Electrical techies answer please. (1 Viewer)

haganap

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I'm an oldbie MH number 9
Ok a sort of shared post between andyman and me.

My generator is a Honda eu10. When plugged in to my MH it produces approx 8-10 amps for charging.

When I'm on electric hook up the electric supplied from my house supplies approx 16 amps

So, if my generator produces 240 power, why when I use it on a rally does it only charge at 8-10 amps but real electric does the job at 16 amps (or in andymans case 18amps )


T I A
 

pappajohn

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I reckon you are a bit optomistic on your power production Paul

your Honda produces 1000watts (around 900watts actually).....1000watt divided by 230volts is just 4.34amps

a 2000watt Honda will produce what you say....8.68amps.

your charger may be producing 8amps at 12v


its all down to the gennies maximum output....in your case 1000watts

mains electric is far, far higher than the 13amps you mention.
household mains are generally protected by an 80amp fuse at the meter so the combined power used could be 80amps before the fuse blows.

upgrade the house wiring and put in a 150amp fuse and you get 150amps.
 
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Terry

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well that educates me for one ::bigsmile:In my (simple) thoughts I wrongly thought if you plugged the genny into the van leccy using the H/U point it would give say 20 amps from the onboard 20 amp charger :Smile: obviously (now) it don't - ::bigsmile: time for a green machine Haggers :winky: or run the engine :thumb: ::bigsmile:
terry

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hilldweller

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Ok a sort of shared post between andyman and me.

My generator is a Honda eu10. When plugged in to my MH it produces approx 8-10 amps for charging.

When I'm on electric hook up the electric supplied from my house supplies approx 16 amps

So, if my generator produces 240 power, why when I use it on a rally does it only charge at 8-10 amps but real electric does the job at 16 amps (or in andymans case 18amps )


T I A

16A at 12V is only 192W

10A is 120W obviously.

I wonder if your generator is faulty. You are quite right in expecting the same performance from mains and genny.
 

pappajohn

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16A at 12V is only 192W

10A is 120W obviously.

I wonder if your generator is faulty. You are quite right in expecting the same performance from mains and genny.
True Brian, but Pauls talking 10amps @ 230v unless i misunderstand his post and he means the 12v outlet on the genny..
16amp x 230v = 3680watt...Pauls genny is rated at just 1000watts max hence 4.34amps

the 12v outlet is usually rated at around 8amps...mine is a 2.2kw @230v but just 8amps @12v
 
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haganap

haganap

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I reckon you are a bit optomistic on your power production Paul

your Honda produces 1000watts (around 900watts actually).....1000watt divided by 230volts is just 4.34amps

a 2000watt Honda will produce what you say....8.68amps.

your charger may be producing 8amps at 12v


its all down to the gennies maximum output....in your case 1000watts

mains electric is far, far higher than the 13amps you mention.
household mains are generally protected by an 80amp fuse at the meter so the combined power used could be 80amps before the fuse blows.

upgrade the house wiring and put in a 150amp fuse and you get 150amps.

16A at 12V is only 192W

10A is 120W obviously.

I wonder if your generator is faulty. You are quite right in expecting the same performance from mains and genny.




Ok you both can't be right , I believe in Papajohn but Andyman believes in Brians explanation. What I can say is there is nothing wrong with my Genny

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haganap

haganap

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I'm an oldbie MH number 9
But my charger is 18amp therefore when my Genny runs why is it not producing 18amps like andyman believes , m Genny makes 240v electric right ?
 

Techno

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The maximum output of your 1K genny is 1K which divided by 230 volts is as said not much more than 4 amps

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pappajohn

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But my charger is 18amp therefore when my Genny runs why is it not producing 18amps like andyman believes , m Genny makes 240v electric right ?
Right Paul.....turn on all yer lights, the pump and anything else 12v powered until your battery is totally dead.

the plug in the genny......it will charge the batteries at 18amps...for a while.

your charger will only bang in as much power as the batteries need...the better the charge state the less amps needed to top up.
as the battery voltage rises, the charging amps drop.

mine is a 45amp charger but never produces much more than a few amps, as the 170w solar panel keeps the batteries pretty much topped up most of the time.....the charger then has nowt to do but twiddle its thumbs.
 
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haganap

haganap

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The maximum output of your 1K genny is 1K which divided by 230 volts is as said not much more than 4 amps

Right Paul.....turn on all yer lights, the pump and anything else 12v powered until your battery is totally dead.

the plug in the genny......it will charge the batteries at 18amps...for a while.

your charger will only bang in as much power as the batteries need...the better the charge state the less amps needed to top up.
as the battery voltage rises, the charging amps drop.

mine is a 45amp charger but never produces much more than a few amps, as the 170w solar panel keeps the batteries pretty much topped up most of the time.....the charger then has nowt to do but twiddle its thumbs.


Again you can't both be right, or i misunderstand . John I have done as you say, I promise you that my Genny produces less amps than my house electric, is it the output of the Genny as was my suggestion to Andy or something else?
 
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haganap

haganap

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well that educates me for one ::bigsmile:In my (simple) thoughts I wrongly thought if you plugged the genny into the van leccy using the H/U point it would give say 20 amps from the onboard 20 amp charger :Smile: obviously (now) it don't - ::bigsmile: time for a green machine Haggers :winky: or run the engine :thumb: ::bigsmile:
terry

What your saying is what Andy was saying but I know it don't work like that, no need for a green machine with my 50 amp charger :winky:

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JeanLuc

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Assumption - we're talking about a 1 KVa gennie plugged into the EHU point of the motorhome, and delivering 230V AC.
What is the maximum input demanded by the onboard charger? In the case of my Electrobloc it's 1.7 amps to produce a maximum charging current of 18 amps DC. 1.7 amps divided into 230V = 135W which the EU10i is more than capable of delivering, in fact the rated maximum output current is stated as 3.9 amps.
Assuming the charger on your Bessie is of a similar spec., there should be no problem.

The only answer to the conundrum that occurs to me is to ask what is the state of discharge of the leisure batteries? You will only see 18 amps charging current if they are quite well discharged, otherwise, the system will reduce the charging current accordingly. It's the same with the solar panel. If the batteries are low, than in full sun I can see 5-7 amps going in on a bright day. If I wake up long after the sun, the input can be down to 1-2 amps as the batteries are nearly full by then.
 

Terry

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What your saying is what Andy was saying but I know it don't work like that, no need for a green machine with my 50 amp charger :winky:

Hi Paul I only have a 22 amp charger and 1 110 amp hr battery -no solar,no genny and never ran out of power ::bigsmile:I have also never checked what the batt charger is giving out :thumb:Simply plug in and forget :thumb:I will look/worry at things when something goes wrong :Smile:
BTW liking this post as said in my simple mind /like Andy but I can also see the 4/5 amp point that could make sense-- I will have to ask my mate Paul to explain it to me :ROFLMAO:I can hear is answer now WHY do I want to know or mess, everything is working so don't touch it :Doh::Sad:
terry
 

Techno

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I can only think that your generator isn't sensing enough demand to run at its maximum output? It should be reving it's nuts off :roflmto:

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pappajohn

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Again you can't both be right, or i misunderstand . John I have done as you say, I promise you that my Genny produces less amps than my house electric, is it the output of the Genny as was my suggestion to Andy or something else?
Of course it does Paul...the max output of your genny is just 1 kilowatt...which at 230v is 4.34amps.
you cant have more amps than the machine can produce.

your charger on the other hand can.....the lower the output volts the higher the amps (for the same watts.)

my onboard genny is a 5500watts @ 120volts....thats 45amps.
it also produces 230v via the transformer...5500watts @230volts....thats just 24amps from the same machine.

same watts/higher volts/lower amps.
 
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bungle.bear

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Well, I think there is a lot confusion over this post,

Some poeple are talking about 18amps of battery charger current and some poeple are talking about 4.3 amps of generator current. but they are not the same because 1 is 12V DC and 1 is 230V AC.

The only way to compare them is to convert both to power measured in watts.

So we will start with the battery charger,
If it is a 18amp charger (maximum) this is multiplyed by the voltage and equals power in watts.

So 18amp X 12volts = 216watts.

The 18amps charging will drop as the battery becomes charged. I suspect when you run your generator the battery may have been coming up to fully charged.

The generator is rated at 1000W or 1kW peak power, so if you divide watts by voltage then you will equal current.

So 1000w / 230V = 4.34amps.

So you can see using power that if your battery charger was working flat out (18A @12V =216W) this would only be around 1/5th of the total power your generator can produce.

This means that there should be no difference in charging between your generator than a electric hook up. the only reason you would see different charge current (amp) is that the battery is at different states of charge.

Regards Anthony

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pappajohn

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Well, I think there is a lot confusion over this post,

Some poeple are talking about 18amps of battery charger current and some poeple are talking about 4.8 amps of generator current. but they are not the same because 1 is 12V DC and 1 is 230V AC.

The only way to compare them is to convert both to power measured in watts.

So we will start with the battery charger,
If it is a 18amp charger (maximum) this is multiplyed by the voltage and equals power in watts.

So 18amp X 12volts = 216watts.

The 18amps charging will drop as the battery becomes charged. I suspect when you run your generator the battery may have been coming up to fully charged.

The generator is rated at 1000W or 1kW peak power, so if you divide watts by voltage then you will equal current.

So 1000w / 230V = 4.34amps.

So you can see using power that if your battery charger was working flat out (18A @12V =216W) this would only be around 1/5th of the total power your generator can produce.

This means that there should be no difference in charging between your generator than a electric hook up. the only reason you would see different charge current (amp) is that the battery is at different states of charge.

Regards Anthony
Thank you.....my point exactly, as previously posted. :thumb:
 

jonandshell

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Hi Paul, just sell the Honda as Nikki asks! Your Sterling will take up the slack!

The girl needs clothes and shoes!::bigsmile:
 
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haganap

haganap

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Ok, All thing's being equal and bearing in mind that someone actually told me the B2B system would not work, we are all in a very fortunate position today..:Smile:

For, today, I am off work and off to the dentist in a moment, but on my return, and in the interest of boredom relief,I will photograph and even video (because Im sad) what exactly happens.

In otherwords in the name of fun, I shall be conducting an experiment for you all, to test the theory of Bungle Bear and others.

The test shall be conducted as follows.

1) The batteries will be discharged to the same state of 75% meaning a 1/4 of the charge has been removed. This will be done by utilising my inverter and hair dryer and monitored on my extremely acurate and expensive NASA battery Monitor (BM1)

2) I will then fire up the Genny, then plug it in, and again my BM1 will monitor exactly how many amps the batteries are receiving. May I add my Genny is in perfect condition, its honda and has been recently serviced and tested FULLY, so any descrepencies in the accuracy of the product are dismissed.

3) following 15 mins of charging and AMP monitoring I will then dishcarge the batteries whilst drying my hair again to establish the same level of discharge of the batteries.

4) I will then plug in my electric hook up, and again, consult the BM1 to establish the charge going in to my batteries. All Lights and interior stuff will be off for both stages of this experiment.


5) having then discharged the batteries again, I will then utilise my B2B charger to show its efficiency in charging the battery bank back to full, this will serve no other purpose and should be removed from the experiment. I am only doing this because I can and that because I love it and its a new toy.


So, what I expect to happen and can't explain, despite your kind attempts to explain such to a thicko,,,,

If, I plug in my Genny, it makes 240v, and therefore should be no different to the house electric. It does not "rev its nuts off" as suggested, it merely ticks over unless demand in the van, hairdryers etc are being used.

Experience tells me the above is not the case and that it is quicker to charge using the house electric than the Genny. But, I could be wrong, but the experiment will also prove, that the quickest of all will be too charge using my b2b charger as per my initial conversations with Andy.

I have a solar panel too which will be removed in the interest of this experiment. :thumb: well disconected.

Motorhoming and the pursuit for power? Don't you just love it :thumb:
#

before anyone else tells me that I don;t need one and you get through all year with nothing more than a upside down funster badge connected to the batteries with a bit of nylon fishing wire, my power demands in the winter are very high. High level of heating from the blown air which will be on 24/7, TV, Hair dryer, Hair Curlers, Computers you name it, if its electrical it's used in our van. :RollEyes:

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Terry

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I won't hold my breath Paul but you have my attention :thumb::winky:
terry
 

sedge

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There is a Fatal Flaw in your plan.

Drying your hair couldn't possibly discharge even a gnat's whisker's worth of your battery power.

Failed ........
 

hilldweller

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Drying your hair couldn't possibly discharge even a gnat's whisker's worth of your battery power.

WOW. Talk about low blow.

It started about 6 feet underground and accelerated violently upwards until it met with poor old hagger's testicles.

Kerrrrrrrrrrrrrrrrrrunchhhhhhhhhhhhhh.

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haganap

haganap

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Ok, the results are in, so here we go.......

I did forget to mention previously the health and safety blurb,

Please remember I is a professional idiot,
with no training whatsoever
therefore would all non idiots
please refrain from trying this at home.


Half my mouth is actually frozen as I carried out this experiment thanks to the dentist, once again adding more to the danger.....

I have also just found out I can only add 5 pictures at a time so here you can see in this pointless experiment.

Picture 1 from left to right.
The BM1 as I entered my van, everything fully charged.
Picture 2. Im not sure what that is, its a long time since I saw anything like it.
Picture 3 is a honda genny, listen carefully? can you here it running? of course not.
picture 4 is my solar thingymagigy regulator
picture 5 is the discharge running my the gun shaped object in picture 2 through my 1800w inverter showing a massive 96 amps of power being thrown away in the interest of science.


more to follow.
 

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haganap

haganap

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I'm an oldbie MH number 9
So moving on.

With the batteries reduced to 80% the Gun shaped object was terminated.

I then started and ran the genny, giving it a few minutes to warm up, I then plugged it in to the electric socket and what you see in ->

Picture 2 is the amount of amps now flowing in to the batteries to restock them and get them charged again

After some 5 mins and in a little deviation from the experiment to rule out Jean-Lucs theory of battery stabilisation I removed the Genny and then plugged in the Electric charger , as you can see in
Picture 3 it gave me an outstanding 19.8 amps of charge flowing in to those lead acid beauties.
This is or was 3.8 amps more than what the Genny was giving me, proving that my theory was correct. However, very much more than what I thought I was getting from my Genny when I initally was speaking to Andy.

In Picture 4, I have simply pulled out the electric and started the engine to use the B2B charger, more than doubling what the electric was giving me and again proving that this is surely the most effective way of getting the power required.



so the result would be-

excluding picture 4 (that was me showing off) :Blush:

Genny is beaten by my house... so again I must ask why? what happened?


If nothing else I have enjoyed learning about the electrical side of battery charging over the past few months.
 

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Terry

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Thanks Paul :thumb: no idea why this got my interest :Doh: but it did / has ::bigsmile:When showing off did you run the engine as well :winky:--again out of interest how much juice do you get with just engine running ie on tick over and say 2 thou revs -it does not matter if you don't want to do it -just my curiosity and I don't have a posh battery state monitor :ROFLMAO: but when you do another run let me know and I will sponsor you for a tenner :thumb:
terry

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haganap

haganap

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Thanks Paul :thumb: no idea why this got my interest :Doh: but it did / has ::bigsmile:When showing off did you run the engine as well :winky:--again out of interest how much juice do you get with just engine running ie on tick over and say 2 thou revs -it does not matter if you don't want to do it -just my curiosity and I don't have a posh battery state monitor :ROFLMAO: but when you do another run let me know and I will sponsor you for a tenner :thumb:
terry

Engine was on tick over terry , makes little difference if I rev it :thumb:

I'm still confused thiugh
 

Terry

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Engine was on tick over terry , makes little difference if I rev it :thumb:

I'm still confused thiugh

::bigsmile: so am I :thumb: but it does not take a lot :winky:
Don't forget to let me know next time you do a run :thumb:
terry
Paul what do you get from just the alternator working ?-I assume it kicks out more or less the same once it starts charging whether just above tick-over or 3 thou revs - thinking along a green machine type toy-I already have a small Honda engine and tank-just need to pick it up and find a alternator in the garage-(two in there somewhere) then it's down to my mate who welds ::bigsmile:
 

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