Which Charger/Inverter manufacturer is best

[Bob Blues]

I have a digital Volt meter wired in above my desk so I can see what's happening.

 

What do you think is happening?

 

I am at float and turn off charger wait 30 mins and the voltage is 12.72.

 

Batteries still have surface charge, this is not an indication of SOC (State of Charge)

.

Turning on the laptop and DA/AD converter and it drops to 12.26v after 3 hrs of use I am at 12.05.

 

These are 'on load' readings and again not an indication of the SOC of the batteries.

 

So I turn off the system and take the dog for a last walk. On getting back to the boat the power is 12.3v

 

Depending on how long the dog walk is, this may indicate the the batteries are at very approximately 60% SOC

 

Which would imply you have used 40% of you amp.hrs, assuming your batteries are wired for 12v and batteries fully charged and in top condition, you started with 450 amp.hrs and used 180 amp.hrs or in those three hours, 60 amp.hrs per hour.

 

I doubt even a faulty inverter could use that much.

 

Something is wrong but you know that.

 

Why is the charger turned off? Is an interference problem? is it run from a generator or shorleine?

 

Laptop, is that 35 watts @ 12v dc or 240v ac

 

Again the DA/AD what voltage

 

Is the charger going into float to early?

 

Edit:

 

missed the clamp-meter bit, this will give a true idea of you actual loading, turn everything off and see what the inverter is using on its own.

 

Then turn on the other items and check again.

 

You may be surprised.

The volt meter is there to give me a rough indication on how my batteries are and when I need to charge them when I am out.

 

I have a shoreline when I am in the marina and keep the batteries on charge all the time so its only when I out cruising I run in to problems with power drain.

 

When I started on here I use to read all the posts by gibbo and yourself regarding batteries. I understand that the SOC of batteries can only be determined with a hydrometer but not having one I have to stick to the 12.7 - 12.2 voltages when left off for 30 mins which is roughly how long Luna gets a late walk. So coming back to the boat and looking at my voltages with nothing turned on I guess that is as close as a power off reading as i can get. If you think the batteries need longer to settle after load then I would be pleased to run this through a test.

 

My Clamp meter arrived today so when I get back to the boat I will run some tests.

 

All the devices run off 240v saying that, I noticed one day that the voltage from the inverter was 208v Again I will update later tonight when i get some tests done

 

 

Thanks

[Retro69]

if you just want an inverter I just bought a bestek 2kw inverter because it was a nice colour its great doesn't make any funny noises and it works £120 amazon.

[Bob Blues]

Well clamp meter applied and the unit is drawing 3 A DC at 12.3v idle at 217v AC with nothing connected.

 

When I put all the devices on and it read 10A and then dropped to 9.5A after 3 mins

 

I found the Mastervolt Freedom 20 manual and the info gives 93% efficiency with 84% at full load with an idle mode of .12A

 

The output voltage is supose to be 230V I haev seen it as low as 208v

 

Bob

[Robbo]

Well clamp meter applied and the unit is drawing 3 A DC at 12.3v idle at 217v AC with nothing connected.

 

When I put all the devices on and it read 10A and then dropped to 9.5A after 3 mins

 

I found the Mastervolt Freedom 20 manual and the info gives 93% efficiency with 84% at full load with an idle mode of .12A

 

The output voltage is supose to be 230V I haev seen it as low as 208v

 

Bob

3amps is quite a lot at idle and way more than the spec, are you 100% positive their is no load on it?

 

Where was the clamp meter reading from, make sure that it's only the inverter cable and not the DC side as well.

 

As it's a inverter/charger I presume this reading was done when off shore power!

 

Are the inverter fans going, it may be trying to cool itself down if it's in a warm place.

 

Reading the manual, the voltage will drop in idle mode, and if you have a remote you can select how sensitive going into idle is.

Edited June 5, 2014 by Robbo

[Robbo]

Just been looking at the above posts, I don't think your charging your batteries fully, you have a 100amp charger (if I read correctly and using the freedom 20?), this is around 20% of the battery banks Ah's so you are hitting them hard and will get more surface charge.

 

Use the clamp meter when charging to see how much amps the batteries are getting. If this is a high amps, charge them for at least 5-8 hours, you should see that the amount of charging amps drops to around 2-3 amps. Then disconnect the batteries so no load is on them, wait 3 hours and then check the voltage.

[Bob Blues]

3amps is quite a lot at idle and way more than the spec, are you 100% positive their is no load on it?

 

Where was the clamp meter reading from, make sure that it's only the inverter cable and not the DC side as well.

 

As it's a inverter/charger I presume this reading was done when off shore power!

 

Are the inverter fans going, it may be trying to cool itself down if it's in a warm place.

 

Reading the manual, the voltage will drop in idle mode, and if you have a remote you can select how sensitive going into idle is.

Absolutely no other load.

The clamp test was done on the large DC cable going into the unit. The Cable is about 3/4 inch thick!

The test was done completely isolated.

The inverter fans were off

 

I checked with the combi off/ not charging or inverting, the current draw was 0.12A

 

I think I will get a new one

 

Bob

Just been looking at the above posts, I don't think your charging your batteries fully, you have a 100amp charger (if I read correctly and using the freedom 20?), this is around 20% of the battery banks Ah's so you are hitting them hard and will get more surface charge.

 

Use the clamp meter when charging to see how much amps the batteries are getting. If this is a high amps, charge them for at least 5-8 hours, you should see that the amount of charging amps drops to around 2-3 amps. Then disconnect the batteries so no load is on them, wait 3 hours and then check the voltage.

 

The batteries are on charge permanently when connected to the mains and when I'm out I use the solar panel on roof + engine + 1 of two genies. (not all together!)

 

Bulk Charging only takes a few seconds before it goes to normal charge mode. I will test the charge mode and what it is charging at tonight

I do desulphate the bats every month.

 

Thanks

Bob

[Justme]

 

I think I will get a new one

 

 

 

 

 

Your call but I think you will be wasting your money.

 

All inverters use power when not under load. how much that is depends on the settings.

 

On mine (Victron Multiplus) I can have it fully on with pure sine wave,

On but at a lower voltage & usings a modified sine wave.

In power save where it monitors the elec every few seconds & only powers up if a load bigger than "X" watts comes on.

 

When its on but the elec demand is low the efficiency will be pants just the same as it is on all inverters.

[hilaryb]

Hi. Silly question from novice boater. Invertor switch to shoreline when engine not running.....and on shoreline. On or off when engine running?

[by'eck]

Hi. Silly question from novice boater. Invertor switch to shoreline when engine not running.....and on shoreline. On or off when engine running?

 

You could leave as is when engine is running but the inverter may come on automatically when shore power is removed, depending which mode your Combi is switched to. I would turn it off completely unless AC is needed whilst cruising.

[hilaryb]

Guess I need to run the fridge and small freezer whilst cruising.

[nb Innisfree]

 

 

Your call but I think you will be wasting your money.

 

All inverters use power when not under load. how much that is depends on the settings.

 

On mine (Victron Multiplus) I can have it fully on with pure sine wave,

On but at a lower voltage & usings a modified sine wave.

In power save where it monitors the elec every few seconds & only powers up if a load bigger than "X" watts comes on.

 

When its on but the elec demand is low the efficiency will be pants just the same as it is on all inverters.

Our 3kva Multiplus is quoted at 94% efficiency. Thoroughout its range from 20 watts right up to 3000 watts with PSW our BMV 501 indicates this level of efficiency remains unchanged.

[bottle]

Hi. Silly question from novice boater. Invertor switch to shoreline when engine not running.....and on shoreline. Yes On or off when engine running? Inverter ON otherwise 240v ac equipment will not work

 

 

Guess I need to run the fridge and small freezer whilst cruising. Can also be run when moored up and engine stopped, see below.

 

Hi Hilary

 

This may help you in your decision.

 

The inverter is connected to the batteries and supplies 240v ac for all your 'mains' equipment.

 

The inverter needs to be ON for that equipment to work, if not on shoreline.

 

When on shoreline the inverter is 'redundant' as the shoreline will supply all 240v ac equipment, up to the maximum it can supply, usually 16 amps about 3.3 Kw but check.

 

So for 240v ac equipment to run when away from shoreline the inverter needs to be ON

 

Your battery bank should be large enough (Amp.Hrs) to cope with the load and your charging should be able to replenish the batteries in a reasonable time.

 

Off shoreline, Engine not running, batteries supply inverter, inverter supplies 240v ac to equipment.

 

Batteries discharged, run engine to recharge batteries.

 

ps. All this if the inverter is separate unit to the charger (if you have one) and not a 'combi' (inverter, charger in one unit)

Edited June 6, 2014 by bottle

[Justme]

Our 3kva Multiplus is quoted at 94% efficiency. Thoroughout its range from 20 watts right up to 3000 watts with PSW our BMV 501 indicates this level of efficiency remains unchanged.

 

 

Thats just not possible.

 

Lets say that the inverter needs 1amp @ 12v nom just to power its internals.

 

So with a 1 amp load (at 12v nom) its efficiency is just 50% as its consuming 2 amps.

 

If you look at this graph you can see that at very low loads the efficiency is pants.

 

Ok its not the same one that you or I have but they are all very similar.

 

 

If low load efficiency is a problem get a smaller inverter.

 

If self consumption is a problem turn it off when not needed.

Edited June 6, 2014 by Justme

[hilaryb]

Thank you Bottle for taking the time to explain the Invertor and uses of...... In simple terms I could understand! It is as I had thought too which makes me regard myself less numpty than I thought!! Really appreciate it.

[nb Innisfree]

 

 

Thats just not possible.

 

Lets say that the inverter needs 1amp @ 12v nom just to power its internals.

 

So with a 1 amp load (at 12v nom) its efficiency is just 50% as its consuming 2 amps.

 

If you look at this graph you can see that at very low loads the efficiency is pants.

 

Ok its not the same one that you or I have but they are all very similar.

 

 

If low load efficiency is a problem get a smaller inverter.

 

If self consumption is a problem turn it off when not needed.

We have 14x 20 watt 240v fluorescents, just one takes 0.8+ amps and all the others when switched on in sequence take an additional 0.8+ amps each. Even with a 3kwatt load it still holds true.

 

Just to add I got into a thread exchange with a member some time ago where I stated it was 0.6 amps, I made a cock up there but can't apologise because I can't remember who it was!

 

Maybe he/she will read this post.

 

ETA: Our Multilus is 24v so efficiency is 1% better than 12v model.

Edited June 6, 2014 by nb Innisfree

[Bob Blues]

ok I def think my combi is goosed.

i put the clamp meter on and put it into charge.

It started off at 70A (Bulk)

dropped to 50 then slowly to about 13 A (charge)

then it just stopped charging activity went from 12.5A straight to 0 and indicated float.

after 20 mins it started charging again at 6 A in float mode.

 

Oh well Time to break out the credit card I think I will get a Mastervolt 12/2000/100

 

Does this machine come with a de-sulphate mode ?

 

Bob

[Robbo]

ok I def think my combi is goosed.

i put the clamp meter on and put it into charge.

It started off at 70A (Bulk)

dropped to 50 then slowly to about 13 A (charge)

then it just stopped charging activity went from 12.5A straight to 0 and indicated float.

after 20 mins it started charging again at 6 A in float mode.

 

Oh well Time to break out the credit card I think I will get a Mastervolt 12/2000/100

 

Does this machine come with a de-sulphate mode ?

 

Bob

That sounds normal. Has it been setup for your batteries with the correct voltages? Did you disconnect the batteries and checked the voltage about 3 hours later after a full charge? Edited June 7, 2014 by Robbo

[Justme]

We have 14x 20 watt 240v fluorescents, just one takes 0.8+ amps and all the others when switched on in sequence take an additional 0.8+ amps each. Even with a 3kwatt load it still holds true.

 

 

ETA: Our Multilus is 24v so efficiency is 1% better than 12v model.

 

 

How much does the inverter use with no load?

 

If your meter is reading 0.8 amps for a 1.66 amp (at 12v) load it is 200% efficient.

 

I would suspect the meter or the load values are wrong.

 

Yes the higher the system voltage the less work is needed to up it to the mains voltage.

[Robbo]

 

 

How much does the inverter use with no load?

 

If your meter is reading 0.8 amps for a 1.66 amp (at 12v) load it is 200% efficient.

 

I would suspect the meter or the load values are wrong.

 

Yes the higher the system voltage the less work is needed to up it to the mains voltage.

My guess reading the amp meter at 240v as 20watt is 0.08amp at 240v

[nb Innisfree]

 

 

How much does the inverter use with no load?

 

If your meter is reading 0.8 amps for a 1.66 amp (at 12v) load it is 200% efficient.

 

I would suspect the meter or the load values are wrong.

 

Yes the higher the system voltage the less work is needed to up it to the mains voltage.

With no load the reading varies, usually about 0.5 to 0.6amp but I've seen as little as 0.2.

 

The Multiplus is 24v so 1.66 amps will be halved.

My guess reading the amp meter at 240v as 20watt is 0.08amp at 240v

Ammeter is reading from 24v batt bank.

[Robbo]

Ammeter is reading from 24v batt bank.

That was obvious really, totally missed it tho! Must be early.

[nb Innisfree]

Just to add, the reading is probably more than 0.8amps as our BMV only reads to one decimal place, though it never reads as high as 0.9 amps with a 20 watt load.

Edited June 7, 2014 by nb Innisfree

[Jamesandlinda]

I have a Victron & am happy as Larry. As with Mastervolt you can combine the output if a generator with output from the Victron, so we are able to run a washing machine using only a Honda eu10i (very light) and the 12V/1600/60 Victron. Check out my website wwww.widebeambarge.com for a full explanation.