All You Need to Know About Switchgear – What Is It, How Does It Work and Types

The combination of circuit or fuses, electrical disconnects switches or breakers used to isolate, protect and control electrical equipment or gears from the defective condition are usually called switchgear.

Listed below are some examples of switchgear:

  • Fuses,
  • Switches
  • Relays
  • Isolator
  • Circuit Breaker
  • Potential and Current Transformer
  • Indicating Device
  • Lightning Arresters

Let us discuss what switchgear is, how does it work, and what are its types.

What Is Switchgear?

The switchgear systems are connected to the electric supply system.

It’s placed in both the low and high voltage of the power transformer. It’s used for de-energising the equipment for maintenance and testing to eradicate the defect. Each time ant defect or failure (for example, short circuit) takes place on the power system, a heavy current run through the electric equipment, enormous damage to the apparatus and disruption of supply to the user.

In the course of standard operation, switchgear allows the switch to on or off distributors, transmission lines, generators and some other electric powered equipment.

How Does Switchgear Work?

The automated protective switchgear primarily includes the circuit breaker and relay.

The relay comes into action when a fault occurs, and it usually closes the trip circuit which automatically disconnects the faulty line. After that, the operative and healthy section runs the normal and required supply load. And therefore, there’s no damage to apparatus and no disruption of supply.

While the occurrence of any fault or defect in the power system, all electric apparatuses are vulnerable to have a heavy current which means the apparatus could get damaged and the supply also gets disrupted.

Types of Switchgear

HV: High Voltage Switchgear

The power system controls voltage over 36KV, which is known as high voltage.

As the voltage is usually high, the arcing generated during transitioning operation is also high.

Therefore, additional care is taken during manufacturing of high voltage switchgear. A high voltage circuit breaker is actually the major part of HV switchgear, that’s why high voltage circuit breaker needs to have specific features for reliable and safe operations.

LV: Low Voltage Switchgear

In most cases switchgear which is rated up to 1 KV is usually called low voltage switchgear.

The term LV Switchgear consists of low voltage switches, earth leakage circuit breaker, HRC fuses, offload electrical isolators, moulded case circuit breakers (MCCB) and miniature circuit breakers (MCB).

MV: Medium Voltage Switchgear

From three KV to thirty-six KV switchgear systems are sorted as MV switchgear or medium voltage switchgear.

Most of these switchgears are of several types. They are usually metal enclosed outdoor type, metal enclosed indoor type, indoor or outdoor type without the metal enclosure, and so forth.

The interruption channel of this particular switchgear is a vacuum, SF and oil. The primary responsibility of the MV power system is to disrupt heavy current during defective situation no matter what type of CB is being used in the medium voltage switchgear system.

Wholesale Prices rocket again

Oil is up by 1.57% this morning, along with Gas Front Month offers up 3.019% this morning also.

Electricity Front Month offers closed yesterday at 54.57 £/MWh – its highest level since 06/12/2013.

We have already received notification of 2 supplier pricebooks being withdrawn today so please be aware that other suppliers may follow although we have received no definitive confirmation.


Wholesale Prices Soar – EVI-e hits 670%

Day ahead prices are high and rising fast.  today’s opening price is £179 MWh.

The price increase has been caused by a combination of weather – not as windy as expected – reducing generation and much hotter than expected in the South – increasing load for cooling, reduced nuclear generation in France and issues with the interconnector from UK to France means less power available from Europe.  We are currently very close running out of power, and any unexpected failure in the system would lead to blackouts or diesel generation being started up.

EVI-e – 669%

EVI-e Graph

UK Power Prices (£/MWh)
Price Period Previous Open Current Open Change
Day Ahead 54.00 179.41 125.41
Oct-16 40.90 46.88 5.98
Nov-16 45.30 49.44 4.14
Dec-16 47.24 46.42 -0.82
Q4 2016 43.96 46.35 2.39
Q1 2017 46.49 48.06 1.57
Winter ’16 44.97 46.66 1.69
Summer ’17 38.20 38.77 0.57
Winter ’17 42.62 42.89 0.27
Summer ’18 36.92 37.29 0.37
Winter ’18 40.85 41.26 0.41


Meaford Energy Limted Granted Development Consent Order For 299mwe Gas-Fired CCGT Power Station

Meaford Energy Limited, a 50/50 joint venture between St. Modwen Properties PLC, the UK’s leading regeneration specialist and Glenfinnan, a property investment company with expertise in infrastructure and energy projects, has secured a Development Consent Order (DCO) from the Rt. Hon. Greg Clark MP, the Secretary of State for Business, Energy and Industrial Strategy for a £300m combined-cycle gas turbine (CCGT) power station with a generating capacity of up to 299 MWe.

To be delivered on 14 acres of land currently owned by St. Modwen, the new power station, to be known as the Meaford Energy Centre (MEC), is a Nationally Significant Infrastructure Project, which secured a DCO after a thorough three-year process involving public consultation and examination by the Planning Inspectorate on behalf of the Government.

A third of the UK’s electricity output is produced by facilities which are due to close over the coming 10 years, however to meet increasing demand for power over the next 20 years, the Government predicts that an additional 50 GW of generating capacity is needed. CCGT power stations like the MEC use gas and steam to produce electricity flexibly and efficiently. Together with wind farms, solar parks and nuclear power stations, they form an important part of the new energy mix needed to meet the UK’s energy demands.

Daniel Chapman, Director of Meaford Energy Limited, said:

“To secure the DCO for this important national infrastructure project at Meaford is significant in terms of meeting the UK’s energy needs as set out in the National Energy Policy, as coal-fired power stations come offline and uncertainty increases over the delivery of new nuclear power plants”.

Rupert Wood, Director of Meaford Energy Limited and Regional Director for St. Modwen, said:

“Just as importantly, the MEC will also deliver the catalyst to progress the development of St. Modwen’s Meaford Business Park which already benefits from a planning permission to deliver 1m sq ft of employment space.

“Achieving this important milestone is further evidence of the joint venture partners’ deep expertise in successfully delivering highly complex planning consents. It also shows St. Modwen’s ability to identify innovative routes to market which create substantial long-term value for shareholders from our 6,000 acre land bank.

“Meaford Energy Limited will now focus on developing a plan of action that will deliver the project”.

As well as generating electricity, the power station will:

  • Provide 30 highly skilled permanent local jobs
  • Create up to 800 construction jobs over three years
  • Improve the area’s energy security, including providing an important source of energy to the planned Meaford Business Park.

“Great to see this kind of project going ahead post Brexit.  Hopefully the first of many” – Nick Grogan, Energy Solutions

Meaford Energy Limited –

Meaford Energy Limited is a 50/50 joint venture company between St. Modwen and Glenfinnan. St. Modwen’s extensive brownfield development and regeneration expertise, combined with Glenfinnan’s in depth and technical knowledge of the energy market, has created an ideal partnership; bringing together detailed planning and development experience with valuable technical knowledge to answer the increasing demand for alternative UK energy supplies in the most efficient way.

St. Modwen Properties PLC

 St. Modwen is the UK’s leading regeneration specialist. The company operates across the full spectrum of the property industry from a network of regional offices, a residential business and through joint ventures with public sector and industry leading partners.


The Company is focused wholly upon regeneration with an outstanding 30 year track record of adding value by managing schemes through the planning process, remediating brownfield land and active asset management and development.

 With extensive experience in dealing with complex and challenging sites, St. Modwen has a land bank of over 6,000 acres and is focused on the long-term development of commercial property and residential land.

St. Modwen’s £1.7bn national portfolio of over 100 projects includes; the regeneration of New Covent Garden Market, London; the transformation of Longbridge, Birmingham and the on-going regeneration of over 2,500 acres of former industrial land in South Wales which includes the delivery of the new £450m Bay Campus for Swansea University.


 Glenfinnan is a property investment company with a long history in bringing forward large regeneration and infrastructure projects.  These include:

Marchwood Industrial Park, Southampton – A 170-acre estate on which a gas fired power station and large energy from waste plant were consented and constructed plus a planning consent for 1,000,000 sq ft of B1, B2 and B8 accommodation.

Langley Park, Chippenham – A 48-acre business park on which we secured a mixed use planning consent for employment, residential, leisure and retail, in addition to increasing occupancy levels.

 Glenfinnan also has extensive experience in infrastructure related projects in connection with the automotive logistics sector which involved the consenting and construction of rail terminals and car storage prior to distribution, across the UK including Oxford, Liverpool and Castle Bromwich.

 Glenfinnan identifies sites that are considered suitable for energy development and has been involved in a number of energy projects across the UK including gas-fired power stations, Energy from Waste, anaerobic digestion for both food and farm waste and solar power projects.

First searchable PES database launched – no more guessing

As part of our continuing improving service we have added the UK’s first / only fully searchable PES area database.

All you need is your postcode, and our search tool with query the entire PES area database and tell you exactly which area you are in and who you need to contact about power cuts, new supplies and much more.


New Electricity and Gas Price Graph

In addition to the existing graphs of wholesale power ( and wholesale gas ( we have now launched a price comparison graph, showing both electricity and gas prices in pence per kWh (units), as they appear on domestic and commercial energy bills.  This can be found at


Brexit and Energy Prices

It is hard to quantify exactly the importance of this week on Equities, Currencies and Commodities markets; after months of uneasiness, speculation, argument and counter argument we have reached the week where the UK decides if it wants to remain within the European Union, or become the first ever Nation to leave the group. Another thing that is hard to quantify is just to what extent this vote will have on the UK economy, the Continental Economy or in fact the Global Economy as a whole. Currently opinion polls are pointing to an extremely close run race with the ‘Don’t Know’ category holding the key to the race. Throughout the early part of last week, we saw a shift towards the ‘Leave’ campaign after ‘The Sun’ newspaper declared it’s preference in the vote, resulting in the British Pound taking a battering against the Euro. However, tragic events on Thursday Afternoon saw a definite shift towards the ‘Remain’ camp, with the British Pound rebounding sharply.

This fed into markets overnight on Thursday and throughout Friday, where Oil Prices recovered by nearly $2 /Bl pushing offers close to the $50 /Bl threshold. However, there were mixed messages on the Oil front on Friday, the latest US rig count conducted by Baker Hughes showed that the US added nine rigs putting its total to 337, so it seems that despite low Oil prices there is potential for growth in non OPEC countries, maybe Saudi Arabia’s strategy is not working after all?

Oil Prices have been a strong aid to Gas and Power offers over the last two weeks, where in early June oil prices spiked to $52.51 /bl (its highest level since October 2015) since that point prices fell dramatically towards $47.19 /bl last week, limiting the gains that both Gas and Power could provide after intense volatility in the British Pound. However, it will now be interesting to see how Gas and Power markets react if Oil Prices continue to rise and campaigning resumes on the ‘Brexit’ vote, which may result in British Pound fluctuations.

What we do know is, that both Gas and Power have been increasing over the last week, and prices are now trading at early January offers. As the below graphs can testify:


I expect significant volatility throughout the week as markets try to predict the outcome of the ‘Brexit’ vote, what has become clear is that if the ‘Leave’ vote come out ahead there will be a substantial market reaction (all things being equal) which could lead to a sharp and painful rise in Gas and Power prices by the time we write next week. A ‘Remain’ vote is likely (again, all things being equal) to see far less of a dramatic effect on markets as consequences for losses far more unlikely. Then again, there is no telling what will happen next, 30 minutes tends to feel like days when it comes to the markets at the moment.

Line Loss Factor Class (LLFC) major update

There are industry changes being made to Line Loss Factor Class (LLFC) Identifier codes which we want to make you aware of. This change will take place from 30th June 2016.
What is a Line Loss Factor Class (LLFC) Identifier code?

A LLFC is a three digit numeric code which is used by Distribution System Operators to categorise customer types and voltage levels. This is then used to allocate Distribution Use of System (DUoS) charges according to these categories.

The DUoS charge covers the cost of receiving electricity from the national transmission system and feeding it directly into homes and businesses through the regional distribution networks.

The below diagram shows where your LLFC appears in relation to your MPAN.


What is the change?

The Line Loss Factor Class Identifier code will change from a three-digit numeric value to a three-digit alphanumeric value (consisting of the digits 0-9 as before, and now the capital letters A-Z excluding I and O).

What does this mean to you?

We want to make this change as easy as possible for you, so we are updating our systems to ensure we can process the new alphanumeric form of the LLFC. However, it is important that you bear this change in mind for any systems you or a third party of yours may use, for example for bill validation purposes.

Why is this changing?

There is currently a limited number of LLFCs available to each Distribution System Operator. By making the LLFC alphanumeric, this limitation issue is resolved. This change will increase the number of LLFCs allowing Distribution System Operators to tailor their DUoS charges more specifically at a site level.