boxes, switchgear, busbar chambers and feeder chambers. The equipment we use is the EA technology, Ultrateve which provides an acoustic and current based reading in db, highlighting leakage in switchgear and cable accessories. An ideal non-intrusive preventative maintenance operation.

How does HV react to an emergency breakdown or fault if I call with an enquiry?

As part of our integrated HV maintenance package, we provide our customers with direct access to our network teams of highly skilled engineers and technicians who will respond in accordance with the contract agreement.

How can HV help me reduce my energy consumption?

HV would be happy to survey and help you optimise your HV network for low energy consumption.

How does the recent European eco-design directive on transformer loses affect my distribution network and business?

New design eco transformers manufactured since July 2015 are approximately 40-60% more efficient than previous designs, dating back prior to 1975. A cost verses reliability assessment should take into account the annual losses a pre 1975 transformer would cost. An example being a 1000 kVA fully loaded 1970 design could cost up to £7,000 per annum in copper and iron losses, compared to a similar eco transformer that could realise an approximate saving of up to £3,500 per annum.