Faulty Inverter ???

[sibs]

We purchsed our 2005 HymerCampGT. We are hoping to go travelling for a few months in Europe next year, wild camping and EHU.
After having problems with our leisure batteries, we have replaced all 4 of them, and also new engine battery. Our van has a PowerSource 2100
Rinv2100 inverter. We suspect that it isnt working to its full capacity. The reason for thinking this is
1. Travel kettle works (250-1000w) but alot slower than when on EHU.
2. Toaster heats up but you have to manually hold the buton down that keeps the toast down - works properly when on EHU.
3.45w cooling fan makes a noise but isnt giving out any cool air - works fine on EHU
4. 1200w hair dryer appears to be working okay but i only ran it for a few seconds.
We have got the van booked in @ the end of the month to have inverter tested.
Here is where i need help, the inverter is approx 10-12 yers old, it is working but not to full capacity ( ithink). Can it be repaired???
If not, would i get away with a smaller inverter taking into account the appliances mentioned above. Do we buy pure sine or modified?
I have found several Stirling units @ a reasonable price i think £300-350. But have also seen a lot way cheaper on Ebay.
Thoughts please

 

[funflair]

Is the one you have now modified or pure sine, if modified I think that explains the poor performance, I would go pure every time.

 

[Stealaway]

You are asking far too much from your batteries --- and inverter. 1000watt element will pull over 100amp from your batteries while ever it's connected.
Not long before you've completely flattened them

 

[sibs]

the inverter we have at the moment is a modified sine. I suspect that it has worked fine for the last
10years. The size of it explains why we have 4 leisure batteries to run it. But the question is do we
need such a big inverter, if not what size would we get away with??

 

[hymerman]

You are asking far too much from your batteries --- and inverter. 1000watt element will pull over 100amp from your batteries while ever it's connected.
Not long before you've completely flattened them

I agree with Stealaway.
Also check the size of the cable from the batteries to the inverter, you are pulling a massive current and could overheat them, they could be the cause of your problems if they aren't substantial enough.
You have 20 times the current going into the inverter from the 12v batteries as is coming out on 240v.
Power is volts x amps
The batteries also need to be close together and not far from the inverter to avoid any possible voltage drops

^{_{Subscribers  do not see these advertisements}}

 

[sibs]

This is the set up that came with the van, it was all done when the van was new in 2005. All works done by Vanbitz so im sure cabling etc are as they should be. Any ideas on what size of inverter i would need, obviously will only be running one of the mentioned appliances at any given time.

 

[Robert Clark]

This is the set up that came with the van, it was all done when the van was new in 2005. All works done by Vanbitz so im sure cabling etc are as they should be. Any ideas on what size of inverter i would need, obviously will only be running one of the mentioned appliances at any given time.

Cabling size is dependent on which size inverter you have.
Our 2kw Victron specified 70mm cable from the battery

 

[DBK]

If you can check the output voltage when under load it might reveal something. It sounds as if it maybe low which suggests either a defect or the cables are too thin. We have a 1500W pure sine and it runs a coffee machine and a hair dryer perfectly - but they are only used for short periods. I wouldn't use it to run a kettle, that's what gas is for.

 

[Kannon Fodda]

You have replaced your batteries. Are they exact match for the original or something different. If different they may in total no longer support the current draw of the originals.

Worth looking closely at all connections. Is there good electrical contact on all the batteries and all leads linking them and the inverter. Even if you reused all the cabling from the earlier install, at the current draw you need even a slight voltage drop from poor resistance would cause problems.

 

[dunnah01]

I'd be looking at the cheapo 1500/3000W pure sine waves off fleebay. I bought a 3000/6000W version and it works fine for dumb electrical things (hair dryer, iron, hoover) although it's a bit erratic for more precious electrical items (laptop charges but mouse doesn't work, tooth brushes & shaver only charge about 75%)

^{_{Subscribers  do not see these advertisements}}

 

[Raul]

the inverter we have at the moment is a modified sine. I suspect that it has worked fine for the last
10years. The size of it explains why we have 4 leisure batteries to run it. But the question is do we
need such a big inverter, if not what size would we get away with??

Only you can answer that, what loads you have and what is the biggest load ( peak power), that will dictate the size of inverter. Then you will need to size the cables according to load and distance. Then you size the battery capacity to cover the inverter load at a rate that is in line with the battery spec.

 

[sibs]

Sorry but we are new to this and assumed that the use of such a large inverter along with 4 leisure batteries
was to enable the use of kettles, hairdryers etc without any issues. The 4 batteries and inverter were all done by vanbitz in cornwall and from what ive read they know there stuff when it comes to electrics on motorhomes. If they werent located 600 miles away from us i would have no qualms in taking it to them

 

[dunnah01]

Sorry but we are new to this and assumed that the use of such a large inverter along with 4 leisure batteries
was to enable the use of kettles, hairdryers etc without any issues. The 4 batteries and inverter were all done by vanbitz in cornwall and from what ive read they know there stuff when it comes to electrics on motorhomes. If they werent located 600 miles away from us i would have no qualms in taking it to them

The setup should be fine if you have the means to refill the batteries

 

[sibs]

Only you can answer that, what loads you have and what is the biggest load ( peak power), that will dictate the size of inverter. Then you will need to size the cables according to load and distance. Then you size the battery capacity to cover the inverter load at a rate that is in line with the battery spec.

ooh that all sounds very technical, i just want to be able to use any of the low wattage appliances i mentioned
above, but thank you for your thoughts

 

[sibs]

The setup should be fine if you have the means to refill the batteries

We also have 2 x 75 watt solar panels and a stirling B2B thingy

^{_{Subscribers  do not see these advertisements}}

 

[Raul]

Assuming your batteries are healthy and can deliver the amps the inverter is asking, any inverter will derate or reduce its power output when is hot, well above 30 degC. Other reason for derating is DC high ripple, this will reduce the power temporarily to catch up with the voltage drop. This can be caused by undersized cables, bad connections, weak battery or undersized for its discharge rate. Other than that I haven’t come across of inverter derating and it should work at it’s full output.

 

[Kannon Fodda]

Sorry but we are new to this and assumed that the use of such a large inverter along with 4 leisure batteries
was to enable the use of kettles, hairdryers etc without any issues. The 4 batteries and inverter were all done by vanbitz in cornwall and from what ive read they know there stuff when it comes to electrics on motorhomes. If they werent located 600 miles away from us i would have no qualms in taking it to them

It will have been up to the mark when originally done, your first post suggests 2005. A lot can change over the years. You've said you replaced batteries, see my comment above if they aren't like for like. The quality of wiring may no longer offer the same degree of electrical continuity, check and remake everything. But electrical devices themselves may degrade so the inverter may have lost some efficiency or simply has developed a fault from age.

Appliances like kettles and hairdryers, are high wattage and need a lot of battery capacity. The setup may have been OK, when installed, but within certain parameters to avoid taking too much from the batteries. You only have a certain capacity and so individual operation shouldn't be for too long a duration, and repeated use of kettles, hairdryers, etc must be limited to within the limits of your battery storage and recharge capability. 2x75W solar would take a long time to put the power back in and even the B2B will need you to be driving some time if you've run down 4 batteries.

 

[dunnah01]

We also have 2 x 75 watt solar panels and a stirling B2B thingy

2x75w solar really isn't enough at this time of year. I've got 2x180W and they barely cope with the current cr@ppy weather. The B2B may give up some of your juice to the starter battery so doesn't help unless you're doing good miles to charge the leisure batteries from the engine alternator. It may he worth looking at more solar and more days on EHU to fully charge the battery bank every few days

 

[sibs]

You have replaced your batteries. Are they exact match for the original or something different. If different they may in total no longer support the current draw of the originals.

Worth looking closely at all connections. Is there good electrical contact on all the batteries and all leads linking them and the inverter. Even if you reused all the cabling from the earlier install, at the current draw you need even a slight voltage drop from poor resistance would cause problems.

Thank you for that, it sounds like its worth looking into. When we had the batteries replaced, they were replaced with like for like batteries, but when the van goes back in at the end of the month i will get him to double check all connections

 

[DBK]

Thank you for that, it sounds like its worth looking into. When we had the batteries replaced, they were replaced with like for like batteries, but when the van goes back in at the end of the month i will get him to double check all connections

Are you sure the batteries are fully charged? Do you have a meter in the MH which shows the battery voltage? We only have two 90Ah batteries and they run the hairdryer and coffee machine without problems so I don't think battery capacity is your issue - assuming they are fully charged of course.

^{_{Subscribers  do not see these advertisements}}

 

[autorouter]

If the biggest load is 1200W, and you are happy with only running one appliance at a time, I'd say a 1500W inverter will be OK. The kettle and hairdryer will probably be fine on a modified sine wave type, but other things, especially with digital controls like a coffeemaker or microwave, will probably need pure sine wave. So, take a chance with cheaper MSW, or peace of mind with more expensive PSW - your call, I'm afraid.

I had a 2000W MSW inverter that wouldn't run the 1200W coffeemaker, and was very poor with the 700W microwave. I now have a PSW inverter which runs everything fine.

The battery current at 1500W will be 1500/12 = 125A. With 4 batteries that's 31A per battery, which is OK - a bit high for continuous use, but it will probably be in short bursts anyway.

 

[two]

I think you need a 1200W pure sine wave inverter, to run the hairdryer. 1500W would be better.
Whatever you do, do not use the inverter for a kettle. Use gas.
If you could abandon the hairdryer, you could get away with much less but I understand the benefit of a stable marriage.
Even though you have a good size battery bank, they don't like heavy discharges, so try to use the hairdryer as little a possible and give the batteries a longer life. It's not like being at home (unless on EHU).

 

[sibs]

I think you need a 1200W pure sine wave inverter, to run the hairdryer. 1500W would be better.
Whatever you do, do not use the inverter for a kettle. Use gas.
If you could abandon the hairdryer, you could get away with much less but I understand the benefit of a stable marriage.
Even though you have a good size battery bank, they don't like heavy discharges, so try to use the hairdryer as little a possible and give the batteries a longer life. It's not like being at home (unless on EHU).

Thank you, that is very helpful. heating up water in a pot is an easy fix, limited use of hair dryer is also doable. What about the toaster it is only 700 w and what are your thoughts on cheap inverters please

 

[sibs]

Are you sure the batteries are fully charged? Do you have a meter in the MH which shows the battery voltage? We only have two 90Ah batteries and they run the hairdryer and coffee machine without problems so I don't think battery capacity is your issue - assuming they are fully charged of course.

The onboard display shows that batteries are fully charged, we have 4 x 115Ah batteries, what size of inverter do you have

 

[funflair]

I'd be looking at the cheapo 1500/3000W pure sine waves off fleebay. I bought a 3000/6000W version and it works fine for dumb electrical things (hair dryer, iron, hoover) although it's a bit erratic for more precious electrical items (laptop charges but mouse doesn't work, tooth brushes & shaver only charge about 75%)

Why would you go cheapo "pure sine" when you admit that it doesn't work very well?

^{_{Subscribers  do not see these advertisements}}

 

[DBK]

Thank you, that is very helpful. heating up water in a pot is an easy fix, limited use of hair dryer is also doable. What about the toaster it is only 700 w and what are your thoughts on cheap inverters please

The toaster should work unless it is something fancy with electronics in it. If it is a basic toaster but isn't working other than as a bread warmer I suggest you need to find a mobile vehicle electrician to diagnose the fault if you don't think you have the skills or kit to do it yourself. Because it should be working given your description of the setup which suggests there is a fault somewhere. However, I suggest checking the batteries are fully charged first.

 

[Raul]

If 1200w is your max, I can recommend a Victron 12/1200 Phoenix: for about 375 quid, or look for second hand Victron or Studer. Don’t be put of by being pre owned, these two will work they arse off for many years.

 

[DBK]

The onboard display shows that batteries are fully charged, we have 4 x 115Ah batteries, what size of inverter do you have

Sorry missed this post. Our inverter is 1500W and is what is described as a "cheapie" but it has done well for at least a couple of years. I don't think you have a capacity problem, there's something else going on. For example in your first post you said it couldn't run a 45W fan - that's not right. It should be able to do that without breaking into a sweat.

 

[dunnah01]

Why would you go cheapo "pure sine" when you admit that it doesn't work very well?

It's for making toast not clever stuff

 

[funflair]

ooh that all sounds very technical, i just want to be able to use any of the low wattage appliances i mentioned
above, but thank you for your thoughts

You can use anything you like, BUT you will be limited by what your batteries can supply and then you need to understand how you are going to replace the power you have just used so you can do it again and again and again otherwise you will end up with at the best flat batteries or at the worst ruined batteries, the simple formula is Watts=VoltsxAmps so 1000W/12V=83A do that for 6 minutes and it about 9ah with inverter losses.

^{_{Subscribers  do not see these advertisements}}