Generator Questions

13 July 2023

Diesel Generators are the unsung heroes of the machinery world, they  continue to provide life, electricity and support around the world day in day out. Reliable robust machines that see us through disasters, emergencies and every day life. That being said most people don’t  know what a generator is even though I can guarantee that one has been used to provide you power at some point in your life even without you knowing. However even if you do know what a generator is and does they come with a whole host a technical terms and parts that perhaps you are not sure about. Let us help.

Over in our Knowledge Centre we have a wide selection of useful information that will help you from manuals, to Jargon Busters.

Here below are a few explanations of generator jargon to help.

• What is kVA? –  . A term used for rating of an electrical circuit, which is the product of the circuit maximum current and voltage rating. Also known as apparent power. i.e – Volts x Amps.

• What is kWe? – Kilo Watt Electrical. In 3 phase generators it is the kVA x 0.8.

• What is 3 Phase? –  3 Phase consists of 5 cables: 3 live ( L1, L2 & L3), a neutral and an earth. Typical voltages are 400-415 Volts between the live cables ( eg. L1-L2) and 200 -240 Volts between the live and neutral. hence a three phase system is often given the voltage as 415/240V.

• What is single phase? – A single phase supply consists of 3 cables: Live, neutral and earth. Typically the voltage is 220-240 Volts. Domestic houses have single phase supplies. Current will flow through only the live wire and there will be one return path (neutral) to complete the circuit.

• What is frequency? – The rate at which the current changes direction per second. All UK frequency is 50 Hz i.e 50 cycles per second. UK generators are rated at 50 Hz plus or minus a tolerance.

• What is a Load Bank? – Load banks provide load for generating set(s) for test purposes. Most are resistive load banks which you can imagine as a very large heater that pulls load from the generator during testing.

• What is a Governor? – A device for controlling fuel to the engine to maintain speed under varying load conditions.

• What is an AC generator? – An electrical generator that produces Alternating Current.

• What does Autostart mean? – The ability of the generator to start automatically after a mains failure by receiving a signal usually from an automatic transfer switch.

• What does Automatic Mains Failure (AMF ) mean? – The ability of the generator to monitor  the mains supply and start automatically upon its failure.

• What is an Automatic Transfer Switch (ATS)? –  A device that safely transfers load from the mains to the generator upon mains failure and back again upon mains restoration.

• What is a Base load? – The portion of load of a generator or building which is constant. Alternatively referring to a constant generator output when in parallel with the grid.

• What is Synchronising? – When multiple generators or generators and the grid work together. Synchronising refers to the voltage, frequency, power factor all being the same i.e in sync with one another.

• What is a UPS? – A device, usually consisting of a controller and multiple batteries that provides uninterruptible power to a building upon mains failure until more sustainable forms of power become available. e.g diesel generator.

• What does Dump Line mean? – Refers to the safeguarding method of using a pipe work system to ‘dump’ fuel away from a day tank when there is a potential fire risk.

• What are Fuel Lines? – Pipelines from an engine to a fuel tank or from one fuel tank to another fuel tank.

• What is a Bulk Tank?  – A large storage tank from which the generating set may take its immediate supply of fuel. The bulk tank generally is the receiving tank for fresh fuel supply. The bulk tank may be used to provide a supply to a day tank, then to the generating set.

• What is Bunding? – Bunding, also called a bund wall, is a constructed retaining wall or bank around storage. Generally seen around large fuel tanks, but can be used around smaller tanks. Smaller tanks can have integral bunds, often called twin skin or twin wall tanks or “self bunded tanks”. Containerised generating sets are often bunded by sealing of the container floor.

• What is a Current Transformer (CT)? – A current transformer (CT) will produce a current, in its isolated secondary circuit proportional to the current in the main circuit being measured. Standard currents in the secondary are 1 A and 5 A at the rated primary current. CT’s are used to display the Amps on the control panel.

• What is Duty Assist? – An arrangement where two (or more) generating sets are configured to provide mutual support in case of one piece failing to operate or needing assistance to achieve a required target: If one generating set fails to operate or cannot achieve a required target, the second (and subsequent) generating set will operate.

We understand that generators and power generation can be a lot to get your head around, that is why we are here to help. If you have any questions at all please call our friendly support team who will help you – 01270 821 419 or send us an email  support@fwpower.co.uk.