Inverter settings

[dom88]

I live in a house with a recently updated system which comprises the following:

a 16kva generator, 10 solar panels, 12 1350a/h batteries and a trace inverter. 24v.

We recently had the house rewired due to some previous very risky installations. Whilst rewiring, the electrician accidentally reset the inverter settings. I have re-implemented as best i can remember but have received conflicting advice from various sources locally so thought i would throw this out there for the forum. My specific questions are as follows:-

1. Max battery charge? Currently set to 10amps, but i have the power for a lot more - is there a good reason to not increase this to 15amps? Obviously this would make charging quicker and require less generator time.
   
2. Bulk charge setting - currently set to 31 - I am sure it was 28.8 before?
   
3. Equalization setting - currently set to 28.8 - I thought an equilization required overcharging the batteries - my instinct is Bulk and Equalization settings here are the wrong way round?
   
4. Generator Max run time - any reason to set this to 10 hours? WHy have a limit at all?
   
   

Thanks very much for your assistance.

[commanda]

Depends on exactly what your definition of battery is. You state "12 1350a/h batteries". Is each battery a single 2 volt cell? If it is, then you have a 24 volt 1350 AH Battery. 12 * 2 volt cells (in series) makes 24 volts. The total capacity is commonly known as "C". Maximum charge and discharge rates are commonly expressed in fractions of "C". C/10 and C/20 are commonly quoted as discharge rates for specifying actual battery capacity. These same ratios are not unreasonable to be used for charging ratios as well.

For instance, a 1350 AH battery pack would take 10 hours to charge at the C/10 rate, and 20 hours at the C/20 rate. The C/10 rate in this case would imply 135 amps, and C/20 62.5 amps. It would take 135 hours to charge said battery pack from dead flat at 10 hours. That's 5 1/2 days at 10 amps. (yes this is simplified and ignores conversion losses in the batteries).

So, in answer to question 1. 62.5 amps would not be unreasonable.

My dump load controller is set to start dumping at 27 volts normally, and 28 volts when in boost or equalisation mode.

Eq at 28.8 is not unreasonable. Bulk charge should be a lot less than 31. 27 point something sounds good to me.

Generator run time needs a whole lot more inputs related to battery state of charge, current load, future short term load, current and short term future generating capacity outside of the generator. In short, a really big crystal ball.

hope that helps.

Amanda

[halfcrazy]

ok assuming these are 2 volt battery's you can charge them from 67 amps dc to 135 amps dc so the trace inverter charges at around 3.5 amps dc per amp ac so question 1 would be 19 amps ac up to 38 amps ac

question 2 bulk on a lead acid battery is usually around 28.8-29.2 but by all means list the manufacturer of the battery and i can give you an exact number

question 3 equalization charge is usually around 31 volts but again battery make will allow me to give an exact number.

question 4 generator max run time i think something in there is a good idea in case you aren't home and generator starts and something goes wrong say breaker trips somewhere the trace will eventually shut it down i usually set it to a little more then the average time i need generator to run

hope this helps get back to us with the battery manufacturer and model and we can give you all the specifics  

[dom88]

thanks for the comments, i will go and check the manufacturer and repost.

[dom88]

hi

the batteries are 2v Hawker brand.

hope this helps.

NB, might be asking a bit much here, but i note also my float settings are set to 27.2 - that also looks odd, i'm sure it used to be 28.8...

once again, thanks for the assistance.