XW5548 AC2 (generator) breaker size: Mike to the courtesy counter please

[hammick]

I have an XW5548 system and I'm using an MEP-802a 5kw genset. The genset has a 30a breaker. When I hooked all this up a few years ago Schneider told me to set AC2 on the inverter to 30 amps. However when I leave it at 30 amps I cannot get my genset to go above 55% load. If I up the AC2 to 45 amps I can run over 80% load.

Can I set AC2 to 45 amps or even 60 amps without worry? These 5kw military gensets are underrated and can easily run at 120%. I don't plan to do that but then again I don't want to wet stack my genset leaving AC2 at 30%.

Thanks Mike or anyone else in the know.

[Ampster]

Are you asking if you can put 60 Amps into an inverter that the inverter manufacturer recommends 30 Amps?

[hammick]

Are you asking if you can put 60 Amps into an inverter that the inverter manufacturer recommends 30 Amps?

No. My inverter can take 60 amps and the distribution panel that came with it prewired has a 60a breaker for the generator input. AC2 breaker size is a software setting on the inverter.

Schneider doesn't have phone tech support anymore so that is why I am asking Mike here. He has the same inverter and is an expert.

[extrafu]

I have a XW+ 6848 and I am pulling 130 amps to the battery. So from either AC1 and AC2, it's over 30A @ 240V - I've two generators.

So your 5KW genset won't be a problem - at 240V it's just over 20A.

[hammick]

I have a XW+ 6848 and I am pulling 130 amps to the battery. So from either AC1 and AC2, it's over 30A @ 240V - I've two generators.

So your 5KW genset won't be a problem - at 240V it's just over 20A.

Thanks. So any idea why setting the AC2 breaker to 30 amps as recommend limits the generator current going to the inverter? Just trying to understand my system better.

[extrafu]

For me, both AC1 and AC2 are set to 60A. The XW derates its charging current to an equivalent of 80% of the breaker setting. So if you set it to 30A, it should pull no more than 24A from your generator, or 5760 watts @ 240V. I don't know what you see lower readings.

[Mike90250]

First, when the genset is enabled, IT runs the loads and the inverter runs backwards - charging the batteries.

The genset is now carrying loads and charging batteries, so the XW needs to know what the genset rating is, so it does not overload when the toaster comes on and the batteries are still low. First the XW will throttle back on charging the battery and if the load is really large, the inverter and batteries will assist the genset. (That happens in less than a second when configured right.)

I think the XW does 2 internal deratings. Here's what I use for my 2 gensets:

////
Battery Bank Capacity 1000 A (1,000A makes for easy, direct conversion to charging amps,
mistakes are limited to AC2 & Generator Support amps limits)
Maximum Charge Rate 5-35 A

AC2 Breaker Size 18.5 A (each breaker is only @ 120V so both will add, this setting = a limit of 4680w, internally derated to 3744w)

Generator Support Enable Enabled
Generator Support amps 13.5 A (each breaker is only @ 120V so both will add, this setting = a limit internally derated to 2515w)
Generator Support PLUS Enabled

ST5 on Lister 6/1
AC2 Breaker Size 18.5
Generator Support amps 13.5


Honda EU2000i spec 13A 1600w cont, 2kw 30 min
AC2 Breaker Size 9.0
Generator Support amps 5.0

[hammick]

For me, both AC1 and AC2 are set to 60A. The XW derates its charging current to an equivalent of 80% of the breaker setting. So if you set it to 30A, it should pull no more than 24A from your generator, or 5760 watts @ 240V. I don't know what you see lower readings.

Thanks. I knew about the 80% and figured the inverter should still take 100% from the genset even with AC2 set to 30 amps.

I'm assuming you can't charge through AC1 and AC2 at the same time? Thought I read in the manual that one takes priority over the other.

[extrafu]

Thanks. I knew about the 80% and figured the inverter should still take 100% from the genset even with AC2 set to 30 amps.

I'm assuming you can't charge through AC1 and AC2 at the same time? Thought I read in the manual that one takes priority over the other.

Pretty sure I can't. My primary generator is on AC2 and my secondary (backup) is on AC1. Both are very powerful. The first one is a Kohler RESA 14KW (AC1) and the 2nd one (AC1) is a Caterpillar portable generator, 12KW. My AGS is connected on the primary generator (AC2). If AC1 sees power, it should turn off the generator on AC2 automatically through the AGS. It shouldn't happen since I manually start the 2nd generator but it could theoretically happen if my second generator is running (the Caterpillar) and the Kohler decides to do its monthly scheduled 30 mins run.

[hammick]

First, when the genset is enabled, IT runs the loads and the inverter runs backwards - charging the batteries.

The genset is now carrying loads and charging batteries, so the XW needs to know what the genset rating is, so it does not overload when the toaster comes on and the batteries are still low. First the XW will throttle back on charging the battery and if the load is really large, the inverter and batteries will assist the genset. (That happens in less than a second when configured right.)

I think the XW does 2 internal deratings. Here's what I use for my 2 gensets:

////
Battery Bank Capacity 1000 A (1,000A makes for easy, direct conversion to charging amps,
mistakes are limited to AC2 & Generator Support amps limits)
Maximum Charge Rate 5-35 A

AC2 Breaker Size 18.5 A (each breaker is only @ 120V so both will add, this setting = a limit of 4680w, internally derated to 3744w)

Generator Support Enable Enabled
Generator Support amps 13.5 A (each breaker is only @ 120V so both will add, this setting = a limit internally derated to 2515w)
Generator Support PLUS Enabled

ST5 on Lister 6/1
AC2 Breaker Size 18.5
Generator Support amps 13.5


Honda EU2000i spec 13A 1600w cont, 2kw 30 min
AC2 Breaker Size 9.0
Generator Support amps 5.0

Thanks for the detailed info Mike. I don't have generator support enabled as I don't have big enough loads to max out my genset. I did enable it today to see what would happen with AC2 breaker set to 30 amps. The inverter quit charging the batteries. So I guess I will set AC2 to 45 amps and call it good. Not sure why 30 amps didn't work but it doesn't really matter since I have fixed my problem. I may explore generator support further on the off chance my wife is running the washer and dryer, the well pump comes on and she decides to make toast and dry her hair

[hammick]

Hey guys on a somewhat related topic I plan to wire a 3650 watt genset into AC1 of my XW5548. I have the XW PDP. The 60a generator breaker that came in it is Square D. Can I use the Square D breakers sold at Home Depot or are these special Square D breakers?

Thanks.

https://www.homedepot.com/p/Square-D-Homeline-20-Amp-Single-Pole-Circuit-Breaker-HOM120CP/100045009

[hammick]

Nevermind. I ended up getting a Square D knife style disconnect. It takes old school Edison fuses.

I'm really impressed with the Firman generators. I bought the P03612. 3650 watts and 4550 surge watts. Remote electric start with remote choke. 5 gallon tank and wheel kit included. It's 68db but it actually sounds more quite in our living quarters than a 1600 watt Yamaha inverter. I think the inverter has a deeper sound that reverbs off our metal siding. The inverter would definitely be more quiet for RV use. The remote start is a great feature and it has a stator to charge the battery. It's on sale now at Home Depot for $399 which is the cheapest 240v remote start genset I've ever seen.