Discuss How would you know that you have had a power cut and electricity is coming through a generator instead of mains? in the Electrical Forum area at ElectriciansForums.net

Welcome to ElectriciansForums.net - The American Electrical Advice Forum
Head straight to the main forums to chat by click here:   American Electrical Advice Forum

tasj96

DIY
Reaction score
0
Hi
sorry for the vague question. I'm looking more of a starting point.

What do you have in place to know whether you are running on mains power, UPS, or a backup generator?
If the mains should fail how would you know, how can you monitor it, and when it comes back active how would you know?
Thanks for any help.
 
Most generators make enough noise that you know they are running! Many systems will allow you to connect remote indicator lights from the changeover panel to somewhere convenient inside the property so you can see what is currently supplying power.
A crude version is shown below:
How would you know that you have had a power cut and electricity is coming through a generator instead of mains? 1611684457505 - EletriciansForums.net
 
Most generators make enough noise that you know they are running! Many systems will allow you to connect remote indicator lights from the changeover panel to somewhere convenient inside the property so you can see what is currently supplying power.
A crude version is shown below:
View attachment 64078
More advance systems can send text messages to report power loss etc.
 
As above, if you are on-site you probably know already.

However, for remote support you have to have some system in place to monitor what is providing the power. Otherwise mains fails, generator kicks in, everything on UPS works flawlessly and then 10 hours or so later it all falls over as the generator ran out of fuel...

Also if it is industrial/data centre make sure the A/C is on the generator and all adequately rated, otherwise you don't get to out-of-fuel as 15 minutes or so in to the outage things overheat and fail.
 
You could buy and fit a current clamp around the grid incomer line, another for the generator and one for the ups. The current clamps I have in mind have an integral switch which closes when the current exceeds a preset level. You could use these outputs to provide signals indicating current flow. I will find an example and post details.
 
Well for most people, they'll know if they're running off a genny as they'll have had to go and change over the supply and start the genny. A UPS will generally start beeping, and stuff that isn't on the UPS will all go off when the mains fails.
So to answer the question, you really need to narrow down the question a bit. Is this for a small installation with manual changeover and a portable genny ? Or a massive industrial site with massive UPS systems and automatic failover to generator ? Something else ?
Some generator installs can be paralleled with the mains rather it being an either/or situation. Many businesses use this to make money from providing STOR capacity to the grid, as well as allowing them to fully load the genny for testing and turn over their fuel. STOR = Short Term Operating Reserve, stuff that can be called up in double quick time to deal with (e.g.) loss of a large power station, but only for a short time while something bigger is fired up.

So, what is the scenario in question ?
 

Reply to How would you know that you have had a power cut and electricity is coming through a generator instead of mains? in the Electrical Forum area at ElectriciansForums.net

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Electrical Goods - Electrical Tools - Brand Names Pushfit Wire Connectors Electric Underfloor Heating Electrician Courses
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc

Electrical Forum

Welcome to the Electrical Forum at ElectriciansForums.net. The friendliest electrical forum online. General electrical questions and answers can be found in the electrical forum.
This website was designed, optimised and is hosted by Untold Media. Operating under the name Untold Media since 2001.
Back
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock