How many watts will a 30A battery charger use?

[Mitchellmoxo]

A 30A charger would be suited to a battery bank of 300Ah max, according to the generally-accepted blurb.

 

How big is yours? (Battery bank)

My battery bank is 330ah. What charger would you reccomend if my battery bank was any bigger?

 

Mitch

[by'eck]

My battery bank is 330ah. What charger would you reccomend if my battery bank was any bigger?

 

Mitch

 

Well lets say you added another leisure battery giving 440 Ah, and you wanted quick re-charge times. Anything up to 100 amps would be fine.

[bottle]

My battery bank is 330ah. What charger would you reccomend if my battery bank was any bigger?

 

Mitch

 

Here you go have a read.http://www.smartgauge.co.uk/chargesize.html

[James T Berk]

15V x 30A =450W (transformer close enough to 100% efficient not to worry about)

Rectifier losses 2x0.8V = 1.6V x 30A = 48W

Total 500W

Pf 0.8

500W / 4 = 125 x 5 = 625W worst case.

[valrene9600]

Well lets say you added another leisure battery giving 440 Ah, and you wanted quick re-charge times. Anything up to 100 amps would be fine.

Would you say using a petrol genny and 100amp sterling combi charger would be cheaper and quicker than using a 90 amp alternator on the engine.

 

Edit. 440ah bank

Edited November 19, 2015 by valrene9600

[by'eck]

Would you say using a petrol genny and 100amp sterling combi charger would be cheaper and quicker than using a 90 amp alternator on the engine.

 

Edit. 440ah bank

 

Since they are similar current ratings it would depend on the regulated (absorb in case of charger) voltage each was set to. I would favour the genny though providing it has enough power to run the Combi's charger which will save running the engine.

 

Sounds like you have the same Combi as me so would add that my Kipor IG2600 genny running on propane only just manages to power it.

[valrene9600]

Since they are similar current ratings it would depend on the regulated (absorb in case of charger) voltage each was set to. I would favour the genny though providing it has enough power to run the Combi's charger which will save running the engine.

 

Sounds like you have the same Combi as me so would add that my Kipor IG2600 genny running on propane only just manages to power it.

1400 frame genny is OK on 50 amp charge setting so sounds like it might not be a good idea to set it at 100 amp.

[by'eck]

1400 frame genny is OK on 50 amp charge setting so sounds like it might not be a good idea to set it at 100 amp.

 

If that's a 1400 watt genny you are referring to its going to be seriously struggling with 100 amp charger, initially at least.

 

Intrigued you have a 50 amp charger setting on your Sterling Combi - mine certainly hasn't. It has put out 106 amps initially into batteries though, so you can imagine the start up load on a generator.

[onionbargee]

27 amps out of my electroquest, which I run off a kipor kge2000, it gets a decent load on it but still purrs away quietly, its the perfect set up as far as I'm concerned.

[Loafer]

My battery bank is 330ah. What charger would you reccomend if my battery bank was any bigger?

 

Mitch

 

I believe ANY charger will 'work', but the accepted rule-of-thumb is 10% of Ah capacity of your bank. It'll just take longer if it's a smaller percentage.

 

However, a 10A charger into a 1000Ah battery bank might not get them up to charge from a very low SOC.

 

I've seen a 25A charger ok with 450 Ah, but with solar support so the 25A isn't required for very long. If your charger is happy to run at full output for an hour or so before the current reduces below 25A, then I'd say it was OK.

 

2p.

[valrene9600]

If that's a 1400 watt genny you are referring to its going to be seriously struggling with 100 amp charger, initially at least.

 

Intrigued you have a 50 amp charger setting on your Sterling Combi - mine certainly hasn't. It has put out 106 amps initially into batteries though, so you can imagine the start up load on a generator.

It,s 10 years old and can be set to 25,50,75 and 100.

DAI 3000c 12xx. Is the model

[valrene9600]

I would like to get a Genny that would run the immersion(1kw) and maybe the 50 amp charger. Trouble is not being able to run the immersion on it's own as it's wired into the 230v fuse board.

The inverter charger has a minimum 25 amp charge setting so my question is what size Genny would power the immersion and the 25 amp charger.

[Paul C]

I would like to get a Genny that would run the immersion(1kw) and maybe the 50 amp charger. Trouble is not being able to run the immersion on it's own as it's wired into the 230v fuse board.

The inverter charger has a minimum 25 amp charge setting so my question is what size Genny would power the immersion and the 25 amp charger.

 

....can be solved by a minor amount of re-wiring.

[valrene9600]

....can be solved by a minor amount of re-wiring.

It would be handy to just heat water in summer when normal power is from solar.

How would it need to be wired.

[Paul C]

It would be handy to just heat water in summer when normal power is from solar.

How would it need to be wired.

 

Basically you "split" the incoming shorepower/hook up socket to two parts, one part is "shore power only" and one part would go to the inverter/charger or a selector switch (combis have, effectively, a selector switch built in). If you split it, both bits need a RCB and MCBs as appropriate. And don't forget earthing and galvanic isolation too.

[valrene9600]

Basically you "split" the incoming shorepower/hook up socket to two parts, one part is "shore power only" and one part would go to the inverter/charger or a selector switch (combis have, effectively, a selector switch built in). If you split it, both bits need a RCB and MCBs as appropriate. And don't forget earthing and galvanic isolation too.

OK I will investigate further. Thanks.

My inverter has a bypass but being unable to zero the battery charger part it is too much

For my 1400 Genny.

Splitting as you say and the extra rcb etc and labour cost, not sure I would be confident, might mean it would be cheaper to upgrade the Genny.

[by'eck]

I would like to get a Genny that would run the immersion(1kw) and maybe the 50 amp charger. Trouble is not being able to run the immersion on it's own as it's wired into the 230v fuse board.

The inverter charger has a minimum 25 amp charge setting so my question is what size Genny would power the immersion and the 25 amp charger.

 

Well I'm biased since I have Kipor IG2600 (2300 watts continous) with LPG conversion which performs faultlessly despite being run near max output for a lot of the time. This will certainly be more than adequate for your requirements.

 

TBH given the relatively low prices of these gennies I'm surprised so many buy smaller ones, which at best are marginal for their requirements, just to save a few quid. It could be that they are locked into the must be a Honda camp and would rather buy an inadequate size one because the overpricing doesn't allow purchase of anything larger from that manufacturer. Seems counter productive to me though.

 

The immersion and a plain charger if you have one, should be wired separately from the main AC distribution system if this is fed via a Combi. This because you don't want inverter support for either of these appliances.

[Theo]

A word of caution.

 

I bought a Kipor ig1000 which has a npminal power output of 1000W. I bought it to power a 20A Sterling charger which was fine, except that it was taking far too long to charge the batteries.

 

I then bought a 50A Sterliong charger which has a advertised power consumption of 750W. As soon as the charger came on line it overloaded and tripped the gennie.I complained to Sterlng who basically said "Tuff. You should have bought a 1500W generator." In fact the charger works fine at 750W continous but it appears to have a start up surge. I can get around the problem by turning the power down to 75% on the charger. The generator starts up the charger fine on this. I then turn up the power to 100% and it continues to run. But it is a bit of a pain to have to do this.

 

N

[MtB]

Currently (phnar phnar) my 24v domestic bank is at 23.2v according to the Tracer display.

 

Unusually low I admit, but when I fire up the genny in the morning I doubt the clamp meter will show more than 15A even for the first few mins.

 

 

(Spelleen eddit)

 

 

Just to tidy this up, I fired up the genny this morning with seriously flat batteries (23.2v) and the current delivered by my supposedly 20A charger was exactly 12 amps according to both my clamp meters.

 

On checking though, the specification of my Victron "Blue Power" 12-24 charger confusingly states max 24v charging current as "12A or 15A".

 

I'm wondering WTF that means!

[by'eck]

A word of caution.

 

I bought a Kipor ig1000 which has a npminal power output of 1000W. I bought it to power a 20A Sterling charger which was fine, except that it was taking far too long to charge the batteries.

 

I then bought a 50A Sterliong charger which has a advertised power consumption of 750W. As soon as the charger came on line it overloaded and tripped the gennie.I complained to Sterlng who basically said "Tuff. You should have bought a 1500W generator." In fact the charger works fine at 750W continous but it appears to have a start up surge. I can get around the problem by turning the power down to 75% on the charger. The generator starts up the charger fine on this. I then turn up the power to 100% and it continues to run. But it is a bit of a pain to have to do this.

 

N

 

Since the subject of powering mains chargers from suitcase generators comes up maybe too often this is a guide based on personal experience and that of others as to the minimum continuous rated generator output needed to power a range of mains chargers.

 

Charger Genny

20 amp - 600 watt

30 amp - 1kW

50 amp - 1.5kW

100 amp - 2kW+

 

Doubtless there will be some folk who have managed with less, but this gives a rough guide with margin for the sometimes quite high startup currents demanded by chargers.

[Mitchellmoxo]

I brought a 30a numax charger on eBay from ed Boden which arrived today. Now to connect it up & test once the new batteries have arrived