Battery power/requirements ?
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- May 16, 2021
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What Sargent system have you?
I like the Sargent System in terms of their power distribution and control panels, but their charging capability is woeful. I was getting a maximum of 10A from my EC325.
When I upgraded the Battery Bank to 300Ah, I bypassed the charging features of the Sargent entirely - fitted a 60A B2B and a 70A Mains Charger.
Sargent is the make of my onboard mains charger.
The model is Sargent PX - 300 Intelligent Battery Charger.
I'm guessing my split charge system (no idea what it is) doesn't deliver more than 10 amps, maybe less, so if I have a night off grid and use say 40 amps then unless I then drive for at least 4 hours plus I am going to need to use the EHU to fully charge the leisure batteries.
The model is Sargent PX - 300 Intelligent Battery Charger.
I'm guessing my split charge system (no idea what it is) doesn't deliver more than 10 amps, maybe less, so if I have a night off grid and use say 40 amps then unless I then drive for at least 4 hours plus I am going to need to use the EHU to fully charge the leisure batteries.
TheBig1
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It is recommended that the mains charger should be at least 10% of the battery capacity. So a 100ah battery needs 10amps and a 200ah bank 20amps. Working a 10a charger flat out will do it no good
mikebeaches
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Personally, I'd stick with the single battery for now.
If it's in good condition as you indicated, you'd be fine for a few days off-grid, with the possible exception of using the TV for any length of time.
If it were me, I'd suck-it-and-see before worrying about the cost and time of buying and installing a second battery.
Just my opinion.
We've always been perfectly fine with a single leisure battery.
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The mains charger is 25 amps.
I think you will find that was the current from the charger rather than battery volts if you add another battery you will only get the power equivelant of the reduced condition of the year old battery as far as inverter use you need in general something like 2000 amp with1000 watt constant capacity what is the power usage if your tv
I have only had this MH for 2 months and only used it on EHU so far.
I previously had a PVC for 5 years.
I occasionally off gridded in the PVC.
That had a twin leisure battery set up with a split charge and mains charger for when on EHU.
The system worked fine giving no problems.
My electrical usage/consumption in the MH will be the same as it was in the PVC so I am setting the electric supply up the same.
My TV is 45 watts on mains.
I reckon my electric usage will be around 35-40 amps for a day off grid.
The resting voltage of 12.97v was with the MH having sat for 2 weeks unused and not hooked up to the mains so it was the battery voltage not the voltage from a charger.
I previously had a PVC for 5 years.
I occasionally off gridded in the PVC.
That had a twin leisure battery set up with a split charge and mains charger for when on EHU.
The system worked fine giving no problems.
My electrical usage/consumption in the MH will be the same as it was in the PVC so I am setting the electric supply up the same.
My TV is 45 watts on mains.
I reckon my electric usage will be around 35-40 amps for a day off grid.
The resting voltage of 12.97v was with the MH having sat for 2 weeks unused and not hooked up to the mains so it was the battery voltage not the voltage from a charger.
Did you have an inverter in the PVC?. I would have thought even allowing for inneficient conversion and a higher start up current you won't need a huge invertor. If you get a smaller one I would put a TV only sticker on it
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OK so back to the wiring of the batterys together and the inverter, if I remember my basic schoolboy electrics correctly, if you have a 1000w inverter it could peak at 2000w so that means 2000w ÷ 12v = 167Amps (volts x amps = watts) so you will need a minimum of 170 amp cables (25mm² I think ) and 200A fuses!
Why would a 1000 watt inverter peak at 2000 watts when having a 45 watt draw on it ?
As it happens the inverter I have for the MH is 500 watts continuos 1000 watts peak.
Again it will only have a 45 watt draw applied to it
As it happens the inverter I have for the MH is 500 watts continuos 1000 watts peak.
Again it will only have a 45 watt draw applied to it
So you design for safety and ensure the cables are capable of supporting the inverter at max load not a nominal load. When electrical appliances first start up the initial draw can be twice that of the running ampage.
The inverter is 500w peaking at 1000w so the cables that supply it must be capable of supporting the max 1000w.
So 1000w ÷ 12 volts = 83 amps
The cables need to be minimum 16mm² (110A max) with 85Amp fuses.
W
The inverter is 500w peaking at 1000w so the cables that supply it must be capable of supporting the max 1000w.
So 1000w ÷ 12 volts = 83 amps
The cables need to be minimum 16mm² (110A max) with 85Amp fuses.
W
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Beast
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- Jul 9, 2019
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Yes plenty but tv can suck it up,, next time at home safe , turn on tv lights etc and time it to give you some idea..,, ps for the cost of solar it’s FREE energy.
Second post changes everything. Expect a very low battery in the morning depending on the amount of TV time so a long drive probably necessary. Sooner you get a second battery fitted and some solar, the happier you will be.
Forgive me if I'm being ignorant here but isn't the above true only if you place a 500 watt draw on the inverter ?
If you place a 45 watt draw on the inverter then on start up the initial draw could be twice the running amperage ?
45 watts is a little under 4 amps so on start up the initial draw could be about 8 amps quickly settling down to about 4-5 amps given the inefficiency of a converter ?
The 45 watt TV is the only item that will be run off the inverter.
Our inverter only uses 1.5 amps when the 24" TV is on, with energy saving mode on the picture is unnoticably darker 
I'm just going on the fact that the sticker on the back of the TV states 45 watts.
There is an eco mode but I have no idea what wattage that saves.
There is an eco mode but I have no idea what wattage that saves.
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- May 16, 2021
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If you intend to only ever use the TV for a 45W TV, then it could be worth considering getting a significantly smaller Inverter. The overhead of an inverter when switched on is pretty proportional to its capacity, which is why it is important to get the right inverter for the usage, not just the biggest one that can be found for the budget (which is what a lot of people seem to do).
I am assuming you mean 1.5A on the 12V DC system? If so, that is a remarkably (and dare I say it rather unlikely) low power consumption at just around 18W nominal including the inverter overhead. Where are you reading this 1.5A from? or is it the Inverter overhead that is 1.5A and separate from the actual TV power draw?Our inverter only uses 1.5 amps when the 24" TV is on, with energy saving mode on the picture is unnoticably darker
As a comparision, my Avtex 24" TV (running off DC) uses around 5A (of which a small amount will be the connected Firestick)
When I had my PVC, in which I ran a 24 inch mains TV from an inverter, I didn't upgrade the cabling or fuse, I just used what came with the inverter.
The leisure batteries were at the opposite end of the van to the TV so I used a 240v extension lead rather than extending the 12v cables.
The leisure batteries were at the opposite end of the van to the TV so I used a 240v extension lead rather than extending the 12v cables.
- May 16, 2021
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This is a general comment picking up on a point above .... it should be noted, sad as it may seem, that when an Inverter is supplied with DC Cables, they are very rarely up to the job if the inverter is used at its rated maximum. They tend to be undersized in gauge for one thing, and are often made from Aluminium rather than copper, and so have a lower ampacity for that size compared to copper (and if anyone looks up cable gauges vs current, the tables are always based on OFC, not the inferior Aluminium). Put those two points together and it is a sorry situation
Very rarely have I ever used the supplied cables with an inverter as they tend to be just rubbish basically. The Victron EasyPlus and EasySolar are the only ones with "real" cables supplied as standard and they fit 35mm welding cable for those 1300W Inverters.
My PVC inverter was 1000 watt continuous 2000 watt peak.
I only ran a 45 watt TV off it so I assume the cables were more than capable of running about 4 amp continuous 8 amp peak as I ran it for 5 years with no problems.
I only ran a 45 watt TV off it so I assume the cables were more than capable of running about 4 amp continuous 8 amp peak as I ran it for 5 years with no problems.
I assume that the cables supplied with this 500 watt continuous, 1000 watt peak inverter will also handle the 45 watt TV fine.
If I was intending running say a microwave, electric kettle or other power hungry item I would get a bigger inverter and replace the 12v cables with significantly heavier ones.
If I was intending running say a microwave, electric kettle or other power hungry item I would get a bigger inverter and replace the 12v cables with significantly heavier ones.
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A good idea to fit the inverter as close as practical to the battery too as the 240v will need much thinner cables. I think you're looking at it the way I would there are a lot who will say you need at least 400w of solar two lithium batteries a b2b etc no matter what load you're putting on it.
Yes the inverter will be as close to the leisure batteries as I can get and I'll use a 240v extension from it to the TV.
If I was intending to do much off grid then solar, lithium's and B2B would be the way to go.
However I will only be doing the very rare night off grid, probably only a couple of times a year, so a second lead acid LB will be more than enough to cope with my needs (could probably manage with just one LB in reality).
I can't justify, nor do I need solar, lithium's, B2B for a couple of nights off grid a year.
If I was intending to do much off grid then solar, lithium's and B2B would be the way to go.
However I will only be doing the very rare night off grid, probably only a couple of times a year, so a second lead acid LB will be more than enough to cope with my needs (could probably manage with just one LB in reality).
I can't justify, nor do I need solar, lithium's, B2B for a couple of nights off grid a year.
It is low isn't it. I've just been out to check again. 1.7 amps on the battery monitor and 1.68 amps on the actual inverter feed.
TV
Battery monitor top rightI suppose it helps to have the finest Swiss made inverter money can buy
The inverter overhead is 0.2A
No it's just some free cable I got out of a skip
I put some red sleeving on it I think.Subscribers do not see these advertisements
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