# Mecer 2400VA Inverter (Community Support)

#### Gtx Gaming

##### Gtx Gaming
Is the 10A recommendation for 2 batteries or for 1?

What amp does the 700W Mecer charge 1 battery at I wonder
Mecer 720watt can do 10a and 20a charging.

#### wingnut771

##### Executive Member
But if im correct due to 12v now and not 24v, the equation shows that less hours are gained on the battery?
Example: side note, i suck at math
12x180ah(one 12v batt)/wattage 650/2 x0.85=1.412
24x180/650/2x0.85=2.824
now that you only have one battery, you should double it's size to compensate because you're coming from 2 batteries to make 24V.
you were getting 2 x 150ah, now only 1 x 180ah, you should be getting 1 x 300ah battery to get the same use out of 12v.
24V x 150ah (2x12V150ah)=3600 watt hours (remember, parallel batteries, voltage doubles, current stays the same)
12V x 150ah (1x12V150ah)=1800 watt hours (here you would do series (if you can't find a big enough battery) and add batteries which keeps the volts the same but doubles current)

one thing to note going 12V is more current where:
700W @ 24V = 700 divide 24 = 29.16666666666667 amps from your battery.
now 700W @ 12V = 700 divide 12 = 58.33333333333333 amps from your battery.

so you can see there is more load on the battery which will shorten the amp hour rating:

"A 1C rate means that the discharge current will discharge the entire battery in 1 hour. For a battery with a capacity of 100 Amp-hrs, this equates to a discharge current of 100 Amps. A 5C rate for this battery would be 500 Amps, and a C/2 rate would be 50 Amps. Similarly, an E-rate describes the discharge power. "

Think you'll need at least a 300ah battery @ 12V and thicker battery cables and bigger fuse.

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#### wingnut771

##### Executive Member
Is the 10A recommendation for 2 batteries or for 1?

What amp does the 700W Mecer charge 1 battery at I wonder
for 1 battery i think.

#### wingnut771

##### Executive Member
Yes, you have more energy on the 24V system than the 12V.
because of 2 batteries vs 1 battery.
if you spec the 1-battery system's battery double the size of one of the 2-battery system's batteries then it's the same energy.

#### wingnut771

##### Executive Member
Mecer 720watt can do 10a and 20a charging.
all i'm saying is lead acid likes low and slow charging. i guess if you have 4 batteries hooked up then 20A is fine.

#### Leno

##### Expert Member
Yeah its mainly as in PE we have 12 hours on average for stage 3 and then there is not enough time between to charge, so ill give 20A a try, maybe only if its stage 3

Edit: just to clarify I have 2x 105 Ah batteries

#### Gaz{M}

##### Executive Member
Yeah its mainly as in PE we have 12 hours on average for stage 3 and then there is not enough time between to charge, so ill give 20A a try, maybe only if its stage 3

Edit: just to clarify I have 2x 105 Ah batteries
20A is way less than what 2 x 105ah can handle. Go for it. Why suffer needlessly.

#### Azg

##### Expert Member
Does any one have any experience / review for this inverter + battery:

#### Verde

##### Expert Member
But if im correct due to 12v now and not 24v, the equation shows that less hours are gained on the battery?
Example: side note, i suck at math
12x180ah(one 12v batt)/wattage 650/2 x0.85=1.412
24x180/650/2x0.85=2.824
I assume you are looking at 12V batteries.
So for a 24V system you need 2 x 12V batteries
In series the voltage is doubled, the capacity stays the same so 2x12V180Ah =2x12Vx180Ah/2x.85/650 = 2.8Hr
In parallel the voltage stays the same and the capacity doubles so 2x12V180AH = 12Vx2x180Ah/2x.85/650 = 2.8Hr

#### COMPUTEK

##### Executive Member
So my new updated question is
What are my battery needs on a 12v inverter to run 2-3hours at 650watt
I've posted this before, but use this to do your own calculations

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#### thechamp

##### Honorary Master
I assume you are looking at 12V batteries.
So for a 24V system you need 2 x 12V batteries
In series the voltage is doubled, the capacity stays the same so 2x12V180Ah =2x12Vx180Ah/2x.85/650 = 2.8Hr
In parallel the voltage stays the same and the capacity doubles so 2x12V180AH = 12Vx2x180Ah/2x.85/650 = 2.8Hr
If he uses two batteries in the 12V system.

#### COMPUTEK

##### Executive Member
now that you only have one battery, you should double it's size to compensate because you're coming from 2 batteries to make 24V.
you were getting 2 x 150ah, now only 1 x 180ah, you should be getting 1 x 300ah battery to get the same use out of 12v.
24V x 150ah (2x12V150ah)=3600 watt hours (remember, parallel batteries, voltage doubles, current stays the same)
12V x 150ah (1x12V150ah)=1800 watt hours (here you would do series (if you can't find a big enough battery) and add batteries which keeps the volts the same but doubles current)

one thing to note going 12V is more current where:
700W @ 24V = 700 divide 24 = 29.16666666666667 amps from your battery.
now 700W @ 12V = 700 divide 12 = 58.33333333333333 amps from your battery.

so you can see there is more load on the battery which will shorten the amp hour rating:

"A 1C rate means that the discharge current will discharge the entire battery in 1 hour. For a battery with a capacity of 100 Amp-hrs, this equates to a discharge current of 100 Amps. A 5C rate for this battery would be 500 Amps, and a C/2 rate would be 50 Amps. Similarly, an E-rate describes the discharge power. "

Think you'll need at least a 300ah battery @ 12V and thicker battery cables and bigger fuse.
you have this completely wrong

#### joshuatree

##### Expert Member
Is this site legit?

#### Gtx Gaming

##### Gtx Gaming
Is this site legit?

Its on back order, so not worth it anyway. All the stock comes from mustek, but seems pclinkshop is getting first dibs on the stock.

#### Verde

##### Expert Member
If he uses two batteries in the 12V system.
If he wants to get through load shedding using 600W/Hr he will need 2 150AH 12V batteries on both a 12V and 24V system.

#### djbrendan

##### Expert Member
I've posted this before, but use this to do your own calculations
Nifty little excel. Thanks

#### RedViking

##### Nord of the South
I've posted this before, but use this to do your own calculations
Is it safe for work?

#### djbrendan

##### Expert Member
If he wants to get through load shedding using 600W/Hr he will need 2 150AH 12V batteries on both a 12V and 24V system.
Either way it seems yea, or one big ass battery like a 300ah

#### thechamp

##### Honorary Master
Either way it seems yea, or one big ass battery like a 300ah
Don't put all you eggs in one basket.

#### djbrendan

##### Expert Member
Don't put all you eggs in one basket.
good point,
so still go for two units. If one kaks i still have a back up on a 12v inverter.