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General Category => General Discussion => Topic started by: alyaz on October 24, 2018, 11:09:31 AM

Title: Neighbour’s Honda 3000 gen...
Post by: alyaz on October 24, 2018, 11:09:31 AM
Neighbour knows even less than I do (scary) and asked how many amps his Honda 3000 will charge his batteries at.  That was after he told me his batteries are toast and I had asked him how long he had his absorb set for and at what voltage.  I know he has a Magnum inverter and some older Rolls S460’s or something like that - FLA’s.  I looked online and see that a Honda 3000 puts out about 23 amps AC... 
Title: Re: Neighbour’s Honda 3000 gen...
Post by: ClassicCrazy on October 24, 2018, 11:56:31 AM
It doesn't matter how many amps the generator puts out - the important thing is to set the maximum DC charging amps in the inverter charger  to the max the batteries manufacturer recommends for bulk . If the generator won't put out that much then no issue either.    The absorb voltage , absorb time, temp compensation, float voltage are set in the inverter charger so it will act pretty much the same as the Classic would when it charges. I set mine a bit lower since I just use the generator / inverter charging to take up the bulk and some of the absorb on extended cloudy days and then let the PV and Classic finish it off.

Larry
Title: Re: Neighbour’s Honda 3000 gen...
Post by: alyaz on October 24, 2018, 12:23:29 PM
So how big of a generator is required to get his Magnum inverter/charger to provide a bulk/absorb of about 30v?  The question(s) I started asking myself was how do you ‘properly size’ a generator and how do you know if the Honda 3000 is large enough?
Title: Re: Neighbour’s Honda 3000 gen...
Post by: Vic on October 24, 2018, 03:05:54 PM
Hi Al,

Am not at all familiar with the Magnum Inverter/Chargers.

Flooded S-460s have a 20 hour Capacity of about 350 Ah when new.   If there is a single string of these batteries,  one would like to have about 10% of the 350 Ah C (about 35 Amps) as the minimum charge current capability.   Usually,   FLA batteries would not like to see more than about 13% of C as the maximum charge current (about 45 A,  per string).

Most of these Inverters  use an AC input Amps setting to govern the maximum charge current in Bulk.   So,   many 24 V  inverters would need a battery charge current setting of the DC battery current divided by 5.   Often there is another AC current setting for the maximum current taken from the genset.

Like most all of these inverter/chargers,  the Magnum probably uses the electronics of the inverter,   backward,  to do the battery charging (Bi-directional design).  This would mean that there is an internal transfer switch that automatically transfers the loads that are normally supplied by the inverter,  to the AC output of the genset.  SO,  the genset must be able to supply both the AC  loads,   and the charge current required by the battery.

A single string of S-460 could require as much as about 1600 watts of AC power at maximum current,   counting efficiency losses.

Believe that you and your neighbor are near sea-level,   so there should be no derating for genset altitude.

IMO,   seems that the Eu3000  is sized OK for some loads,  plus battery charging.  Although larger loads  --  Microwave,   larger pump etc might be too much for the genset   ...   all depends.   Some load-shedding might be necessary before starting the genset.

Yes,   you are correct,   the Eu3000  is rated at about 23 A AC at 120 V (it is not split-phase).

Again,  I have no personal experience with Magnum inverters.   FWIW,   Vic
Title: Re: Neighbour’s Honda 3000 gen...
Post by: alyaz on October 24, 2018, 04:31:31 PM
Thanks gang.

Yes both this neighbour and another are having to dial back the inverters so that they are only putting about 30% to the charger.  Both have Honda 3000’s and both find the generator going into a fault mode otherwise.
Title: Re: Neighbour’s Honda 3000 gen...
Post by: mike90045 on October 24, 2018, 07:45:55 PM
Depending on the system loads, power factor of motors, and what your battery charging needs are, you have to properly plan a system. 
First, does the inverter accept 120VAC or does it need 240VAC ?

Then, what sort of time do you have to charge with ? Smaller generators charge slower than large gensets.
I ran for a week with a eu2000 at night, wired with auto-transformer, to run house and keep micro battery bank charged, and let solar do it daytimes.

In bad weather, when I have to run my 3kw genset, I charge for about 90min
Title: Re: Neighbour’s Honda 3000 gen...
Post by: alyaz on October 24, 2018, 08:46:25 PM
Copy thanks.

Being that the MS4024PAE is 120 / 240 VAC, and the Honda 3000’s are only 120, does that equate to only hooking to one leg of the inverter and being limited to about half of the charger capacity?  Or is that not how it works?

http://www.magnum-dimensions.com/product-inverter/4000w-24vdc-pure-sine-inverter-charger-ms-pae
Title: Re: Neighbour’s Honda 3000 gen...
Post by: DEinME on October 27, 2018, 08:57:31 AM
Quote from: alyaz on October 24, 2018, 08:46:25 PM
Copy thanks.

Being that the MS4024PAE is 120 / 240 VAC, and the Honda 3000’s are only 120, does that equate to only hooking to one leg of the inverter and being limited to about half of the charger capacity?  Or is that not how it works?

http://www.magnum-dimensions.com/product-inverter/4000w-24vdc-pure-sine-inverter-charger-ms-pae
Yes, hook the gen to only 1 leg. You've already discovered that you need to turn the inverter's charging amps down to prevent the generator from disconnecting itself.

That's if you're working with the eu3000i generators which are inverter-generators. Honda makes other 3000W generators that provide normal 120/240VAC.

I had an eu3000i before I installed this PV system which includes an MS4448PAE. The instructions for the inverter say turn the charging amps to half the default value, but I had to lower the charging amps further to keep the generator from disconnecting.
Title: Re: Neighbour’s Honda 3000 gen...
Post by: alyaz on October 27, 2018, 10:51:43 AM
Copy both neighbours have the 3000 ‘eu' / inverter models.  That’s what the neighbours are doing after learning the hard way.  They both seem to understand they need a larger more appropriate generator but neither want to spend the money.  Guess they will spend it on batteries instead ;-)

Title: Re: Neighbour’s Honda 3000 gen...
Post by: tecnodave on December 01, 2018, 04:31:57 PM
On the MagnaSine split phase units....

I have been using a MagnaSine MS-4024AE 120/240 volt split phase unit for a few years now.

It will output 105 amps @ 24 volts when both phases are driven but with the Honda 120 volt you can connect only one phase and the charge current will be about 52.5 amps.

The inputs MUST BE 180 degrees out of phase. You cannot connect two generators, or 2 legs of a three phase setup or connect single input to both phases.

I use an Onan Emerald 4  ( 4kw 120 volt ) generator connected only to phase 1 and never get too much current for the batteries.

I bought my MagnaSine used and do not have any way to program it,so only use default settings.

I am about 400-500 % over paneled (as to my use, not the controllers capacity) with about 4 kW of Sanyo multilayer crystals and 4 kW of Sharp NE-165 & NE170 so very rarely do my batteries go flat. I can withstand 5 days no input at all before I need to worry about running the generator.

David