Best inverter for charging on-board batteries?

LandVan · 12-22-2016, 08:27 AM

Does anyone have a suggestion about a good inverter for charging batteries on board the SMB?

I am thinking about getting a 300W inverter hard-wired to my truck battery to charge other batteries while driving long distances.

1der · 12-22-2016, 08:31 AM

What kind of batteries are you looking at charging?

LandVan · 12-22-2016, 08:40 AM

Quote:

Originally Posted by 1der

What kind of batteries are you looking at charging?

I have a few of these portable batteries (Jump Starters - CAT) that I use for power tools and my trap shooting machine.

I am trying to figure out if I can recharge them while driving.

1der · 12-22-2016, 09:17 AM

Got it. Each CAT unit will require about 300 watts to charge based on 120v/ 2 amp charger. You may be better off going with a quality 750 to 1000 watt inverter with proper gauge cables to handle the current.

We have a small Samlex 450 for light loads. It works fine but the annoying fan turns on with any load above 150w. Turns out it is designed that way. Meanwhile our larger Samlex pure wine wave 2200 watt inverter, the fan almost never turns on. Check the fine print on whichever inverter you get to see what it says about the fan.

Also, see if the power packs need/ prefer pure sine wave for charging.

DonRowe.com has a fine selection of inverters and chargers.

LandVan · 12-22-2016, 09:23 AM

Quote:

Originally Posted by 1der

Got it. Each CAT unit will require about 300 watts to charge based on 120v/ 2 amp charger. You may be better off going with a quality 750 to 1000 watt charger with proper gauge cables to handle the current.

We have a small Samlex 450 for light loads. It works fine but the annoying fan turns on with any load above 150w. Turns out it is designed that way. Meanwhile our larger Samlex pure wine wave 2200 watt inverter, the fan almost never turns on. Check the fine print on whichever inverter you get to see what it says about the fan.

Also, see if the power packs need/ prefer pure sine wave for charging.

DonRowe.com has a fine selection of inverters and chargers.

Great info, thanks. I am not proficient with the conversion math.

LenS · 12-22-2016, 11:08 AM

Charger or Converter charger: for charging batteries. We have Progressive Dynamics 9245 with Charge Wizard. At least for wet cell batteries the rule of thumb is charger is sized to ~20% of capacity. We have two golf cart 6v batteries rated at ~900Ah...so 20% indicates about a 45A charger. We got the 45A Progressive Dynamics.

Inverter is not for charging but for changing 12v DC into 120v AC. We have a PROwatt SW Series 1000 features 1000 watts of True Sine-Wave AC output. It is marginal because our refrig start up current trips its low voltage alarm ( a few millisecond beep) when the house batteries are only 25% discharged and there is no published way to turn off the annoyance .

LandVan · 12-22-2016, 11:28 AM

Quote:

Originally Posted by LenS

Charger or Converter charger: for charging batteries. We have Progressive Dynamics 9245 with Charge Wizard. At least for wet cell batteries the rule of thumb is charger is sized to ~20% of capacity. We have two golf cart 6v batteries rated at ~900Ah...so 20% indicates about a 45A charger. We got the 45A Progressive Dynamics.

Inverter is not for charging but for changing 12v DC into 120v AC. We have a PROwatt SW Series 1000 features 1000 watts of True Sine-Wave AC output. It is marginal because our refrig start up current trips its low voltage alarm ( a few millisecond beep) when the house batteries are only 25% discharged and there is no published way to turn off the annoyance .

My Power Packs plug right into the wall at home with a standard 3 prong plug so I don't need a battery charger.

I think I just need a constant power source (properly sized)to recharge the pack(s) on long drives. Hopefully, I can get it done with an inverter.

1der · 12-22-2016, 12:58 PM

Yes, for what you are wanting to do, a properly sized inverter will provide the 120v needed to plug in the CAT PowerPak charger.

One point to keep in mind - 2 amps at 120v is 20 amps at 12v. For two CAT's at the same time plus inherint losses, you will be drawing upwards of 50 amps at 12v. That is significant and you will probably want the engine running at 1000 rpm or higher.

Econoliner · 12-22-2016, 03:32 PM

There's a pretty good deal right now at Lowes (of all places) on inverters. They have had some of the Zamp pure sine models on sale for the past few weeks for around 60% off. I picked up a 600W for $79.58. That's a premium brand, pure-sine wave inverter. Amazon has them for $200+. I think they still have the 1000W pure-sine version for $131.60. Current Amazon price is $326.00. I heard about them on the Airstream forum.
I tested mine with a moderate load and it was producing 118VAC with a beautiful sine wave on the O-scope. "Modified sine-wave" inverters have nothing to do with sine-waves...they put out square waves with tons of harmonics. Just my opinion. Results may vary.

LandVan · 12-22-2016, 03:42 PM

Quote:

Originally Posted by Econoliner

There's a pretty good deal right now at Lowes (of all places) on inverters. They have had some of the Zamp pure sine models on sale for the past few weeks for around 60% off. I picked up a 600W for $79.58. That's a premium brand, pure-sine wave inverter. Amazon has them for $200+. I think they still have the 1000W pure-sine version for $131.60. Current Amazon price is $326.00. I heard about them on the Airstream forum.
I tested mine with a moderate load and it was producing 118VAC with a beautiful sine wave on the O-scope. "Modified sine-wave" inverters have nothing to do with sine-waves...they put out square waves with tons of harmonics. Just my opinion. Results may vary.

After checking all morning, that would be a great deal. I will check it out. Thanks.