Switching house power to generator

Submitted: Friday, May 14, 2010 at 15:49
ThreadID: 78471 Views:7117 Replies:7 FollowUps:16
This Thread has been Archived
Hi all,
I would like to fit a switch into my power box so that when the mains power fails I can set up my generator to keep the fridge and freezer running. Is there such a device? I know that my generator will not run the house as such, it is a EU2.0, but it could keep things cold. We lost power this week for 8 hours straight - a sign of thing to come in Qld?
Back Expand Un-Read 0 Moderator

Reply By: Member - Troll 81 (QLD) - Friday, May 14, 2010 at 15:58

Friday, May 14, 2010 at 15:58
It's pretty expensive to do from what I have heard. I just run a lead from the gennie into the house....
AnswerID: 416673

Reply By: kev.h - Friday, May 14, 2010 at 16:25

Friday, May 14, 2010 at 16:25
Run a lead from the genny -cheapest- otherwise you will need a changeover switch fitted to your meter box which isolates the mains when the genny is plugged in and vise-versa so they cant be both connected at once the genny would have to be earthed as well - expensive
The better option is to run another circuit with separate power points for the genny circuit and fit a caravan inlet somewhere outside and plug the genny into that (that way you don't have issues with the existing power supply) you just swap the fridge over to the other power point then swap back when power is back on. you can get different coloured power points and fit it next to your existing ones as long as they are clearly marked no problems that's the way I did my place
I fitted circuit breakers and earth leakage as well for safety
kev
AnswerID: 416680

Follow Up By: ChipPunk - Saturday, May 15, 2010 at 19:01

Saturday, May 15, 2010 at 19:01
Technically, AFAIK, the genny does not have to be earthed.... unless they have made made appropriate additions to AS3000 (in the past decade or so?), but AS3000 caters for mains connected loads - it didn't cater for power sources.

However, I'd probably inject the power through an RCD (earth leak switch or safety switch (sics) and then earthing does not matter from a safety POV - it is merely used to clear faults (blow fuses) and limit EMI.
0
FollowupID: 686903

Reply By: Member - KC (TAS) - Friday, May 14, 2010 at 16:30

Friday, May 14, 2010 at 16:30
Hi Mikee5, according to a sparkie,who fitted a heat pump for us, I asked the same question, and he said just turn off all your switches, and or pull the fuses. To make sure you don't electrocute some one later.

If you have an outside power outlet, just plug your genny into that.

Good luck with it...
AnswerID: 416681

Follow Up By: Member - Patrick (QLD) - Friday, May 14, 2010 at 16:35

Friday, May 14, 2010 at 16:35
Quote "If you have an outside power outlet, just plug your genny into that"

Pardon my ignorance but what do you mean by that. What is your definition of an outside power outlet?

Cheers

Patrick

0
FollowupID: 686804

Follow Up By: Member - Shane L - QLD - Friday, May 14, 2010 at 16:58

Friday, May 14, 2010 at 16:58
KC you can't be serious can you??? that would mean having a lead with 2 male plugs on it, highly dangerous and illegal. If in fact it was a sparkie who suggested it to you I would have any other work done by him checked by a registered competant sparkie not the hack that told you to do something as dangerous as that.

I install them on a regular basis where I live & work and I only charge $250.00 for a standard install in a meter box that has spare din-rail to mount circuit breaker and change over switch.

Shane

PS what ever you do don't follow this absurd advice
0
FollowupID: 686806

Follow Up By: Allan B, Sunshine Coast, - Friday, May 14, 2010 at 17:07

Friday, May 14, 2010 at 17:07
"Turn off your switches and plug the genny into an outside power point" !!!!!!!!!!!

It honestly amazes me that there are not more people electrocuted !!!!!!!!!!!

Cheers
Allan

Member
My Profile  My Blog  My Position  Send Message

0
FollowupID: 686807

Follow Up By: Member - Roachie (SA) - Friday, May 14, 2010 at 20:46

Friday, May 14, 2010 at 20:46
I know it's WRONG x 1,000,000.....but that is exactly what we used to do when I worked in PNG many years ago. We had HEAPS of power outages and it was common practice to drag out the extension cord with 2 male plugs and hook the gennie up to a power point with the mains turned off (so we weren't trying to power-up the whole bloody town).

As I said, it was wrong by all means; but it kept us "happy".

I do not condone nor recommend this in any way.

I worked in PNG in the days before bicycle helmets, seat belts, twopenny bungers were freely sold to any kid who could afford them etc etc.... people weren't quite so "precious" about safety in those days and (dare i say), they were endowed with a bit more common sense than people of today.

It's a bit like the arguement about germs (in my opinion)..... if you molly-coddle a kid to stop them getting nasty germs on their precious little pinkies, chances are they will not build up an immunity to germs. Likewise, you over-govern what people can and can't do in their own lives and pretty soon they have no level of common sense as to what they can "get away with".

hahahahaha....I love the good ol' days.
0
FollowupID: 686833

Follow Up By: Member - david m2 (SA) - Friday, May 14, 2010 at 21:49

Friday, May 14, 2010 at 21:49
well said roachie
0
FollowupID: 686836

Follow Up By: ChipPunk - Saturday, May 15, 2010 at 19:09

Saturday, May 15, 2010 at 19:09
Definitely not recommended for the unknowledgeable and unqualified... but "we" used to do similar in a foreign country that used 2 round pins (same as out old kettles) - but we didn't have to manufacture any illegal male-male extension - we merely stuck 2 nails in the female end of a legal extension cord. (LOL)

But being in the country, we had 3-phase power and it was not uncommon to lose a phase, so it was used to power the dead phase from the working phases.
And it was VERY IMPORTANT to pull the dead-phases supply fuses - inter-phase shorts are worse than single-phase shorts! (And were very likely to take out BOTH phases when power returned.)

As I just wrote above, I'd also recommend using and RCD between the generator and the load (house etc). (RCD aka Safety Switch etc.)
0
FollowupID: 686907

Reply By: Mikee5 (Logan QLD) - Friday, May 14, 2010 at 17:27

Friday, May 14, 2010 at 17:27
Ok, thanks for the replies.Looks like a change-over switch for around $250. I wouldn't use a power cord with 2 male ends sounds lethal. I have run an extension and powerboard, just thought something more permanent might be the go.
AnswerID: 416688

Follow Up By: Member - Barnray (NSW) - Friday, May 14, 2010 at 20:24

Friday, May 14, 2010 at 20:24
Camec have external input connectors that mount on an outside wall to allow the connection of a 240v supply plug. Barnray
0
FollowupID: 686830

Reply By: Motherhen - Friday, May 14, 2010 at 18:08

Friday, May 14, 2010 at 18:08
Hi Mike

Even if you do have it legally and safely set up, someone is sure to put on too many appliances and trip the genny. Much more practical to run a lead into the house. We do this regularly during power failures that have lasted up to three days. I just rotate the fridges and freezer for one hour each, together with a couple of small appliances such as aquarium pump, reading light, or two way radio if during a bushfire emergency. It will not run things like the water pump and using the electric kettle may be stretching it, so far better to have control and cheaply and safely run an extension cord or two (the Honda has two outlets).

Motherhen
Motherhen

Red desert dreaming

Lifetime Member
My Profile  My Blog  Send Message

AnswerID: 416689

Reply By: Member - barry F (NSW) - Friday, May 14, 2010 at 18:14

Friday, May 14, 2010 at 18:14
We have had the same thing happen now & then but it is not all that often. Sounds like a lot of expense for something that might happen, so if it were me & if I had genny I reckon I would just use an extension lead as already suggested to run the essential things. It's called the KIS Principle,
K eep
I t
S imple & you will have no problems. Cheers
AnswerID: 416691

Reply By: Members Paul and Melissa (VIC) - Friday, May 14, 2010 at 22:04

Friday, May 14, 2010 at 22:04
as a qualified sparkie i dont condone the bone head actions of a double male lead. we have several usually long power outs as we live in the hills and all i use is a lead and power board with a plug in RCD and all is good. i swap the fridge and a few other things around to keep everything ticking over, the fridge/freezer if not opened too often will be OK for hours. if you like i can pot some gory photos of people doing stupid things with and around electricity. like i tell most people, you can see or smell gas and water but you cant with electricity.
AnswerID: 416720

Follow Up By: old patrol - Friday, May 14, 2010 at 22:25

Friday, May 14, 2010 at 22:25
Hi, I just wanted to add a note of caution on the use of RCDs and portable generators - please dont assume that they are functional - portable generators and RCDs are a whole science in themselves.
0
FollowupID: 686839

Follow Up By: Members Paul and Melissa (VIC) - Saturday, May 15, 2010 at 08:35

Saturday, May 15, 2010 at 08:35
yeah true, they can have a mind of their own,dont use those crappy little plug in ones use the larger orange standalone units(portable) as made by clipsal or similar.
0
FollowupID: 686852

Follow Up By: Member - Patrick (QLD) - Saturday, May 15, 2010 at 08:53

Saturday, May 15, 2010 at 08:53
"use the larger orange standalone units(portable) as made by clipsal or similar"

Just what are these units called? I have had a look at the Clipsal site using 'external input connectors' without success.

Patrick

0
FollowupID: 686854

Follow Up By: Member - Patrick (QLD) - Saturday, May 15, 2010 at 09:01

Saturday, May 15, 2010 at 09:01
Ooooops....rereading the post it looks like they are called RCD. You can tell that I am not electrically minded.

Patrick

0
FollowupID: 686855

Follow Up By: Members Paul and Melissa (VIC) - Saturday, May 15, 2010 at 09:42

Saturday, May 15, 2010 at 09:42
also most quality generators have an earthing point,you can buy or make an electrode to put in the ground and "earth" the genset but i have found this can go either way, it can improve the sensitivity and operation of the RCD or make it trip on anything plugged in to it. Go Figure??
0
FollowupID: 686861

Follow Up By: Member - Shane L - QLD - Saturday, May 15, 2010 at 10:16

Saturday, May 15, 2010 at 10:16
As in my earlier post I install the change over switches and input sockets on a regular basis living just north of Gympie as we get frequent outages. Having an earth on the generator is of no real importance as the house earth is used and the RCD/s (safety switch/es) operate as they should. The only time there are problems is when the generator has an RCD fitted, this will trip when the genie is connected to the input socket because of the MEN (multiple earthed neutral) at the house switch board. The first time I had this problem was when a customers genie died and they hired one that was fitted out for construction sites with an RCD, This client had a very small solar system and needed the genie to charge his batteries.
There are a lot of houses around where I live that are on pure solar (batteries & Inverters) that are "under panelled" and rely on a generator to top up batteries during the day, some systems I have seen are only 750watt inverters with very small amphour reserve of batteries, I have done the 240v side of a few "proper" installs (5-7 Kw) that still have the input socket to top the batteries when required, same change over switch and input socket I install for those on mains.
As for overloading genie - I advise customers to NOT try and use high load devices such as laser printers, Hot water services, airconditioners cookers etc as most only use a 2.0 kva genie, I have got the input socket where I am renting and have worked out what I can and can't run off the genie and turn off those things when I put the genie on, we rely on tank water where I live (whole area) and to even go to the toot requires power for the water pump, thus they really are a necessary part to life up here.

Shane
I hope this has provided a bit more clarity for some of you
0
FollowupID: 686862

Follow Up By: ChipPunk - Saturday, May 15, 2010 at 19:23

Saturday, May 15, 2010 at 19:23
Interesting that Paul and Melissa (FU5 above) reckon RCDs are more sensitive with earth (stakes).
RCD operation should not require earth - they operate if there is an imbalance between its two "lines" (aka active & neutral).

Inverter installations had this issue - leave it as a floating system whereby you could touch EITHER AC line and not be electrocuted (but touch both and you would be!), or "create a hazard" by tying one side to earth (the M.E.N. system) thereby touching Neutral was non-hazardous, but Active was.
However RCDs solved that issue. (Why people wanted to earth them for safety before that was beyond my comprehension; post-RCD it's a no-brainer situation.)

An inverter is no different to a generator.
0
FollowupID: 686916

Follow Up By: ChipPunk - Sunday, May 16, 2010 at 10:19

Sunday, May 16, 2010 at 10:19
I forgot the reliability issue....

RCDs have been around for ages but it wasn't until the 1990s that they became stable enough for domestic use.
They would often trip due to surges, electrical noise (eg PC power supplies) etc.
But they overcame most of those problems.

That's not to say they will not falsely trip on generators. As mentioned above - there are many factors - frequency variations and transient responses that are not present in mains supplies.

But I suggest using an RCD and if it does falsely trip, get a better RCD. Or omit it.
When RCDs were first legislated, lighting and refridgerator/freezer circuits were exempt in acknowledgment of false tripping potential. (I think ovens & stoves are still exempt?)

Ha - and you thought I was gonna talk about why SAA did not want them called "Safety Switches".
0
FollowupID: 686964

Sponsored Links

Popular Products (14)