Charger / inverter choice confusion

[by'eck]

My new yacht has an integrated ( single screen unit) for the :

 

Radar

GPS

Sounder

Chart Plotter

NavTex

 

I'm not happy but that's the way things are going these days.

One screen damaged, one bit of wiring damaged and the lot has gone.

 

I will be putting a repeater station at the helm so that should help a bit.

I will be getting a back up GPS and some 'proper' paper charts and will be using my 'tablet' based nav system that covers European waters as a back up.

 

It may seem a worry but you seem to have already found a way to provide screen redundancy.

 

The installation I had on last boat which I posted the schematic of, also relied on an MFD screen although I did have stand-alone Navtex. The Raymarine MFD was very reliable.

 

A bit of redundancy I didn't even plan was that the AIS transponders regulatory built-in GPS fed the same NMEA bus as the dedicated mushroom GPS rx on handrail. When I sold the boat it was sailed back across the Atlantic by a "professional" crew. A meeting with the new owner when back in the UK revealed the mushroom GPS had failed at some point on the passage, but the one in the AIS unit had taken over seamlessly to the extent no one noticed.

[Top cat]

Hmmm thats a point, my Victron solar controller floats my sealed leisure batteries at 13.8V I can't see any way of adjusting it. But I notice that charge current is usually quit low often less than a amp. I presume that at such low currents little damage would be done, is that correct?

 

Top Cat

[nicknorman]

Hmmm thats a point, my Victron solar controller floats my sealed leisure batteries at 13.8V I can't see any way of adjusting it. But I notice that charge current is usually quit low often less than a amp. I presume that at such low currents little damage would be done, is that correct?

Top Cat

There's a thing called "positive plate erosion". Don't ask me what it is but I believe that too high a float voltage (over a long period) can cause it. However since we are talking solar, it's not going to spend a lot of time in float so it's probably not a problem.

[Alan de Enfield]

 

It may seem a worry but you seem to have already found a way to provide screen redundancy.

 

The installation I had on last boat which I posted the schematic of, also relied on an MFD screen although I did have stand-alone Navtex. The Raymarine MFD was very reliable.

 

 

 

Our last 'discussions' were around installation of Radar on my Motor Cruiser - got that sorted, but Now I have bought a 38 foot blue water Cat. The MFD is a "Furuno Navnet" system. It works fine, but I like to have multiple redundancy.

I have two spare Garmin GPS Sounders and a spare hand held GPS and 4 VHF radios ( 2 fixed and 2 Hand Helds) on the cruiser, looks like I'll have to move them around a bit.

 

Electronics are getting more reliable but accidents can still happen.

[blackrose]

I prefer the Combi approach. It all hangs together and just works, seamlessly.

I've heard this before from a bloke on the most amazing new build traditional boat I've ever seen at Saul junction with a big old vintage engine. Kelvin I think, but can't remember. Anyway, he was telling me about his "seamless" electrics but it all seemed a bit paradoxical and I couldn't really understand the advantages. So with a separate inverter and charger my electrics go off for a few seconds between the two while for those with combis it stays on. Is that really it? It just seems like such a lot of money for such a minor benefit.

 

As far as the OPs question goes... the question to ask is why do you need a pure sine wave inverter? To run a microwave? I hope you have a good battery bank. If I were in your position I think I'd just spend a couple of hundred quid on a decent charger and leave it at that.

Edited November 10, 2015 by blackrose

[Top cat]

There's a thing called "positive plate erosion". Don't ask me what it is but I believe that too high a float voltage (over a long period) can cause it. However since we are talking solar, it's not going to spend a lot of time in float so it's probably not a problem.

I suppose it depends on how long is too long, obviously they drop off float at night even when the boat is unoccupied but averaged over the year that could be maybe 1/6th of the time. I hadn't thought about positive plate erosion and it sounds like it is voltage rather than current driven.

 

Top Cat

[matty40s]

I've heard this before from a bloke on the most amazing new build traditional boat I've ever seen at Saul junction with a big old vintage engine. Kelvin I think, but can't remember. Anyway, he was telling me about his "seamless" electrics but it all seemed a bit paradoxical and I couldn't really understand the advantages. So with a separate inverter and charger my electrics go off for a few seconds between the two while for those with combis it stays on. Is that really it? It just seems like such a lot of money for such a minor benefit.

 

 

That would be RW Davis ...Enid.

 

The bloke who couldn't get a TV signal to watch the Grand Prix in Paddington Basin and went to Maplins and spent £135 trying to sort it out.

 

He bought me a beer when I showed him the Tune to new transmitter function on his posh TV.

[nicknorman]

I've heard this before from a bloke on the most amazing new build traditional boat I've ever seen with a big old vintage engine. Kelvin I think, but can't remember. Anyway, he was telling me about his "seamless" electrics but it all seemed a bit paradoxical and I couldn't really understand the advantages. So with a separate inverter and charger my electrics go off for a few seconds between the two while for those with combis it stays on. Is that really it? It just seems like such a minor benefit.

You're talking it down a bit. It just means that if I plug in the shore power, the boat uses shore power for the sockets and battery charging. If I turn on the Travelpower the boat uses that for the sockets and the battery charging. If neither are on the sockets are fed from the inverter and the batteries start to discharge into the Dc system. All without operating any switchery. Perhaps you don't see that as a big advantage but to me it is just elegant.

 

But also there are a few extras - if the shore power is limited, as it is at some marinas, you can set it to boost the incoming shore power. So perhaps a bollard limit of 6A, and once the demand exceeds that the charger shuts off and the inverter kicks in with frequency and phase matched additional power.

 

If you are on shore power and it suddenly trips or is unplugged, the inverter (which has been tracking the incoming frequency and phase) picks up the load instantly without any phase or frequency jump. This can be significant for some delicate electronics such as appliances controlled by electronic timers.

 

I suppose you can liken it to anything vaguely automatic like self cancelling indicators in cars, pop up toasters and kettles that switch themselves off. Under cold scrutiny the automation seems of little use, but once you have it you wouldn't want to go back.

[blackrose]

 

That would be RW Davis ...Enid.

 

The bloke who couldn't get a TV signal to watch the Grand Prix in Paddington Basin and went to Maplins and spent £135 trying to sort it out.

 

He bought me a beer when I showed him the Tune to new transmitter function on his posh TV.

Possibly. I just went to look at the dry dock and he's moored right next to it? I just got chatting to him. Amazing boat.

You're talking it down a bit. It just means that if I plug in the shore power, the boat uses shore power for the sockets and battery charging. If I turn on the Travelpower the boat uses that for the sockets and the battery charging. If neither are on the sockets are fed from the inverter and the batteries start to discharge into the Dc system. All without operating any switchery. Perhaps you don't see that as a big advantage but to me it is just elegant.

 

But also there are a few extras - if the shore power is limited, as it is at some marinas, you can set it to boost the incoming shore power. So perhaps a bollard limit of 6A, and once the demand exceeds that the charger shuts off and the inverter kicks in with frequency and phase matched additional power.

 

If you are on shore power and it suddenly trips or is unplugged, the inverter (which has been tracking the incoming frequency and phase) picks up the load instantly without any phase or frequency jump. This can be significant for some delicate electronics such as appliances controlled by electronic timers.

 

I suppose you can liken it to anything vaguely automatic like self cancelling indicators in cars, pop up toasters and kettles that switch themselves off. Under cold scrutiny the automation seems of little use, but once you have it you wouldn't want to go back.

I guess if that stuff is important to you then that's fine. Each to their own and all that. It's not important to me. I just prefer simpler manual systems. Plus I'm a tight wad!

[Phil Ambrose]

Possibly. I just went to look at the dry dock and he's moored right next to it? I just got chatting to him. Amazing boat.

 

I guess if that stuff is important to you then that's fine. Each to their own and all that. It's not important to me. I just prefer simpler manual systems. Plus I'm a tight wad!

I like simple too and though my inverter cam be wired for UPS I choose not to because the frequency that we lose power in our marina means that many people have been caught out with an empty domestic bank dude to the inverter kicking in unnoticed while the washing machine is on, electric oven (yes) and they are hoovering. I like to choose simple as that.

Phil

Edited November 10, 2015 by Phil Ambrose

[by'eck]

Ironic that the keep it simple camp seem to favour the separates when a Combi is simpler to install and simpler to use, as in less chance of user error. I refer back to post #8

 

There are a lot of pitfalls to wiring up the double pole AC selector switch otherwise, although if done properly with the right components shouldn't be an issue.

[bottle]

DavidExpert.

 

Victron Combi's also have the charger output set to 75% of maximum (what it says on the label), this can be changed but usually means the use of a laptop, program and interface.

[Phil Ambrose]

Ironic that the keep it simple camp seem to favour the separates when a Combi is simpler to install and simpler to use, as in less chance of user error. I refer back to post #8

 

There are a lot of pitfalls to wiring up the double pole AC selector switch otherwise, although if done properly with the right components shouldn't be an issue.

So once set up correctly it's simple.

Phil

[PeterG]

So how long would fitting a new Victron Combi in place of another failed unit be expected to take then as apposed to fitting a seperate charger and inverter?

[by'eck]

So how long would fitting a new Victron Combi in place of another failed unit be expected to take then as apposed to fitting a seperate charger and inverter?

 

Well only one set of heavy current battery cables with a Combi for a start, plus two sets of mains cable connections, in and out which will be present from previous Combi installation.

 

With seperates its difficult to say as dependant on connections needed - does the charger supply lead terminate in mains plug or requires hard wiring etc. There will be need of two sets of battery connections though plus mains connection from inverter.

[PeterG]

So possibly a couple of hours work for a combi and say a day for seperates should do it?

[Keith M]

 

Not sure I would agree with the cost issue unless you are putting a high value on installation. I fitted separate 1800 watt quasi sine Sterling inverter and one of their three output 50 amp chargers on my last boat during a re-fit, to replace the duff Victron Combi. Even with the double pole three way AC selector I bought and fitted, the total cost was significantly less than the equivalent Sterling Combi available at the time. Wiring the switch was not for the faint hearted though and I totally agree many builders/installers would find fitting one challenging to do correctly.

 

FWIW back with a Combi now but with second backup charger for redundancy. More difficult to make an operational mistake with them as well once set up.

 

By just looking at RRP's of mastervolt equipment

 

12/100 battery charger £ 971.00

12 / 2000 inverter £ 1152.00

Total £ 2123.00

 

12 / 2200 / 100 inverter /charger £ 1476.00

 

There is nearly £ 650.00 different

 

If feel this is significant amount

 

Keith

[nicknorman]

By just looking at RRP's of mastervolt equipment

 

12/100 battery charger £ 971.00

12 / 2000 inverter £ 1152.00

Total £ 2123.00

 

12 / 2200 / 100 inverter /charger £ 1476.00

 

There is nearly £ 650.00 different

 

If feel this is significant amount

 

Keith

It is, but I think it would be wrong to presume that this was the prime driver for fitting Combis. It is just another minor advantage which, in the context of a new boat, is pretty trivial. If we ever have another boat built I'll specify a Combi, but it won't be for cost reasons.

[PeterG]

So cheaper to buy and install, simpler as well, but if you get a failure could be a larger impact and more expensive to replace?

[by'eck]

 

By just looking at RRP's of mastervolt equipment

 

12/100 battery charger £ 971.00

12 / 2000 inverter £ 1152.00

Total £ 2123.00

 

12 / 2200 / 100 inverter /charger £ 1476.00

 

There is nearly £ 650.00 different

 

If feel this is significant amount

 

Keith

 

Can't argue with that but equally the costings I quoted were a deciding factor for me at the time when funds were low. I note Sterling have reduced their prices on Combi's recently. Another issue was weight - living in the Caribbean I typically bought boat equipment in the UK and took it back to my boat as luggage. VAT was then re-claimed via the personal export scheme. The seperates weight was significantly less than the Combi.

[Sea Dog]

To be fair, you're not really a typical Narrowboat inverter charger purchaser then by 'eck. Most buyers here, not least the OP, won't be flying their kit across the pond and claiming their vat back.

[by'eck]

To be fair, you're not really a typical Narrowboat inverter charger purchaser then by 'eck. Most buyers here, not least the OP, won't be flying their kit across the pond and claiming their vat back.

 

I am now

 

I mentioned the background more to illustrate why I chose seperates on that occasion. I wouldn't again.

[Sea Dog]

I am now

 

I mentioned the background more to illustrate why I chose seperates on that occasion. I wouldn't again.

Ah, I thought you were advocating separates for reasons which may not have influence in the OPs case. That's cleared that up anyway. Quite understand why you'd have done that then, and it's interesting to hear that you wouldn't now.

 

Also interesting to read other folk's views and ideas here. I'm left thinking that separates probably make sense at the lower end of the market where failure is more of an issue, but a Combi comes out better as long as you buy a reliable brand - probably Victron or Mastervolt. Not without their issues, of course, and OK if you can afford them, but there's far fewer threads here starting with "Help - my Victron/Mastervolt.... " than with Chinese/eBay/Sterling, even allowing for market size.

[by'eck]

Ah, I thought you were advocating separates for reasons which may not have influence in the OPs case. That's cleared that up anyway. Quite understand why you'd have done that then, and it's interesting to hear that you wouldn't now.

 

Also interesting to read other folk's views and ideas here. I'm left thinking that separates probably make sense at the lower end of the market where failure is more of an issue, but a Combi comes out better as long as you buy a reliable brand - probably Victron or Mastervolt. Not without their issues, of course, and OK if you can afford them, but there's far fewer threads here starting with "Help - my Victron/Mastervolt.... " than with Chinese/eBay/Sterling, even allowing for market size.

 

I'm intrigued why reliability is considered greater with separates. All electronic devices consist of a number of components each of which could fail. In a Combi I wonder how many are common to both charger and inverter. Transfer relay sure, but are they any less reliable than a manual transfer switch and a substantial amount of external wiring? I suppose many would regard failure of any part of a Combi reason for replacement but if say the inverter fails no reason the charger wouldn't work and vice versa.

 

You may have answered the issue pointing out that cheaper Chinese imports cover a range of budget priced separates, although very few (if any) Combi's.

[Sea Dog]

I don't subscribe to a Combi being inherently less reliable than separates either, certainly not in terms of quality units. I can see why some may be attracted by the idea that, if something does go wrong, it could be cheaper and easier to replace only that particular unit with separates. However, I'm in the fortunate position of having a Mastervolt 100/2500 Combi and would replace it with another similar unit in a heartbeat if it died. I fervently hope it doesn't though! (££££s)