What size inverter and batteries do I need?

Paul Michael

Subscriber
Hi Guys,

I have been going through my 2007 Damon Daybreak 3070 RV since I bought it last year replacing and adding to it.

One problem I still have is the Generac Generator still isn't working which is really annoying. (Cut's out once it warms up)

I have had it serviced by Mobile RV, called in Jason Kennedy, changed the temperature sensor and oil pressure sensor but couldn't sort it out, so as a last resort, . It was suggested that I contact Genplus in Scarborough as Andy Robson is the UK's Generac importer and expert.

I made a 470 mile round trip and drove to Scarborough to meet Andy and he couldn't sort the problem out and suggested that I get the generator taken out of the vehicle and delivered on a pallet to him so he can work on it on his bench. I explained that this is why I drove half way up the country so he could do it. He said that he really didn't want to take it out of the RV as it is a big job! ( wish he had told me that before my waste of time and money!!)

I now need to make the decision to let someone else look at it or scrap it and replace it but it's complicated as some of the appliances still work off 110v etc.

In the mean time, I need to replace the Ring 500w Inverter as it it rubbish. I don't think it is PSW as I have lines across the TV when trying to watch it and it is annoying.

My question to everyone is what size do I go for? I usually go mad and want the biggest and most expensive but what do I really need realistically?

I have 2 x 160w Solar panels but the batteries are old so I need to make sure I buy the correct batteries and Inverter.

Any suggestions welcome!

T.V.M.I.A.

Paul
 

bengie

Subscriber
had a 08 reg 3070 with a Generac generator nothing but problems was always breaking down cost me a small fortune. got rid of it in the end and purchased a new motorhome with Onan generator. a much better generator problem free.
 

sundowner

Subscriber
Hi
Are you talking about a 240to 110v ?? Or a 12 to 240 (or 12 to 110?)
We don't have the same issues as you as we are all 240v (no 110v)
We went for a 12to 240v inverter of 3kw we have 500 w of solar and two batteries giving 460 ah.
When the sun is shining we like to be able to make use of it, if we could have fitted bigger solar we would, so my answer is don't limit what you can do with the sun's power!!!! This is assuming you are not spending most of your time on EHU on campsites???
IMHO you can't have too much free electric!!!!!

We had a generac generator and although we had it looked at several times in the states it never would run without holding the start button, we still have it in the back of the shed ----- I am looking for a boat owner looking for an anchor!!!!!!
 
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Paul Michael

Subscriber
Hi
Are you talking about a 240to 110v ?? Or a 12 to 240 (or 12 to 110?)
We don't have the same issues as you as we are all 240v (no 110v)
We went for a 12to 240v inverter of 3kw we have 500 w of solar and two batteries giving 460 ah.
When the sun is shining we like to be able to make use of it, if we could have fitted bigger solar we would, so my answer is don't limit what you can do with the sun's power!!!! This is assuming you are not spending most of your time on EHU on campsites???
IMHO you can't have too much free electric!!!!!

We had a generac generator and although we had it looked at several times in the states it never would run without holding the start button, we still have it in the back of the shed ----- I am looking for a boat owner looking for an anchor!!!!!!
I'm looking for 12v to 240v so i can use my TV etc. from my batteries etc.

You should give Jason Kennedy a call, he may well sort your problem out and then you could sell it to me as a working genny! lol
 

Paul Michael

Subscriber
had a 08 reg 3070 with a Generac generator nothing but problems was always breaking down cost me a small fortune. got rid of it in the end and purchased a new motorhome with Onan generator. a much better generator problem free.
I have had approx 9 other RV's over the years and they all had Onan generators. Never had any problems at all. This Generac is a piece of garbage!
 

damon3272

Subscriber
Paul I have a 600watt modified sign inverter which runs the TV and Humax hard drive or DVD player perfectly no waves or snow on the TV,batteries I always use two 6Volt Trojan T105
 

motor roamin

Subscriber
Ring or PM Adi 4 I think he has a couple of onan gennies used in good condition he can also sort your inverter out with a new one Ring is absolute rubbish even for bulbs, well worth the trip to Adisorted all mine out (y)
 

Dodgey

Subscriber
Modern tv's etc do require pure sine wave, the difference is very noticeable. Our last rv, a 3070 also had a modified for the tv etc and worked but he was poor and having a sound bar and sub the sound was off. Replaced with a 600 watt psw and all perfect. I simply added up all the wattage of the at kit, tv, humax Freesat, sound bar and sub plus bluray player, rounded up and doubled it then looked at what was available, so 600 it was. Can't remember the make but eBay job, sturdy looking unit, decent reviews etc. Do remember to do the maths on cables though, often the cables supplied are barely up to the job and assume direct short distance connection to batteries.
 

sundowner

Subscriber
I forgot to say that our inverter is pure sign wave, so works everything on the van---- also our auto washing machine (on cold wash) or a little help with Genny on hot wash at the moment.
 

Paul Michael

Subscriber
Paul I have a 600watt modified sign inverter which runs the TV and Humax hard drive or DVD player perfectly no waves or snow on the TV,batteries I always use two 6Volt Trojan T105
Hi Colin.

I can't understand it, sorry!

I can see on eBay, some are saying 300w/600w or 1000w/2000w. So do i look at the first or second size i.e. 1000w or 2000w?

I have been reading on line and they are advising not to buy a modified sign wave inverter, but to get a Pure sign Wave inverter. Is that right?

Also, there seems to be a lot of 1000w PSW inverters for sale and they are cheap. Do you think one of these would be ok?

Thanks

Paul
 
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Olley

Subscriber
I have an 1800 watt modified sine wave inverter and its always powered everything without any problems, but it was an expensive Sterling model. PSW inverters now are much cheaper than they were 10 years ago so I would definitely say buy one of them over a MSW.

My general rule of thumb is not to take more than 20-25% in amps out of your batteries than there total capacity for any length time. So flat out my 1800watt inverter could take 180amps (another rule of thumb :)) so I need getting on for 640Ah in batteries but I only have 540Ah :(:) But apart from her hairdryer we never get near running it flat out. So I would say 2000watt or less should cover all your needs.
 

motor roamin

Subscriber
When it comes to inverters I would always buy Sterling not the cheapest or the dearest but good quality and never had a problem with one yet.

Just my opinion of course, just had Adi fit one to mine last time it was down at his place.
 

sundowner

Subscriber
The two figures quoted on inverters are AFAIK, the bigger number is for short bursts only, the lower number is for continual use, as Olly said, prices have come down so much I would only buy a PSW now as these will run everything within their amp rating.
I bought a cheap small PSW and it is crap, so l don't know how you can definitely be sure of good quality?????
We bought our 3 kw and also a 2 kw (for our cabin) from Sunshine solar in Norwich, I think the inverters will be swapped when we sell our van!!.
There are also more expensive ones available that will top up your EHU power and clever things like that!!!!!
I connected our van one to our EHU plug so we cannot mix mains power with the inverter (I know from experience that some inverters will not tolerate 240 v fed in the outlet connection!!!!!
This way of connection will power up all of the vans equipment and sockets, ( just remember to switch off the vans battery charger) so with enough sun/ battery we can heat the water, run the fridge etc etc. ---- the reason I say you cannot have too much solar/batteries!!!! And indeed enough inverter power to run bigger draw items like the hws, for months we have been using our electric kettle!!!! During the summer our gas kettle is redundant!!!!!!!
Nigel
 

Paul Michael

Subscriber
The two figures quoted on inverters are AFAIK, the bigger number is for short bursts only, the lower number is for continual use, as Olly said, prices have come down so much I would only buy a PSW now as these will run everything within their amp rating.
I bought a cheap small PSW and it is crap, so l don't know how you can definitely be sure of good quality?????
We bought our 3 kw and also a 2 kw (for our cabin) from Sunshine solar in Norwich, I think the inverters will be swapped when we sell our van!!.
There are also more expensive ones available that will top up your EHU power and clever things like that!!!!!
I connected our van one to our EHU plug so we cannot mix mains power with the inverter (I know from experience that some inverters will not tolerate 240 v fed in the outlet connection!!!!!
This way of connection will power up all of the vans equipment and sockets, ( just remember to switch off the vans battery charger) so with enough sun/ battery we can heat the water, run the fridge etc etc. ---- the reason I say you cannot have too much solar/batteries!!!! And indeed enough inverter power to run bigger draw items like the hws, for months we have been using our electric kettle!!!! During the summer our gas kettle is redundant!!!!!!!
Nigel
Thanks Nigel.

I will definitely get a PSW inverter and hopefully a good one. Some others on here have recommended Stirling so I will look at them. I am also thinking of buying 4 x Trojan T125's. Hopefully, that will keep me going with the 2 x 160w solar panels that I already have.

Thanks again for your help.

It's a learning curve!

Regards

Paul
 

tacr2man

Subscriber
I am running 880w of solar and four trojans T105 , that allows me to run a 230v domestic fridge freezer full time , and also running TV , and dvd player in evening , together with normal 12v lighting , and blowers etc , the lowest I have seen first thing in morning before solar cuts in is 90% full charge . Thats with PSW 2000w inverter . The solar is large but even in low levels of sunshine , it goes back to full charge very quickly , inc fridge at same time . HTSH .
 

damon3272

Subscriber
Hi Paul I got my modified 600watt inverter from Maplins about 4 years ago it had a two year warranty,I've had no problems at all I run a 32 inch TV no snow or lines at all,a 38inch sound bar with sub woofer and a humax box or dvd player all adds up to about 450 watts,the reason.I only had 600 watts is because it uses a lot less current on standby,I use the onboard genny for microwave hairdryer etc
 

Paul Michael

Subscriber
Hi Paul I got my modified 600watt inverter from Maplins about 4 years ago it had a two year warranty,I've had no problems at all I run a 32 inch TV no snow or lines at all,a 38inch sound bar with sub woofer and a humax box or dvd player all adds up to about 450 watts,the reason.I only had 600 watts is because it uses a lot less current on standby,I use the onboard genny for microwave hairdryer etc
I'm going to give Adi a visit it think. I still haven't got the genny working and hope he can sort it. Also, he might be able to weld some angle iron underneath so i can have 4 Trojans instead of two.
 
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