Has anyone "actualy" had problems with "a good quality modified sinewave inverte

Have been using a modified sine wave inverter in our caravan for a few years now and have had no problems at all regards charging mobile phone, running small appliances and a small domestic freezer. I believe some appliances eg computers etc may need a pure sine wave but I have personally had no problems with anything else. You mention a 500w inverter to run a small fridge/freezer, I don't believe this will be big enough as you will need at least over a 1000w to start it. I have tried to start a domestic freezer with 1000w inverter and the relay will just keep clicking with not enough power to start it. I have installed a 2000w in our van and it will start and run a small domestic freezer, vacuum cleaner and any other appliance in the van with the exception of the air conditioner. You should be able to pick up a 2000w inverter for around $600.
Regards Foxhound (WA)

The freezer I mentioned above is a 60 litre Mistral domestic chest freezer. A 1300w Robin Generator will start it only just providing the freezer has not been running for awhile and there is no pressure build up in the compressor. I would say without a doubt it would not start with 1000w inverter but the 2000w does it with ease. The 2000w inverter I have is a Protector brand (I think) and I purchased it from Repco a few years back for $500 on special. The unit is about 450mm long x about 250mm wide and about 100mm in depth connected by heavy duty battery cable to two 130amp hour Trojan deep cycle batteries. I can actually run the freezer on 240v while we travel with the vehicle charging the batteries via an anderson plug. To run an inverter of this size you will need a reasonable battery power supply as the inverter itself does use some power when on standby mode. Hope this has been of some help.
Regards Foxhound (WA)

Never had a problem

Check out thread 63748, pretty much answers your questions.

Jim.

I have. 400w good quality MSW inverter refuses to run 180W PS for laptop. No-one can answer you on this question in full – you have to try. Generally more load going to passive end less likely you will have any problem. Thus things like irons and tungsten bulb 100% proven; motors usually OK. Most problematic switch-mode PS (commonly found in laptops nowadays) and especially devices that relays on sine form to work properly – best examples tyristor controllers of different kind, i.e. dimmers and variable speed AC motors found in some appliances like drills. You have to try it to found.

Cheers
Serg

G N

I have a 70L Mistral freezer modified to operate as a refrigerator in my motorhome. A Jaycar Powertech 500watt "pure sine wave inverter" and it will JUST start it reliably with nothing else connected. It and the fridge run almost silently. I tried the same brand 600watt modified square wave version but it would not start the freezer and shut down. A Powertech 1000watt modified square wave model easily started it but the compressor motor made such growling sounds while running that is was immediately very apparent that damage was going to occur and we would never have a good night’s sleep (-: