I need a reasonable sized (i.e. 1500 or 2000 watt) sine wave inverter
to use on our boat. I don't want to pay silly over the odds prices
but on the other hand I do want one that works to specification.

The problem is that many eBay/Chinese suppliers play the same game as
amplifier makers used to so that a nominal (say) 1000 watt inverter
actually says in the description that it can't supply 1000 watts
continuously. Reading the very few reviews one can find shows that in
many cases the reality is that inverters can't supply anywhere near
their rated output.

However, on the other hand, there are excellent inverters available at
very reasonable prices. The inverter I currently have is a nominal
500 watt one that cost me £25 back in 2012 and it copes admirably with
just about everything I throw at it plus giving up gracefully when I
ask too much. Among other things it runs an ordinary domestic
refrigerator without problems and fridges are supposedly one of the
more difficult loads for inverters.

The 500 watt inverter is a 'modified sine wave' one, I want a the
larger, sine wave one to run a microwave among other things.

So how do I find a supplier as good as the one who made my old 500
watt inverter? I can't take a look at it just now but I suppose that
might be one approach, get another from the same manufacturer if they
make 'pure sine' inverters. However any other recommendations of good
suppliers or other ways to find good manufacturers would be most
welcome.

--
Chris Green
·

There used to be low voltage Microwaves a few years back. I don't know how
the very high voltages were created for the Magnetron, but I suspect this
might be more efficiently done at 400 hz with a smaller transformer than
attempting to feed an inefficient mains one from an invertors unless you
have half the boat rigged up as batteries that is!
Brian

--
----- -
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please!
"Chris Green" wrote in message
...
I need a reasonable sized (i.e. 1500 or 2000 watt) sine wave inverter
to use on our boat. I don't want to pay silly over the odds prices
but on the other hand I do want one that works to specification.

The problem is that many eBay/Chinese suppliers play the same game as
amplifier makers used to so that a nominal (say) 1000 watt inverter
actually says in the description that it can't supply 1000 watts
continuously. Reading the very few reviews one can find shows that in
many cases the reality is that inverters can't supply anywhere near
their rated output.

However, on the other hand, there are excellent inverters available at
very reasonable prices. The inverter I currently have is a nominal
500 watt one that cost me £25 back in 2012 and it copes admirably with
just about everything I throw at it plus giving up gracefully when I
ask too much. Among other things it runs an ordinary domestic
refrigerator without problems and fridges are supposedly one of the
more difficult loads for inverters.

The 500 watt inverter is a 'modified sine wave' one, I want a the
larger, sine wave one to run a microwave among other things.

So how do I find a supplier as good as the one who made my old 500
watt inverter? I can't take a look at it just now but I suppose that
might be one approach, get another from the same manufacturer if they
make 'pure sine' inverters. However any other recommendations of good
suppliers or other ways to find good manufacturers would be most
welcome.

--
Chris Green
·

Brian Gaff wrote:
There used to be low voltage Microwaves a few years back. I don't know how
the very high voltages were created for the Magnetron, but I suspect this
might be more efficiently done at 400 hz with a smaller transformer than
attempting to feed an inefficient mains one from an invertors unless you
have half the boat rigged up as batteries that is!

Yes, I did search for '12v microwave' but all it brought up was
combined purchases of a mains microwave and an inverter. Since we
have the microwave already this seems not to be a very useful
approach.

--
Chris Green
·

On Fri, 14 Jul 2017 16:00:50 +0100, Chris Green wrote:

The 500 watt inverter is a 'modified sine wave' one, I want a the
larger, sine wave one to run a microwave among other things.

Might be better to look at 12 or 24 V microwaves designed for
truckers. removes an energy conversion stage if nothing else. And
judging by how the lights dip when the magnatron fires up in our
microwave it has a hefty switch on surge. That might give an invertor
problems.

Would a normal mains microwave object to a modified sine wave
invertor anyway? IIRC that just means the wave form is a series of
steps up/down rather than a single square wave as the really cheapy
ones use.

--
Cheers
Dave.

On Friday, 14 July 2017 16:03:07 UTC+1, Chris Green wrote:
I need a reasonable sized (i.e. 1500 or 2000 watt) sine wave inverter
to use on our boat. I don't want to pay silly over the odds prices
but on the other hand I do want one that works to specification.

The problem is that many eBay/Chinese suppliers play the same game as
amplifier makers used to so that a nominal (say) 1000 watt inverter
actually says in the description that it can't supply 1000 watts
continuously. Reading the very few reviews one can find shows that in
many cases the reality is that inverters can't supply anywhere near
their rated output.

However, on the other hand, there are excellent inverters available at
very reasonable prices. The inverter I currently have is a nominal
500 watt one that cost me £25 back in 2012 and it copes admirably with
just about everything I throw at it plus giving up gracefully when I
ask too much. Among other things it runs an ordinary domestic
refrigerator without problems and fridges are supposedly one of the
more difficult loads for inverters.

The 500 watt inverter is a 'modified sine wave' one, I want a the
larger, sine wave one to run a microwave among other things.

So how do I find a supplier as good as the one who made my old 500
watt inverter? I can't take a look at it just now but I suppose that
might be one approach, get another from the same manufacturer if they
make 'pure sine' inverters. However any other recommendations of good
suppliers or other ways to find good manufacturers would be most
welcome.

--
Chris Green
·

They had them in Machine Mart.
https://www.machinemart.co.uk/c/power-inverters/

On Friday, 14 July 2017 16:03:07 UTC+1, Chris Green wrote:
I need a reasonable sized (i.e. 1500 or 2000 watt) sine wave inverter
to use on our boat. I don't want to pay silly over the odds prices
but on the other hand I do want one that works to specification.

The problem is that many eBay/Chinese suppliers play the same game as
amplifier makers used to so that a nominal (say) 1000 watt inverter
actually says in the description that it can't supply 1000 watts
continuously. Reading the very few reviews one can find shows that in
many cases the reality is that inverters can't supply anywhere near
their rated output.

However, on the other hand, there are excellent inverters available at
very reasonable prices. The inverter I currently have is a nominal
500 watt one that cost me £25 back in 2012 and it copes admirably with
just about everything I throw at it plus giving up gracefully when I
ask too much. Among other things it runs an ordinary domestic
refrigerator without problems and fridges are supposedly one of the
more difficult loads for inverters.

The 500 watt inverter is a 'modified sine wave' one, I want a the
larger, sine wave one to run a microwave among other things.

So how do I find a supplier as good as the one who made my old 500
watt inverter? I can't take a look at it just now but I suppose that
might be one approach, get another from the same manufacturer if they
make 'pure sine' inverters. However any other recommendations of good
suppliers or other ways to find good manufacturers would be most
welcome.

--
Chris Green
·

https://www.google.co.uk/search?q=ma...vens+for+boats

On 14/07/2017 16:00, Chris Green wrote:
I need a reasonable sized (i.e. 1500 or 2000 watt) sine wave inverter
to use on our boat. I don't want to pay silly over the odds prices
but on the other hand I do want one that works to specification.


Numax 2kW true sine from Tayna (or elsewhere) about £350. I have several
and they are fine. I don't know if they do 24V ones though.

Have you thought about splitting the load and using two or more?

Bill

On 14/07/2017 16:48, Chris Green wrote:
Brian Gaff wrote:
There used to be low voltage Microwaves a few years back. I don't know how
the very high voltages were created for the Magnetron, but I suspect this
might be more efficiently done at 400 hz with a smaller transformer than
attempting to feed an inefficient mains one from an invertors unless you
have half the boat rigged up as batteries that is!

Yes, I did search for '12v microwave' but all it brought up was
combined purchases of a mains microwave and an inverter. Since we
have the microwave already this seems not to be a very useful
approach.


I have a 24V Waeco microwave and it's fine. Had it since 2001. It was
mighty pricey though. Pulls about 40A.

Bill

On Friday, 14 July 2017 16:03:07 UTC+1, Chris Green wrote:
I need a reasonable sized (i.e. 1500 or 2000 watt) sine wave inverter
to use on our boat. I don't want to pay silly over the odds prices
but on the other hand I do want one that works to specification.

The problem is that many eBay/Chinese suppliers play the same game as
amplifier makers used to so that a nominal (say) 1000 watt inverter
actually says in the description that it can't supply 1000 watts
continuously. Reading the very few reviews one can find shows that in
many cases the reality is that inverters can't supply anywhere near
their rated output.

However, on the other hand, there are excellent inverters available at
very reasonable prices. The inverter I currently have is a nominal
500 watt one that cost me £25 back in 2012 and it copes admirably with
just about everything I throw at it plus giving up gracefully when I
ask too much. Among other things it runs an ordinary domestic
refrigerator without problems and fridges are supposedly one of the
more difficult loads for inverters.

The 500 watt inverter is a 'modified sine wave' one, I want a the
larger, sine wave one to run a microwave among other things.

So how do I find a supplier as good as the one who made my old 500
watt inverter? I can't take a look at it just now but I suppose that
might be one approach, get another from the same manufacturer if they
make 'pure sine' inverters. However any other recommendations of good
suppliers or other ways to find good manufacturers would be most
welcome.

If you want cheap I suppose you could use a MOT and a vibrator. No, not that type.


NT

Bill Wright wrote:
On 14/07/2017 16:48, Chris Green wrote:
Brian Gaff wrote:
There used to be low voltage Microwaves a few years back. I don't know how
the very high voltages were created for the Magnetron, but I suspect this
might be more efficiently done at 400 hz with a smaller transformer than
attempting to feed an inefficient mains one from an invertors unless you
have half the boat rigged up as batteries that is!

Yes, I did search for '12v microwave' but all it brought up was
combined purchases of a mains microwave and an inverter. Since we
have the microwave already this seems not to be a very useful
approach.


I have a 24V Waeco microwave and it's fine. Had it since 2001. It was
mighty pricey though. Pulls about 40A.

Yes, it will take a lot of current whether separate inverter plus
mains microwave or 'integrated' 12 volt microwave. We have something
like 400Ah of 12 volt battery capacity on the boat and three 260 watt
solar panels keeping them charged.

--
Chris Green
·

Dave Liquorice wrote:
On Fri, 14 Jul 2017 16:00:50 +0100, Chris Green wrote:

The 500 watt inverter is a 'modified sine wave' one, I want a the
larger, sine wave one to run a microwave among other things.

Might be better to look at 12 or 24 V microwaves designed for
truckers. removes an energy conversion stage if nothing else. And
judging by how the lights dip when the magnatron fires up in our
microwave it has a hefty switch on surge. That might give an invertor
problems.

Yes, if I could actually find anyone selling such a thing it would be
ideal but no one seems to make them any more. Searching just produces
'no longer available' or eBay sales of several years ago.


Would a normal mains microwave object to a modified sine wave
invertor anyway? IIRC that just means the wave form is a series of
steps up/down rather than a single square wave as the really cheapy
ones use.

Well according to what I have managed to read about it a microwave
will run on modified sine wave but runs quieter, better *and* more
efficiently on pure sine wave.

--
Chris Green
·

harry wrote:
On Friday, 14 July 2017 16:03:07 UTC+1, Chris Green wrote:
I need a reasonable sized (i.e. 1500 or 2000 watt) sine wave inverter
to use on our boat. I don't want to pay silly over the odds prices
but on the other hand I do want one that works to specification.

The problem is that many eBay/Chinese suppliers play the same game as
amplifier makers used to so that a nominal (say) 1000 watt inverter
actually says in the description that it can't supply 1000 watts
continuously. Reading the very few reviews one can find shows that in
many cases the reality is that inverters can't supply anywhere near
their rated output.

However, on the other hand, there are excellent inverters available at
very reasonable prices. The inverter I currently have is a nominal
500 watt one that cost me £25 back in 2012 and it copes admirably with
just about everything I throw at it plus giving up gracefully when I
ask too much. Among other things it runs an ordinary domestic
refrigerator without problems and fridges are supposedly one of the
more difficult loads for inverters.

The 500 watt inverter is a 'modified sine wave' one, I want a the
larger, sine wave one to run a microwave among other things.

So how do I find a supplier as good as the one who made my old 500
watt inverter? I can't take a look at it just now but I suppose that
might be one approach, get another from the same manufacturer if they
make 'pure sine' inverters. However any other recommendations of good
suppliers or other ways to find good manufacturers would be most
welcome.

--
Chris Green
·

They had them in Machine Mart.
https://www.machinemart.co.uk/c/power-inverters/

Yes, but *much* more expensive than you can find on eBay, aliexpress,
etc. I'm trying to work out how to find a reliable eBay one.

--
Chris Green
·

Bill Wright wrote:
On 14/07/2017 16:00, Chris Green wrote:
I need a reasonable sized (i.e. 1500 or 2000 watt) sine wave inverter
to use on our boat. I don't want to pay silly over the odds prices
but on the other hand I do want one that works to specification.


Numax 2kW true sine from Tayna (or elsewhere) about £350. I have several
and they are fine. I don't know if they do 24V ones though.

2kw sine wave inverters start at around a third of that price, I've
found quite a few around £105 to £150. I just want to try and find a
reliable supplier among the many in this price range, I'm sure there
are some.


Have you thought about splitting the load and using two or more?

It's a possibility though it makes life a bit complicated on the boat
as some of the time we have mains power from the marina so then things
like the microwave would be plugged into normal sockets.

--
Chris Green
·

Chris Green wrote:
I need a reasonable sized (i.e. 1500 or 2000 watt) sine wave inverter
to use on our boat. I don't want to pay silly over the odds prices
but on the other hand I do want one that works to specification.

The problem is that many eBay/Chinese suppliers play the same game as
amplifier makers used to so that a nominal (say) 1000 watt inverter
actually says in the description that it can't supply 1000 watts
continuously. Reading the very few reviews one can find shows that in
many cases the reality is that inverters can't supply anywhere near
their rated output.

However, on the other hand, there are excellent inverters available at
very reasonable prices. The inverter I currently have is a nominal
500 watt one that cost me £25 back in 2012 and it copes admirably with
just about everything I throw at it plus giving up gracefully when I
ask too much. Among other things it runs an ordinary domestic
refrigerator without problems and fridges are supposedly one of the
more difficult loads for inverters.

The 500 watt inverter is a 'modified sine wave' one, I want a the
larger, sine wave one to run a microwave among other things.

So how do I find a supplier as good as the one who made my old 500
watt inverter? I can't take a look at it just now but I suppose that
might be one approach, get another from the same manufacturer if they
make 'pure sine' inverters. However any other recommendations of good
suppliers or other ways to find good manufacturers would be most
welcome.

VICTRON inverters and chargers are excellent performers and built like
brick outhouses.

Bob Minchin wrote:
Chris Green wrote:
I need a reasonable sized (i.e. 1500 or 2000 watt) sine wave inverter
to use on our boat. I don't want to pay silly over the odds prices
but on the other hand I do want one that works to specification.

The problem is that many eBay/Chinese suppliers play the same game as
amplifier makers used to so that a nominal (say) 1000 watt inverter
actually says in the description that it can't supply 1000 watts
continuously. Reading the very few reviews one can find shows that in
many cases the reality is that inverters can't supply anywhere near
their rated output.

However, on the other hand, there are excellent inverters available at
very reasonable prices. The inverter I currently have is a nominal
500 watt one that cost me £25 back in 2012 and it copes admirably with
just about everything I throw at it plus giving up gracefully when I
ask too much. Among other things it runs an ordinary domestic
refrigerator without problems and fridges are supposedly one of the
more difficult loads for inverters.

The 500 watt inverter is a 'modified sine wave' one, I want a the
larger, sine wave one to run a microwave among other things.

So how do I find a supplier as good as the one who made my old 500
watt inverter? I can't take a look at it just now but I suppose that
might be one approach, get another from the same manufacturer if they
make 'pure sine' inverters. However any other recommendations of good
suppliers or other ways to find good manufacturers would be most
welcome.

VICTRON inverters and chargers are excellent performers and built like
brick outhouses.

... and cost an arm and a leg to buy. Not to mention that if they *do*
go wrong they are so full of proprietary hardware and software that an
expensive engineer call-out is almost always necessary.

--
Chris Green
·

On Fri, 14 Jul 2017 18:34:45 +0100, Chris Green wrote:

Have you thought about splitting the load and using two or more?

It's a possibility though it makes life a bit complicated on the boat
as some of the time we have mains power from the marina so then things
like the microwave would be plugged into normal sockets.

A few break before make double pole change over (or three position)
switches would sort that out.

--
Cheers
Dave.

On Fri, 14 Jul 2017 18:27:46 +0100, Chris Green wrote:

Might be better to look at 12 or 24 V microwaves designed for
truckers. removes an energy conversion stage if nothing else.

Yes, if I could actually find anyone selling such a thing it would be
ideal but no one seems to make them any more. Searching just produces
'no longer available' or eBay sales of several years ago.

Odd, google "truck microwave" produces a number of companies selling
24 V microwaves that appear to be available. The best part of 40 A
that an 800 W output 24 V microwave will draw means some hefty bits
of connecting string. B-)

--
Cheers
Dave.

On Saturday, 15 July 2017 23:26:12 UTC+1, Dave Liquorice wrote:
Odd, google "truck microwave" produces a number of companies selling
24 V microwaves that appear to be available. The best part of 40 A
that an 800 W output 24 V microwave will draw means some hefty bits
of connecting string.

No heftier than an electric shower, so you could use 6mm over short distances subject to mounting method.

And of course you save the standby consumption of the inverter running down your battery.

Owain

Dave Liquorice wrote:
On Fri, 14 Jul 2017 18:34:45 +0100, Chris Green wrote:

Have you thought about splitting the load and using two or more?

It's a possibility though it makes life a bit complicated on the boat
as some of the time we have mains power from the marina so then things
like the microwave would be plugged into normal sockets.

A few break before make double pole change over (or three position)
switches would sort that out.

Yes, but you still have to change them to the right position every
time you swap things around from 'big inverter' to 'small inverter' to
'shore power', etc. As it is with just one inverter we quite often
forget to switch back to shore power when we plug in. It could be
automated of course but not (easily) if we have more than one inverter.

--
Chris Green
·