Frequently Asked Questions

Things To Consider When Choosing A Generator

We understand that choosing a generator can be a difficult and sometimes time consuming process. There are so many generators to choose from, so how do you make up your mind? Well, we’re sure this blog will help. We’re going to outline a few of our frequently asked questions in order to help you gain a better understanding of generators and which of our generators will benefit you the most.

Frequently Asked Questions

What Size Of Generator Do I Require?
All electrical products are equipped with a data plate with information regarding their power usage. For a lot of power tools, their listed wattage is all the power that they require to run. Household items such as freezers, fridges, washing machines and some lawn mowers are different. Whilst they can state a wattage rating, they can require a much greater requirement on startup, and a smaller usage once started. If you’re unsure what the power usage of a product is, you can always get in touch with the manufacturers, tell them the model number and request the start uprunning wattage of your product. Once you have this information, you’ll know which size generator you require.
Can I Use A Personal Power Breaker?
A generator is configured quite differently to the mains supply. The generator has something which is called a floating earth, whilst the mains has an earthed neutral. It is highly recommended to use a personal power breaker from the mains, it is not necessary to use one with a generator. Personal power breakers are specially designed to operate from the mains; if one is used with a generator, it is necessary to modify the generator so that it is configured in exactly the same way as the mains.
How Do I Connect A Generator To My House?
A few precautions must be observed when you are connecting a generator to your house. It is of vital importance that the generator is isolated from the mains supply. This helps to ensure that the generator is not attempting to power up the whole neighbourhood, but also makes sure that it does not electrocute a utility worker trying to restore the mains supply. To properly achieve this, a double-pole, break-before-make changeover switch must be installed by a qualified electrician. This switch must be fitted between the electricity meter and the building consumer unit. The switch connects the building to either the mains supply or to a lead which can be plugged into the generator itself.
Can I Operate Sensitive Equipment From My Generator?
Well, the output from a portable generator is not as stable as the supply from the mains. The speed of the engine which drives the alternator is controlled by a simple yet effective mechanical governor; therefore, the speed drops as the load is increased. The frequency of the output voltage is directly dependent on the engine speed, which means that the frequency of the output varies with load. Additionally, the output voltage will vary with load and with temperature. Most standard generators will have an output voltage of 230v +/- 1-% from no load up to the rated load current quoted on the data plate. We advise that you always ask the equipment supplier whether their equipment is suitable to be operated from a portable generator.
What’s The Difference Between KW and KVA?
The main difference between KW (kilowatt) and KVA (kilovolt-ampere) is the power factor. Unless it is defined and known, the power factor is an approximate value, and the KVA value will always be higher than the value for KW. In relation to commercial and industrial generators, KW is most commonly used when referring to generators in the Unites States, and a couple of other countries that use 60 Hz. The majority of the world use KVA as the primary value when referencing generators. Generators are usually shown with both ratings and to determine both the KW and the KVA ratio, this formula is used: .8 (pf) x 625 (KVA) = 500 KW
What Is A Power Factor?
The power factor is sometimes referred to as ‘pf’, and is typically defined as the ratio between kilowatts (KW) and kilovolt amps (KVA) that is drawn from an electrical load. Power factor is determined by the connected load of the generator; the power factor on the nameplate of a generator relates to the KVA and KW rating (see the above formula). A generator with higher power factors transfer energy to the connected load more efficiently, while generators with a lower power factor are not as efficient and result in increased power costs. The standard power factor for a three phase generator is .8.
Standby, Continuous and Prime Power Ratings: What’s The Difference?
Standby generators are most often used in emergency situations, such as during a power outage. It is ideal for applications that have another continuous, reliable power source such as utility power. It’s recommended usage is most often only for the duration of a power outage and regular maintenance and testing. Prime power ratings can be defined as having an ‘unlimited run time’, or essentially a generator that will be used as a primary power source and not just for standby or backup power. A prime power rated generator can supply power in a situation where there is no utility source, as is often the case in industrial applications like mining or oil and gas operations. Continuous power is similar to prime power but has a base load rating. It can supply power continuously to a constant load, but does not have the ability to handle overload conditions, or work as well with variable loads. The main difference between a prime and continuous rating is that prime power gensets are set to have maximum power available, at a variable load for an unlimited number of hours. They generally include a 10% or so overload capability for short durations.
I’m Interested In A Generator That Is Not The Voltage I Need… Can The Voltage Be Changed?
Well, generators are designed to be either reconnectable or non-reconnectable. If a generator is listed as reconnectable, the voltage can be changed, ergo if the generator is non-reconnectable, it is not changeable. 12-lead reconnectable generator ends can be changed between three and single-phase voltages; however, be sure to keep in mind that a voltage change from three phase to single phase will decrease the power output of the generator.
Can A Generator I’m Looking At Run Parallel With One I Already Own?
Yes, generator sets can be paralleled for either redundancy or capacity requirements. Running generators parallel to each other allows you to join them electrically, to combine their power output. Paralleling identical generators will not be problematic but some comprehensive thought should go into the overall design, based on the primary purpose of your system. Now, if you’re trying to parallel unlike generators, the design and installation can be more complex. It’s important to keep in mind the effects of engine configuration, generator design and regulator design.
Is It Possible To convert A 60 Hz Generator To A 50 Hz Generator?
Generally, most commercial generators can be converted from 60 Hz to 50 Hz. The general rule of thumb is 60 Hz generators run at 1800 Rpm, and 50 Hz generators run at 1500 Rpm. With most generators, changing the frequency will only require turning down the Rpm’s of the engine. In some cases, parts may have to be replaced or further modifications made. Larger machines or machines already set at low Rpm are different and should always be evaluated on a case by case basis. We prefer to have our experienced technicians look at each generator in detail, in order to determine the feasibility and what will be required.
How Do I Know What Size Generator I Require?
Getting a generator that can handle all of your power generation requirements is one of the most important aspects of the purchasing decision. If you’re interested in prime or standby power and your new generator is unable to meet all of your specific requirements, it won’t be doing anyone any good. Determining exactly what size of generator you need is often very difficult and involves a number of different factors and considerations. It’s easiest to make a list of things you’ll need to consider, including: Items that need to be powered by the generator. A note of the starting and running wattages of the items. The total power requirements in KVA and KW.

Why Choose Us?

There are several reasons why you should choose Bellwood Rewinds for generator hire. We have listed a few of these below:


Reliable Generators

All second-hand systems are repaired and serviced before we make them available for hire. All new systems are checked and serviced too, ensuring they are fit for customer use. We are proud of our ultra-reliable generators.


Broad Range

We have a wide range of generators to choose from. We offer advice and guidance to make sure you get your hands on the backup power source you need.


Competitive Prices

Our generators are competitively priced. If you are looking for a cost effective solution for backing up your power, we can find something to suit your requirements.


Expert advice

For those of you that aren’t sure which generator to hire, we can help you. We have years of experience specialising in the sale and rental of generators and will happily talk you through your options.

Contact Us Today

We hope that our answers help you with whatever it is that you need. If not, you can give our team of generator specialists a call on (0)1429 264 097.