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  Reply # 2015103 13-May-2018 13:10
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My APC UPS has refused to use either of my small inverter generators or a car 12v powered inverter as in input. Just sat there on battery despite there being power going into it and other things on the same source running fine. Would run off another UPS tho which is weird.

 

When I finally gave up and got the big 33000w ozito generator, then it was happy enough to be on passthru power most of the time. It would click to battery everytime something else powered on briefly, and putting 2 UPSs on it made them basicaly ping pong around which was powered and which was on battery. They were both running tiny loads - one the router, adsl modem, small switch and a couple of NVRs in one rack, the other running the big POE switch and a baby NAS in another rack.

 

The 3300 is also able to run the fridge, which the small 700 and 1100 watt ones could not.

 

Its just noisy. really noisy. Like cant run it at night noisy.

 

Guess when all the long outages happen. Factor noise into your decision process. They spec it at 67dBA at 7 meters. That is insanely loud when put outside away from the house, and will really annoy those around you who are sitting in the dark and quietness of no power reading facebook on their phone screens.





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  Reply # 2015115 13-May-2018 13:56
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richms:

My APC UPS has refused to use either of my small inverter generators or a car 12v powered inverter as in input. Just sat there on battery despite there being power going into it and other things on the same source running fine. Would run off another UPS tho which is weird.

 

 

That sounds like the issue I mentioned earlier where the UPS detects that the input doesn't look close enough to a good mains source and switches to battery to protect the equipment behind it. Are the inverters simulated sinewave (i.e. stepped square wave) or something similar, or do they have problems holding frequency or voltage? And I'm guessing the other UPS is a pure-sinewave one.

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  Reply # 2015164 13-May-2018 15:02
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I remember reading an article about black market products during the Sarajevo war/seige.

 

Top of the list was electric generators along with comment that you had to (armed) guard them because people would steal them and the noise they made meant they were very difficult to hide from potential armed robbers !!


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  Reply # 2015247 13-May-2018 17:16
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As I said, I make sure mains power is totally switch off before I start, at main switch board and the main power board at the meter box.
There is absolute no room for mistakes.
As I said, it is a suicide plug and use at your own perils.

But the point is that a emergency generator/inverter is just that.
It is absolute no point to get something that has the power to run everything.
And you need to price your equipment to suit.

I only need to keep my water pump, and my freezers running in a EXTENDED power cut.
The fact that it can run my pc without damage is a bonus but not necessary.
Since the Big Power Cut, my Honda is left as is, and will probably be gathering dust.


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  Reply # 2015660 14-May-2018 12:09
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Please, Nobody else build a "Suicide cord" (male to male power lead). The name makes it pretty clear, but for clarity, these are both dangerous and illegal.

If you want to liven your whole (or a portion) or your homes wiring, the only legal way to do it is to call a sparky, and have them install a generator inlet port (plug/socket?), and a transfer switch. Shouldn't cost more than a few hundred dollars.

Otherwise, leave the house wiring dead, and throw an extension cord through the window, and use a power board to power critical appliances. (salvage some desk lamps for lighting).



Hunter: As I said, I make sure mains power is totally switch off before I start, at main switch board and the main power board at the meter box.
There is absolute no room for mistakes.
As I said, it is a suicide plug and use at your own perils.

 


The general approach for electrical safety in NZ is that everything needs to be pretty much idiot proof. With the suicide cord, an emergency services worker (police / ambulance) who is called to your house, may decide the cord is in the way and unplug it, exposing the live contacts. There is a risk that the grid isolation stuff is done wrong, and that you liven the whole street.

also consider that while extremely unlikely for 2x switches, it is possible for switches to fail on (welded closed), in this case, you would have no way of knowing that your house is not isolated from the street.


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  Reply # 2015713 14-May-2018 13:23
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Scott3:

 

The general approach for electrical safety in NZ is that everything needs to be pretty much idiot proof. With the suicide cord, an emergency services worker (police / ambulance) who is called to your house, may decide the cord is in the way and unplug it, exposing the live contacts. There is a risk that the grid isolation stuff is done wrong, and that you liven the whole street.

also consider that while extremely unlikely for 2x switches, it is possible for switches to fail on (welded closed), in this case, you would have no way of knowing that your house is not isolated from the street.

 

 

I thought the whole purpose of isolators as opposed to switches was that they would refuse to move to the off position if the contacts didnt actually open?

 

Anyway, yeah dumb idea and dont do it. But the few hundred for a change over switch is a little optimistic for most installations I would think.





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  Reply # 2015723 14-May-2018 13:34
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richms:

 

Scott3:

 

The general approach for electrical safety in NZ is that everything needs to be pretty much idiot proof. With the suicide cord, an emergency services worker (police / ambulance) who is called to your house, may decide the cord is in the way and unplug it, exposing the live contacts. There is a risk that the grid isolation stuff is done wrong, and that you liven the whole street.

also consider that while extremely unlikely for 2x switches, it is possible for switches to fail on (welded closed), in this case, you would have no way of knowing that your house is not isolated from the street.

 

 

I thought the whole purpose of isolators as opposed to switches was that they would refuse to move to the off position if the contacts didnt actually open?

 

Anyway, yeah dumb idea and dont do it. But the few hundred for a change over switch is a little optimistic for most installations I would think.

 

 

 

 

Given you need a mains voltage diode that will stop mains from back feeding into your generator and creating a bomb when its plugged into your home.






 


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  Reply # 2015738 14-May-2018 13:54
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If using a diode, what happens when your generator's zero crossing point is aligned with the network's  peak voltage ?

 

Bang ! is what happens.

 

A double throw changeover switch sounds like a better idea.


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  Reply # 2015740 14-May-2018 13:55
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Scott3:

Please, Nobody else build a "Suicide cord" (male to male power lead). The name makes it pretty clear, but for clarity, these are both dangerous and illegal.

 

 

So you mean this cable for my powered hub is illegal?

 

 

 

 

I never would have known...

 


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  Reply # 2015745 14-May-2018 13:58
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Coil:

Given you need a mains voltage diode that will stop mains from back feeding into your generator and creating a bomb when its plugged into your home.


 

 

That would be one of those AC diodes? I've seen them in the US, they're implemented using magnetic monopoles bolted to a frictionless surface and rely on quantum migration of solitons for effect. Quite clever when you think about it.

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  Reply # 2015747 14-May-2018 13:59
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neb:
Scott3:

Please, Nobody else build a "Suicide cord" (male to male power lead). The name makes it pretty clear, but for clarity, these are both dangerous and illegal.

 

 

So you mean this cable for my powered hub is illegal?

 

 

 

Answering my own question with a head-slap, of course it's illegal in NZ, it has a European power plug on it.

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  Reply # 2015754 14-May-2018 14:05
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neb: So you mean this cable for my powered hub is illegal?

 

This is not an approved PoE injector  :)

 

 

 

 


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  Reply # 2015759 14-May-2018 14:15
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elpenguino:

 

If using a diode, what happens when your generator's zero crossing point is aligned with the network's  peak voltage ?

 

Bang ! is what happens.

 

A double throw changeover switch sounds like a better idea.

 

 

 

 

Ya got the jist, Couldn't recall exactly what was needed but knew a Diode prevented power from going backwards.
Pretty much an isolator that means only House-Generator/House-Mains can be active at one time. What about residual current in the house when you switch from mains to generator power in the case the power was not cut?





 


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  Reply # 2015760 14-May-2018 14:16
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neb:
Coil:

 

Given you need a mains voltage diode that will stop mains from back feeding into your generator and creating a bomb when its plugged into your home.


 

That would be one of those AC diodes? I've seen them in the US, they're implemented using magnetic monopoles bolted to a frictionless surface and rely on quantum migration of solitons for effect. Quite clever when you think about it.

 

 

 

 

 

Those are the things that make the UPS work and go DONK when it loses power??





 


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  Reply # 2015778 14-May-2018 14:36
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Item:

 

With the threat of a more tropical climate becoming the norm and the increased likelihood of more frequent or severe power outages or "emergency conditions" I really need to get my butt in gear and build a proper, robust emergency kit.

 

One of the things I was considering was a small diesel generator/inverter - enough to run a few household essentials and charge devices etc.

 

     

  1. Are these worth having?
  2. What brands and specs/features should I look for?
  3. Can you get a decent "buy it for life" unit for under $1000?

 



1.

 

As a general rule no. Most urban New Zealand houses do not have backup generators (OP lives in West Auckland). The NZ power network is pritty stable, we don't have seasonal extreme weather events (such as tornadoes, typhoons etc.). Resolution times for power outages in nz urban areas are generally fairly fast. Also, power cuts (with an obvious exception to two) are rarely citywide, so many people can charge their phones etc at work, or at a friends (or families) place. Many people have a BBQ that they can cook on in a power cut, and Auckland climate is mild enough that people can rug up and survive without heating for a few days.

Backup generators are fairly expensive, require regular running (maintenance running), and servicing. They are noisy to run, and are fairly bulky to store. Also to be of any use, you need to have a stockpile of fuel (which is both bulky and hazardous to store). Note that you require special certificates to legally store more than 50L of petrol at home (excluding any petrol in vehicle tanks). Smaller, cheaper generators also generally require fueling every few hours.

If you have a car, and somwhere you are happy to leave it running, perhaps consider buying a nice inverter, and using that to keep your freezer cold (couple of hours a day should be enough if you don't open it), and your devices charged.

That said, I think one would be well worth having in the following circumstances:

 

  • You want one to operate powered equipment away from the house (such as table / drop saws, heat guns etc).
  • You have an un-usually high value of frozen goods, that could be damaged in a power cut.
  • You require power at home to make a living, such as somebody who has a home based business, or works from home (and cannot commute if there is a power cut).
  • You require power for your water or sewage systems to work.
  • You require power for medical equipment. (or other medical reason, such as poor health requiring a warm house)
  • You have an elevator (Requires automatic start & fallover, so you don't get stuck).
  • You have the money, and are willing to pay for the luxury avoiding power failures.

 

 

2.

Biggest thing you will want to look for is low noise. Open frame 3000RPM generators are super noisey, and will annoy yourself and your neighbors. Most generators have a noise rating. Also check the weight, if you want to be able to lift it (many come on wheels, so you man not need to lift it if you have space to store on the floor). Check the run time on a tank of fuel. Bigger 1500RPM diesel generators often come with an outdoor acoustic enclosure, so no need to store it inside.

Other thing to decide is weather you are happy to throw an extension cord in through a window, of if you want to have a generator connection plug, and transfer switch installed in your house, so you can safely run the generator through the house wiring (you would want at least a 4000W generator to do this.)

Next question is fuel.

 

  • Petrol generators are cheaper, and lighter than diesel, but the fuel goes stale, so you will need to turn it over every 6 months (easy if you have a petrol car) generally these run at 3000RPM (or variable RPM). If you want to be able to lift your generator, get petrol.
  • Diesel generators are much cheaper to run. Basically all the good diesel generators run at 1500RPM, and will set you back $10k, and will need lifted into place with a hoist of some sort. These 1500RPM diesel generators are capable of running "duty" as well as "standby", and will give many thousands of hours of service. Quiet models are available.
  • Natural gas generators are fairly rare in NZ, but if your main concern is storms, these are a great option, and very popular in places like Florida. In short, natural gas pipes are underground so typically unaffected by storms. Running off piped natural gas gives you infinite run time, and removes issues with fuel storage, and refueling that go with liquid fueled generators.


3.

$1k, will buy you a used branded (Not honda, but there are a few nice Yamaha generators on trademe at the moment), or a new no name portable petrol generator. I would expect these to last under a decade. 

 

I don't think any generator would be a buy for life item, they have moving parts, and are prone to corrosion etc. That said, a brand name 1500RPM diesel generator which is well maintained (including "loaded" scheduled maintenance runs, and has a heater to prevent condensation on the electric machine component) should last well upward of a decade. 


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