Battery charging Forums

BarryandSue

Er, would an Ever-Ready PP9 help?

Sorry, chaps, I lost it there! What's really needed for dopes like me, is not so much a collection of electrical [u:aa3f19d465]products[/u:aa3f19d465] available, but a choice of [u:aa3f19d465]answers[/u:aa3f19d465]. For example, if I want to do such-and-such with my motorhome, I want someone to tell me that I will need "one of these" and "two of those" fitted, and sell me the whole set-up. Full stop.

The parts, including correct wiring, fuses, and full instructions, would get someone started, whereas at the moment, I believe a lot of people buy [u:aa3f19d465]nothing[/u:aa3f19d465] because the alternative is to take a degree in electronics, or hand over their next six months wages to have someone else do it for them.

Many people are able to follow straightforward instructions, so could upgrade their basic system to something that is worthwhile, but they aren't able to make a sensible decision through sheer lack of knowledge. All they need is a businessman to offer a "package". So, Ben, "business opportunity" here! Perhaps offer two or three, basic, "upgrade" sytems for self-fit?

Me? I'm too frightened to do anything until you do! Shocked

Barry

Anonymous

DABurleigh, the good news is that the EU10i does have sufficient output to work with PowerAssist, and charge at nearly 50A

BarryandSue, thanks for the hint. We're working on putting together 2-3 packages to suit a variety of electrical needs. For example...

1) An EU10i with a suitable Victron for heavy hookup-free users

2) The smaller, cheaper Victron for those who use hookup a lot

3) Something I haven't thought of yet!

We'll get our Victron, suss it out and go from there. I DO have a degree in electical engineering, and Lizzie DOESN'T! Perhaps between us we can come up with something sensible [b:1bb4886c25]Meanwhile, we'd like to hear people's electrical needs[/b:1bb4886c25]

By the way, Practical Motorhome are giving away a Victron this month!

GeorgeTelford

Reading between the lines with the victron it looks like all the power comes via the invertor, it takes the input current and charges the batteries with it and takes the power required for everything via the invertor, getting the phase in line between mains and then adding some from the invertor is not really feasable, sometimes it cvan be done with invertors but this is because the circuitry that sets the phase can be coupled and kept in phase with each other.

Sterling gear works the other way if the charger is supplying the batteries but you then switch on a hairdryer then the consumption of the charger is lowered until the hairdryer is switched off.

All Sterling gear is rated accurately ie if it says its a 1000w continous, even at 40 degrees it will run a 1000w appliance constantly 24/7

Just as an example the Victron 3000w Combi (Multi) on the surface you would expect that it is a 3000w Invertor however on checking their specification carefully you will see that it is rated at 3000 w only at 25 degrees and only 2000w at 40 degrees, check the small print here

[url]http://www.victronenergy.com/DatasheetsPDF/SinusInverterChargers/GBPhoenixMulti.pdf[/url]

If however you buy a Sterling unit it is always rated at the 40 Degree point so will always even in warm climates, still runs at its rated output 24/7

Compare a Sterling 1500w to the Victron 2500w unit and see which is better ? surprising isnt it?

Note also that Sterling are always better priced too even more so when you take the above into account.

BTW having researched this I can tell you, I use Sterling its the best equipment you can buy Pound for pound.

BTW Victron are not the only rating "cheats" all the manufacturers except Sterling Over rate their products.

Barry, Tell me what you want from a system and I will let you know what you need. all the Sterling stuff comes with clear easy instructions.

George

Anonymous

I'm interested in this bit...

"it looks like all the power comes via the invertor, it takes the input current and charges the batteries with it and takes the power required for everything via the invertor, getting the phase in line between mains and then adding some from the invertor is not really feasable, sometimes it cvan be done with invertors but this is because the circuitry that sets the phase can be coupled and kept in phase with each other."

It doesn't make a lot of sense to me, but perhaps I'm underqualified? I can't see how you can take 2200W from a 1000W generator through a 1200W (at 25 degrees C) Victron if all the power comes through the inverter?

The Victron uses technology from UPS systems to add to the incoming power (see earlier in thread). I understand that Victron is the only company with this technology at present, that's why I chose them. Furthermore, I was impressed with the peak power rating of their inverters, important for starting inductive loads (e.g. electric motors)

I take the point about continuous power rating, and it should be up to the buyer to be discerning here. 25 degrees is a reasonably typical temperature for most people. It's a balance between underselling your product, and overstating the specification. The key is disclosure, as long as the specs are clear on this matter.

I'm sure Sterling do some great stuff, and once we've had a chance to evaluate some we may start selling this brand too. After all, we'd all rather sell and buy British Wink

BillD

Hi Barry and Sue,
I am going to stick my neck out for you and try and give you a cost effective and simple solution.
Let me tell you first that I have something like 40 years experience in boats, caravans and MH. Generally the requirements are fairly similar and the solutions also are similar.
I have carried generators around (I have a Honda Eu1.0 which is a good piece of kit and supplies a good steady voltage from its inverter) and I have rarely used them for myself but have helped others out occasionally. They are like insurance, it's nice to have one and hope you don't need it.
The solution that has worked for me is to have decent battery capacity (about 2x100Ah) and a good sized solar panel. The battery takes the buffering of varying daily usage and will last several days of 'normal' usage. The solar panel will work to some extent even on dullish days and again the battery acts as the buffer.
Keep your battery topped up with water and keep an eye on the voltage if you are in doubt about the charge (the best time is first thing in the morning before the sun gets to work).
If you feel your battery is losing it go for a drive for an hour or two. In extremis go to a site and hook-up for a day.
I practice what I preach and in 2 or 3 months away at Xmas time I rarely go on a site and then it is usually because we don't feel comfotable wild camping where we are.
If you have TV or computer and require 240v get an inverter (300w cheapie does it for me).
I would not recommend an inbuilt generator unless you need aircon. or high levels of heating (winter skiing) or must have a microwave. It is an expensive and heavy piece of kit.
It doesn't do a lot of harm to leave a diesel engine ticking over for an hour or two, especially if you give it a burst of revs now and then. The problem referred to is glazing and will happen if left ticking over for many hours. We are driving basically commercial vehicle engines which in their other lives run for hundreds of thousands of miles and have you noticed bus, lorry and van drivers carefully stopping their engines!
I am not saying that all these other expensive chargers (which require the engine to run) are not good pieces of kit but I think mine is a simpler and cost effective solution which I know works.
BillD.

GeorgeTelford

Multiple invertors can be synchronised as the waveform is electronically controled so you can get 2 or more invertors in parallel (good ones Sterling Victron and some other major brands) This is what the Victron bumpf shows.

If you power everything via invertor it will cope with the extra demands, what appears to happen is that the unit measures the mains current being used, it has a manual preset so you set it to the available from shore power ampage (on a 6 amp hook up set it to 6 amps) if the unit see's that you are using 8 amps in a flash it changes to Invertor power (UPS style)

In practice the Sterling power sharing technology will do the same thing and cost you less.

Where have you got the figures 2200w from a 1000w genny Via 1200w invertor from? if those are true then He has managed to Add power too the mains input, rather than quickly replace with invertor as it appears, but I cant seem to find this amazing fact on their website. and the reference to switching between power sources seems to say that they dont actually Add power to mains rather it is replaced by the invertor.

BTW the peak from Sterling Invertors is better in most cases than the peak from an equivilent Victron (I say most because I cant be bothered with checking every one !)

DABurleigh

George,

See:
http://www.victronenergy.com/TechnicalInfo/TechPDF/Achieving%20the%20impossible.pdf

for the PowerAssist function section 1.10, and example 2.4. This is what Ben & I were discussing earlier in this thread.

Dave

GeorgeTelford

Hi DA

That example does not include the maths that were refered too, 2200 w from a 1000w genset and a 1200w invertor.

Looking at those examples non exceed the amount of power given by the 3000w invertor combi, look at all the examples not one shows a combined power in excess of the number of invertors ie with only one combi in the system the power is never over 3000w, with two the power never exceeds 6000w

Quote

"The Victron uses technology from UPS systems to add to the incoming power (see earlier in thread)"

Have looked earlier in the thread and see only assumptions based on Victron advertsing, but no-where in Victrons bumpf do I see an example that matchs or even comes close.

No ups (uninteruptable power supply) system adds to power to mains all just replace mains quickly in the event of power failure.

The main difference with the Victron system seems to be that if the shorepower is exceeded (set by you and assuming that you know what that ampage limit is) then then the Multi powers the devices instead, The advertising implies that it is adding power to the mains power.

Keeping the waveforms of 2 different invertors matched is not impossible, both have waveforms generated electronically and these controllers can be joined, trying to match the wave forms of an invertor with that of a mains supply is another story altogethor, never mind the varying voltages.

Also this could actually prove fatal say the power was out shore side and someone was working on the box, mains would then be supplied from the Victron however the most likely scenario is that the ~Victron would be attempting to supply everyone else in the loop and it would overload very quickly. It is against regs to connect a genny or invertor to your house without removing any link to the grid for this very reason.

The system I have built using Sterling gear does the following.

The charger can run on any shore supply in from 80v to 300v and the waveform can be at anything between 40hz and 400hz

under normal circumstances the Auto mains crossover will select the best power source ie shorepower first, Genny next and invertor last.

In a 4a shorepower situation I would leave the charger only running fro shorepower and power everything from the invertor, when nothing big was running the charger the 30A version would be charging the battery bank (10 X 110 ah set), if say the microwave is used then the usage would exceed the charging for a short while.

This seems to be what the Victron is doing, the only addition being the UPS switchover

George