Suzuki Generator

[nonthaburial]

I have been offered a SUZUKI SV1000H generator at a very reasonable price. My plan is to wire it into my house for backup use during the very frequent "blackouts" suffered.

I realise that this is not a large generator, but can anyone tell me if this would be big enough to give me a few lights, a few fans, a fridge and a TV. I would also be interested to hear if this model has a safety trip fitted where it shuts itself down if the main power should come back on.

Many thanks

[Tywais]

It looks underrated for the appliances you show. It has a .7 kVA rating. Applying a power factor of, just an example, .85 you will have about 600 Watts of useable power. So the refrig may be an issue depending on if it has a good power factor correction in it.

kVA TO kW kVA * .85 = SAME VALUE EXPRESSED IN kW

where .85 is the power factor and is a variable depending on the appliances.

[Crossy]

Definately a bit small, probably won't run the fridge Telly, a few lights and fan OK.

If you wire it in you need a change-over switch (auto or manual) it is ABSOLUTELY VITAL that the genset and incoming mains are NEVER EVER EVER connected together.

Should this happen and the mains is on, the genset will take a short flight into the hereafter, if the mains is off you will try to power the whole area, not going to happen with such a baby unit(together with the very real danger of killing some poor lineman who thinks the juice is off).

Most people with baby gensets just run a traily lead from the output and plug in the things they want to run.

DO NOT use the Thai method of a lead with a plug on both ends which you insert into one of your outlets, effective but potentially deadly.

[nonthaburial]

Thanks for the replies, as I guessed a baby doing a mans job !! however fridge aside it does appear that this may run a few fans and minimum lighting.

Crossy - I understand your comments on "mains in "and Genset operating at the same time, but surely the safety device would have to be automatic as its would be imossible to manually override when the power came back on. Would this safety device be expensive ?

[Naam]

but surely the safety device would have to be automatic as its would be imossible to manually override when the power came back on. Would this safety device be expensive ?

most probably more expensive than your baby genset. the easiest way is to install a manual changeover switch (somebody mentioned that already). you can wire a light to the mains which will alert you when power is back and you can manually switch from generator to public power supply.

[Crossy]

In it's simplest form the change over is simply a manual switch with 2 inputs and one output.

Input 1 -- mains

Input 2 -- genset

Output -- stuff you want to run.

Switch in position 1, your kit runs from the mains. When the mains fails you start the genset and move to position 2, kit runs off the genset.

When the mains returns move back to position 1 and stop the genset.

The 2 position switch ensures you never connect the two supplies together. Any reasonable electrician should be able to knock one up from standard electrical parts.

Obviously you need a light somewhere to tell you that the mains has returned

Should cost a few 000 baht.

For automatic switching you really want an autostarting genset that senses the load and fires up on its own. Auto switches are more specialist (read expensive).

If you want I can draw up a semi-automatic unit that you can show to your electrician, he may even be able to build it

[Tywais]

For automatic switching you really want an autostarting genset that senses the load and fires up on its own. Auto switches are more specialist (read expensive).

A heavy duty double pole double throw relay will make the switching automatic and probably not too expensive. However it appears the unit is a manual start so still some hands on required so maybe the manual switch (again heavy duty) is the simplest route. The lightbulb across the mains is a good idea.

[Crossy]

A heavy duty double pole double throw relay will make the switching automatic and probably not too expensive. However it appears the unit is a manual start so still some hands on required so maybe the manual switch (again heavy duty) is the simplest route. The lightbulb across the mains is a good idea.

Actually what I was going to suggest as a 'semi-automatic' solution, a small consumer unit box, 3 MCBs (or 2 + a small fuse) and a 2xNO+2xNC 220V contactor (relay).

We're only looking at <5A so a beefy relay would actually do the job just fine, need to find one with a 220v coil though (not so available).

The other advantage of using a contactor is that it will fit directly on the DIN rail in a consumer unit box easy to put together and wire up.

[monty]

I wouldn't run a small genset like that automatically.

You'd still have to pull start it anyway, but if you connect it to the mains by using either a throw over switch or a magnetic contactor you'd be required to go around the house shutting down everything like aircons, pumps, fridges etc before you could start the thing.

Just using an extension lead and plug in what you need would be the easy way!

Otherwise, you'd have to designate a seperate breaker in your breaker box on which just some ceiling fans, the plug of your telly and some lightpoints are connected.

Then you can feed this breaker from either the mains or the genset...

[nonthaburial]

Thanks all, I feel the last para from Monty is looking the more likely, however can anyone tell ,me the power required to run a average size fridge and ceiling fans please

[Tywais]

Thanks all, I feel the last para from Monty is looking the more likely, however can anyone tell ,me the power required to run a average size fridge and ceiling fans please

Take a look here > Power Requirements

and here > Emergency power

[monty]

Your genset is .7kva, which equals roughly to 600 watts as Tywais pointed out earlier.

This means you can load the generator with up to 600 Watts of appliances.

Practically this only works for non inductive (resistive) appliances, such as heating elements, regular lightbulbs etc...

Inductive loads (motors, pretty much anything working on an electro magnetic base) generally need an inrush of electrical current much higher then their normal rating just to get going.

For you fridge for example, this would mean that a 400 watt compressor would need maybe 2000 watt worth of current for maybe half a second to start up. Same for a waterpump, even a television set has a pretty big current peak if you start it up...

I very much doubt that your genset could get the fridge going, when it wants to start, the fridge will draw more amps then the genset can deliver causing the voltage to drop down. The fridges compressor will not be able to overcome the initial resistance to start turning, it'll just hum and if the breaker doesn't pop out it'll get very hot until the thermal safety built in shuts it down...

Less important for a fan, since it is free turning and thus needs a little less power to get going. It's also a much smaller motor, maybe 80 watt or something...You'd still see the lights dim when you start a fan though...

Basically I wouldn't put much more load on it then lets say 400 watts. Then you keep a little bit of spare power to get your fan and television set going!

[nonthaburial]

Thanks people, you have all been a big help