24v 2000w pure sine wave inverter 4000w surge

[russ]

My guess is that going below 24 volts repetitively will cause one or more of the cells in that system to have an early failure.

Hope it works out for you.

Not to worry - when he smokes the entire thing we will laugh at him. Of course he will never mention it but just hide.

There are such things as proper engineering practices - things that he has no idea about.

[Wakie]

Is this a typo? A 24V inverter won't work at 12V

sorry i just write 12.3 after i divide 24.6 in my head
my system is 24 v with 200 ah battery (4 battery in serie parallele to make 24 v)
my battery is rv battery not true deep cycle

[mschulz]

ah thanks, so i really need a 500ah battery bank to do loads of 1500w for a c/8 discharge rate. my 200ah battery bank can do just 600w load. got it. so i will need to use my 7 panals to get my 500ah battery bank. so untill then my coffees will have to wait till the midday sun on a full battery bank. dang, looks like i will have to start the gen in the mornings

ok been thinking, to expand this on the cheap, i use 4 x 12v 100ah batteries, do 2 sets of 2 x 12 batteries in parallel, then configure these 2 sets in series to get a 24v battery bank of 400ah. put up another 3 x 250w panels in parallel same as the existing set of 3 panels in parallel. then i only need one more chi-com 30amp CC . so that will be 2 x chi-com 30amp CCs and have them both in a 24v series charge config. i should get away with a 400ah battery bank just like Wakie does

You know, a good habit to get into if you do not want to buy a **** ton of batteries. Just before you start the coffee maker, crank up the generator. Run the coffee maker off your generator along with a battery charger. This will not tax you system while making coffee and give those batteries a boost from their Discharge during the night. Allows you to get away with a smaller battery bank and keeps those batteries happy.

[Bala]

when i say i picked up a new inverter "cheap" i wasnt saying the product was crap. it was on special and is not "cheap" in australia there are regulations concerning electronic products so when buying from retail stores you can buy with confidence

Sadly meeting Australian standards for any product does not indicate quality, and I have no doubt it is the same in any country. For an inverter it may pass safety requirements, but this does not mean the internals of the unit will be able to run at specified rates without over heating etc etc.

just look at all the cheap power tools avail, many were, are safe, double insulated, but some motors burn out in minutes, some last.

Inverter suppliers could probably use this,

Please note: Australian standards currently apply only to inverters rated up to 30kW. GC Inverters listed in the >30kW category may not be certified to any relevant Australian standards, but have received (as a minimum) an EC Declaration of Conformity stating compliance to IEC 62109 and/or VDE-AR-N-4104. - See more at: https://www.solaraccreditation.com.a....dJBnctZm.dpuf

I got that info form here, not saying it is true or false, but looks legit.

IMO Good quality inverter manufacturers would likely find standards from Eu, US and Aus and get there units certified to them.

[almac]

Not to worry - when he smokes the entire thing we will laugh at him. Of course he will never mention it but just hide.

There are such things as proper engineering practices - things that he has no idea about.

there are such things as not judging people that you have no idea about.

i value the experience of the members here and so far have shared mine openly... including toasting a voltmeter on my solar panels. no i did not hide!!! made another coffee this morning batteries went down to 24v this time, the solar panels were backing them up though. turns out Wakie is also using a 200ah battery bank and using even more watts than me 1500w for 5mins after he corrected his earlier mistake. apprieciate the sharing of knowledge from sunking and others thankyou. im merely making the most of what i have now , i read on another thread you can use 2 charging sources on the one battery bank? was thinking of running another 3 x 250w panels with a seperate charge controller to expand the battery bank to 400ah

[Sunking]

so untill then my coffees will have to wait till the midday sun on a full battery bank. dang, looks like i will have to start the gen in the mornings

Maybe, maybe not.

What I am trying to tell you is when your battery is undersized for the load, expect problems. As you noted in your test the conditions were right, and you can got away with it. Try that on a less than fully charged battery and you will get a different result.

To be able to operate your Inverter at full power at any time requires the battery to be sized correctly. When your battery is undersized, you can get away with putting a large load on it for a brief period of time.

But to do it right, size the battery properly. That way you can run full load anytime you want and run continuously until the battery is discharged. Think of it this way. Sure you can push your car a block on a flat level paved surface with good tire pressure, and you are fully rested. But you cannot push it to work or in mud. For that you need to start the dam engine stupid.

[almac]

been using this setup making coffees everyday now. even on a discharged battery in the morning on a cloudy winters day. still working no prob. the 1350w at 24v is 56amps? really not that much for a 200ah battery to sustain for 2mins. deep cycle batteries are used by some as cranking batteries. isnt that like 500amps discharge? iv read some threads where they have been used as starting batteries and have lasted for years, they say a deep cycle battery as a cranking battery needs to be a bit bigger than a cranking battery to do the same job

[Bala]

I used two deep cycles in parallel in one of my 6cyl diesel landcruisers and they lasted for years, that is a totally different situation to what you are doing. in the vehicle they are kept fully charged all the time and just put out the split second burst to start.

I have basically said the following before but will say it again,

I think you are yet to understand what is a fully charged battery and depth of discharge and cycles for life.

If you have not purchased a hydrometer and understand how to use it then you dont know what you are doing to those batteries and their life may well be counted in months not years.

You can basically run anything hard, or for a long time,

But you generally cant have both, and if you dont have the correct maintenance program in place you wont get the long time.

[almac]

I used two deep cycles in parallel in one of my 6cyl diesel landcruisers and they lasted for years, that is a totally different situation to what you are doing. in the vehicle they are kept fully charged all the time and just put out the split second burst to start.

I have basically said the following before but will say it again,

I think you are yet to understand what is a fully charged battery and depth of discharge and cycles for life.

If you have not purchased a hydrometer and understand how to use it then you dont know what you are doing to those batteries and their life may well be counted in months not years.

You can basically run anything hard, or for a long time,

But you generally cant have both, and if you dont have the correct maintenance program in place you wont get the long time.

hi thanks, ok i will get a hydrometer. but i do understand the batteries need to be fully recharged. every couple of days i put them in parallel and run a 12v 16amp 3 stage charger off the generator till they are full. this sometimes can take 6hrs. by charging them in parallel they will both be fully charged by the time the charger registers them as full. then i put them back in series in a 24v config to the inverter and solar charge controller. lately is been cloudy every day so have been using the 3 stage charger more often,

my understanding about charging off a car alternator is a deep cycle battery cannot be fully charged by an alternator

[Sunking]

my understanding about charging off a car alternator is a deep cycle battery cannot be fully charged by an alternator

You would be mistaken.

SLI (Starting-Lighting-Ignition) aka Cranking batteries are an alloy of Lead-Calcium in both positive and negative plates. Calcium lowers internal resistance. In addition to Calcium SLI battery plates are thinner allowing more plates in a given area thus lowering internal resistance even lower. The lower resistance greatly improves Cold Cranking Amps and Cranking Amps. SLI battery plates do not extend into the bottom of the battery jar to allow room for flaking plates and corrosion to build up. This is because vehicle alternators and Calcium batteries require slightly higher charging voltages and the higher voltage causes corrosion and plate flaking. If the plates go all the way to the bottom, there is a good chance of the debris shorting out the battery. Lead Calcium batteries do not like deep discharges, and become resistant to recharging. SLI batteries will not have an AH or RC ratings, only CCA, CA, and MCA if for Marine application.

Deep Cycle batteries are made from Lead Antimony alloy. The have fewer plates, but are thicker and heavier and completely fill the battery jar. They are acceptable to deep discharges but have higher internal resistance. Deep Cycle batteries will only have AH and sometimes RC ratings. If you see CCA, CA, or MCA it is not a Deep Cycle battery.

Then there are Hybrid Batteries and they come with various Marketing names like Golf Cart, RV, Marine, Leisure, Troiling, and half a dozen other names I cannot think of. A Hybrid has Lead-Antimony positive plates for deep cycling, and Lead Calcium negative plates for lower internal resistance. Their plates are heavier and thicker than SLI batteries to give them some cycle life, but not as thick and heavy as Deep Cycle so they do not get the cycle life performance of Deep Cycle batteries. They provide higher currents than Deep Cycle but not as much as SLI. Hybrid batteries will have specs of CCA, CA, MCA, RC, and AH trying to be all things.

For folks who have RV can easily charge their Hybrid Batteries or Deep Cycle batteries from their alternators byy using an electronic isolator. The Isolator lowers the voltage. Well I should say the better isolators do that.

[Bala]

The alternator in a car has a regulator with a set V. if does not do a bulk absorb float like a solar CC.

It is designed to replace smaller amounts of capacity after starting and to keep a fully charged battery fully charged.

They will recharge batteries that are well down but not in a short time.

if you use your battery all night to run your fridge etc, then drive all day then do the same all will be well.

If you use your battery all day and night for days on end to run the fridge and lights and only start the car for 1/2 an hr each day then you are losing the battle.

You can get smart regulators, or set up dual regs with switching to fast charge your Aux battery, if your really keen.

When remote camping in hot climates, how to keep the fridge cold is the most talked about camp topic.

A lot think running the car 1/2 and hr each day will top up the battery. it will generally keep the fridge running but battery life is very short due to the the low DOD cycling.

[inetdog]

The alternator in a car has a regulator with a set V. if does not do a bulk absorb float like a solar CC.

It is designed to replace smaller amounts of capacity after starting and to keep a fully charged battery fully charged.

They will recharge batteries that are well down but not in a short time.

Those two statements are contradictory. The alternator can supply as much as 50A and likely more for battery charging.
Quickly replacing charge used in starting is the same capability needed for complete recharging in a short time.

[Bala]

Those two statements are contradictory. The alternator can supply as much as 50A and likely more for battery charging.
Quickly replacing charge used in starting is the same capability needed for complete recharging in a short time.

I just said it would replace charge used in starting, you added quickly

Regulator V settings and Voltage drop from reg to battery vary quite a bit from makes and models.

[Sunny Solar]

I just said it would replace charge used in starting, you added quickly

Regulator V settings and Voltage drop from reg to battery vary quite a bit from makes and models.

Only about 100 to 200mv at most.. and it becomes not very relevant in normal use. And you cant alter the reg settings anyway..

[Bala]

Only about 100 to 200mv at most.. and it becomes not very relevant in normal use. And you cant alter the reg settings anyway..

Older vehicle charge rate specs were normally 13.5v to 14.5v, some newer vehicles are running more. One of my motorbikes is spec at 14.5 to 15.5.

To meet latest emission standards some have variable alternator charging controlled by the ecu and temp compensation that will drop V to 13.2.

I have had a Kenworth truck at work that had 14.2 off the back of the alt and 13.8 at the batteries, so V drop needs to be checked.

For some you can but special fuses fitted with a diode ( i believe) that fits in the alternator V sense wire. If basically fools the alt into thinking the battery V is low by about .5V so raises the charge rate.

I honestly dont know all the tech details. But I do know that if you want to charge batteries that are low on charge, fairly quickly, from the engine alt, then you need to make sure you know what your alt is doing and that the set up is correct. Just as you do for a Stand alone solar system.