Blog posts of '2022' 'February'

Why An Automatic Transfer Switch Is Preferable To Manual

If you have a standby generator for your home or business, then you are one step ahead of many of the population. There is an increased risk of power outages due to climate change and the rise in global power usage, so having a generator that can jump in and continue to provide the power that you need makes a lot of sense.

You won’t have to worry about not being able to use the TV, the water going cold, and all the food in the freezer defrosting. If the power goes down, as long as you have the right sort of generator, you can last for days. It is like having an insurance policy. If you are going to buy a generator, it is important to get one that is the right size for your needs, and for this you need to calculate the wattage required or get an electrician to do it for you.

Whatever type and size of generator you buy, it is a legal requirement that you have a transfer switch. This can be either a manual transfer switch or an automatic transfer switch. A manual transfer switch is less expensive but does have disadvantages. As the name suggests, you have to switch over to the generator by hand and then go and start the generator. Not a lot of fun if Storm Fred is blowing a hooley and you’ve got to go outside to do that.

Goodbye To All The Food In The Freezer

Furthermore, if you have things that you need to keep powered and you happen to be away from home for three days, then there is nobody on hand to transfer and start the generator. So, you can say goodbye to all that food in the freezer, and to your tropical fish if you have them. Equally, you have to shut down the generator and switch back to the mains when the power comes back up.

Now, an automatic transfer switch does all this for you. It detects when the mains power goes down, starts the generator, and when that is up and running at full power switches over to the generator. This all happens in a matter of seconds. Equally, when the mains power is restored, the automatic transfer switch will close down the generator and switch back to the mains.

So, it really is a matter of choice, but despite the extra expense, an automatic switch is by far and away the best idea. 

How A Manual Transfer Switch Works

It seems that more people these days are investing in a standby generator in order to provide electricity to the home or business when the mains power goes down. This happened quite a bit recently in Scotland with all the storms that we have been having. There seems to be no doubt that climate change is an issue, and that means that those storms could become more frequent. This writer is old enough to remember the Great Storm of 1987 when our home was without power for 13 days! Fortunately, we had an oil-fired Aga cooker. If we hadn’t, we would have been in serious trouble.

In addition, of course, there is the threat of a lack of gas supply coming from Russia, and this could be used as a weapon by Vladimir Putin.

So, it makes sense to many people to have a standby generator to step in when the mains power fails. But how does the generator work?

Most generators run on diesel, and they can be started either manually or automatically when the power fails. Every generator must have either a manual transfer switch or an automatic transfer switch.

If you have a manual transfer switch you need to manually turn a handle or alternative lever to switch from the mains to the generator and then start the generator by hand as well.

Required By Law

In fact, a transfer switch is required by law in every country when you install a generator at a premises that has a mains supply. This is for two main reasons, one being that it stops the mains power coming into contact with the generator when the power is restored, which would almost certainly burn out the generator.

More importantly, it prevents the generator from back feeding the mains when it has failed which could endanger the lives of the electricity utility workers.

So, you switch from mains to generator manually and then go and start the generator. When the power is restored, you would then switch off the generator and manually switch back to the mains.

While a manual transfer switch is cheaper than an automatic one, the latter does have certain advantages. Apart from anything else, it is much faster, because it automatically starts the generator and then switches to it in seconds. If you are not on the premises when the mains fails and you use a manual switch, then you are without power until somebody returns and switches over.