Pure (True) vs. Modified Sine Wave?

[Turtuga Blanku]

Hi,doe's anyone know if I can run a well pump of a modified sine wave inverter,without it harming the pumps motor?

as far as I know, yes. Be sure to use a expansion "barrel" (can't find the right english word at the mo) so that the pump to not go on-off-on-off when you use it for your toilet or something.. THAT will kill your pump possibly within just a couple of months.

[Clara]

I have a 300w inverter,I brought 20 years ago.Its heavy,noisy and draws 5 amps with no load,attached.I assume it must be a PSW as I never had any problems but I haven't used it much due to it's inefficiency.I would guess modern PSW inverters are far more efficient.

not necessarily so....the 1000w MSW invertor that we replaced ran everything fine, the new one blew stuff up!

[ENIGMA]

Clara,the word you are looking for is "pressure tank" and yes I do have one.

I've done some searches on the web and it seems a MSW inverter will be ok for an electric pump,so I will give it a try. 600w MSW inverter with a 1200w surge for 40 pound. http://www.mdsbattery.co.uk The equivalent PSW inverter would cost nearer 100 pound.

Why did you replace your 1000w MSW inverter,if it ran everything fine?

[andyt]

I would guess that something pulling 5amps offload is due for the re-cycling bin!!

[Clara]

Why did you replace your 1000w MSW inverter,if it ran everything fine?

Good question! We upgraded the whole system and we decided that we would prefer to run power tools off the PV too, as opposed to the generator (we are entirely off-grid).
A very knowledgeable friend of mine (with a 5KW invertor that he picked up off ebay ) also points out to me that the less you tax your invertor, the longer it will last (something to do with the components not overheating). He´s the sort of (German) guy to be right about these things, and do things very properly, so I trust him.

[romany123]

Enigma
I also have a well in my garden. It has all the original parts but I am having problems finding a leather cup seal to enable me to hand pump it (if anybody knows where I can obtain these, it would be appreciated).
Instead of using an inverter for your 240v pump, why not use a 12 V boat bilge pump? I have one and if I can't get the well to work by hand I will use that.

[ENIGMA]

Hi Dave,have you thought about making a seal for your pump from leather and grease or rubber?
Interesting what you said about a 12v bilge pump,but unfortunately they all appear to be submersible types,which I can't use due to not having direct access to the well.I would also imagine the pressure would not be sufficient.

Incidentally,I know Brightlingsea well,I have been sailing there many times.

[romany123]

Good morning Enigma

I have tried ruber seals (Part of a loo bend kit) to no avail.

Apparently the leather has got to be moulded otherwise the stitching wears through. There were originally leather seals on the pump I believe. As you quite rightly say, have probably had grease spread around them to make a good seal.

I understand what you're saying about the 12 V lift pump, you are quite right mine is a submersible and can reach ahead of about 5 m. But I am loath to use it until I have exhausted all other possibilities.

I been sailing into Brightlingsea for many years before I moved here. My boat is moored not too far away in Walton-on-naze. Great sailing area