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Canibul · 09-04-2014, 06:48

I'm slowly working my way through the seemingly myriad issues in updating an old boat. One of the demons the previous owner left me was his complete and utter love for the high quality of Harbor Freight electronics. The boat came with one of their 2000/4000 watt inverters, along with a smaller one. I think it was 1000 watts. I don't know. It failed a month ago.

Now I'm looking at this remaining "Chicago" brand Harbor Freight 2000/4000 watt inverter and thinking to myself...."is a $89 inverter really going to perform for us in a marine environment?" and my conclusion is that there's no way something that cheap could be any good. Besides, I absolutely HATE Harbor Freight.

So I'm looking for advice. I've been reading about inverter/chargers. I have an Iota 55 amp charger, four 105 amp hour flooded wet cell batteries, 800 watts of solar ( with another 120 on the way) hooked up to a good MPPT from Outback, an old wind gen, and two new 80 amp Hitachi alternators.

I'm thinking that a 2000 watt inverter/charger would be a good thing. Not sure how much the charger side should be, but I'm guessing something in the 75-100 watt range would be about right.

Am I close? Any suggestions on good quality inverter chargers that will survive the occasional drip of rain when I open the engine room hatch ? Not looking for the gold standard, but just a good, reliable one built for marine use.

colemj · 09-04-2014, 07:26

You don't really get to choose the size of the charger when buying an inverter/charger. Since the charging mode is simply the other side of the inverting mode, the charger rating will be set with that of the inverter.

It sounds like you are all set right now in the charging department. I don't think you will gain anything from an inverter/charger other than redundancy, so you could consider just an inverter if that made more economical sense.

There are not a lot of systems designed to survive actual water ingress. Outback make excellent sealed systems that do. Victron has a drip shield over the top that can help as long as you can mount it in a specific orientation. Magnum is another great unit, but doesn't have much water protection. Other people like Mastervolt, but I have seen many of those fail or not work correctly (particularly the charging mode) - more than I think should be normal. Other than that, fabricating a drip shield is a good idea if you know that water can get to it.

Mark

Saltyhog · 09-04-2014, 07:44

I see lots of great reasons to combine the inverter and charger into one package. Mark mentioned one, that the large power circuitry and magnetics can be shared between the two thus saving weight and cost. In the interests of the other side of the coin, I see two disadvantages however.

1) Shore power voltage limitations. I have not found an inverter/charger with universal voltage input to the charger. This is only a limitation if you plan to cruise to areas with shore power different than what you would normally use. Nice to be able to charge your batteries from shore power and then run the rest of the AC loads from your inverter when in foreign ports.

2) As Mark mentioned, you're putting all your eggs in one basket. If the inverter fails, you likely lose your charger as well. Even if you don't lose both, when having the unit serviced, you are out both the inverter and charger.

01kiwijohn · 09-04-2014, 08:05

I have a 36 foot Cascade with a Xantrex, 2000 watt inverter charger(Used to be known as Hart, now owned by Siemens)
I have had a few problems but they were actually caused by input 120V connections not being well made. The problems was exacerbated by Portland, OR, dealer who didn't know what the hell he was doing! (oyu know the type; "must be the main circuit board, so we'll chuck in a new one, at $350 or so")
Once I SOLDERED the connections, it has worked really well.
I did install a Leviton, whole house surge protector, wiring it into the inlet side, and that has helped with some of those mysterious marina power system.

Canibul · 09-04-2014, 08:07

Some good info, thanks.
I've been thinking of adding an inverter/charger because I've had some issues with the Iota since the lightning strike. It sometimes blows the fuses, and I haven't been able to find an external explanation for that. Intermittent fuse blowing with all boat function unchanged. Sitting at the dock. The Iota also is starting to rust up a bit. I was thinking having an alternate of my own choosing would be pref to having to buy whatever I can find locally if/when the Iota goes to that big heat sink in the sky. That could well be a Chinese motorcycle battery charger.
It's sounding like maybe I should just buy one of each and store the charger away as a spare.

djmarchand · 09-04-2014, 08:29

Yes, there are the <$100 Chinese made inverters and then there are the >$1000 marine inverter/chargers like the Victron, Freedom, etc. For the most part, you get what you pay for.

One inverter/charger that has worked well for me is the Tripp Lite series. Amazon has a 1,250 watt AC, 30 amp DC unit for less than $500. It has run well in a marine environment for more than three years. My Chinese POS lasted less than a year in my garage.

David

01kiwijohn · 09-04-2014, 08:37

Maybe. But; there have been a number of recent marina fires recently, out west and, allegedly, at least one was caused by some type of automotive battery charger.

The Xantrex, and other, marine chargers have a 3 or 4 step charging profile that goes from "Bulk" (ie High Voltage, for a short period) then steps down to "Acceptance" (ie about 13.8 to 14 Volts, medium, for a longer period, to pack the batteries full) then steps down again to "Float" (ie Maintenance mode of about 13.5 to 13.8 Volts) to maintain charge at a level sufficient to reduce battery sulfating, but not boiling the guts out of them( as a constant state type charger may)
With 4 T105 batteries, costing some $600, proper charging is a wise investment. These type of chargers also have an "Equalize" feature( allowing a occasional, sustained period of about 15 V to shed sulfate from the battery plates, keeping them fresh).

Cheechako · 09-04-2014, 09:15

a 1000 watt Heart invertor charger that came with one of my boats seemed to be enough for everything. TV, Vacuum, Small Microwave, drill, sabre saw etc. When it's charging you are connected to the dock, so you dont need a big rapid charge, most the time it's just topping things off. Jst a thought. I dont know what they sell now and if 1000 is much cheaper than 2000.

roetter · 09-04-2014, 17:36

I think I should clarify a few items about charging lead acid batteries.

A 3-stage charger follows the following charge steps.

Stage 1: Bulk charging: This is the stage during which the charger is putting out the rated amps, trying to push the battery to the absorption voltage (usually 14.6V for open LA batteries, less for gel and sometimes AGM, check the manufacturer data). It takes several minutes or a few hours before the voltage has risen to the absorption voltage. This depends on the size of the battery bank and how many amps the charger can provide. The lager the bank the longer it takes. The more amps the charger provides the shorter it takes.

Stage 2: Absorption charging: Now the battery is about 80% full for a properly sized charger. During this stage the charger has finally reached the point at which the battery will not accept more amps than the charger can provide. The voltage has risen to the absorption voltage (for lead acid 14.6V). Now the charger keeps this voltage constant, which means as the batteries get fuller the amps go down. Some chargers use a timer to finish this cycle some measure the amps going in and terminate when the amps has dropped under a certain value. The generally accepted criteria for a 100% charged lead acid is that at 14.6V the amps should drop to under 1.5% of battery bank capacity. So for a 400Ah bank the absorption voltage should be held until the amps have dropped below 6A.

Stage 3: Float charging: The battery is now considered 100% full. Lead acid batteries self discharge over time and should be kept 100% charged when not in use. A voltage of 13.4V is usually specified by the battery manufacturer to maintain the battery at fully charged level. This is the voltage the charger maintains indefinitely.

Here in short form again:
Bulk - Charger outputs full amps. Voltages rises slowly to absorption voltage.
Absorption - Charger maintains absorption voltage. Amps slowly go down.
Float - Charger maintains a lower voltage to prevent battery from self-discharge.

For the picture.
Red is voltage V
Blue is current A

goboatingnow · 09-04-2014, 17:50

Quote:

Originally Posted by Saltyhog

I see lots of great reasons to combine the inverter and charger into one package. Mark mentioned one, that the large power circuitry and magnetics can be shared between the two thus saving weight and cost. In the interests of the other side of the coin, I see two disadvantages however.

1) Shore power voltage limitations. I have not found an inverter/charger with universal voltage input to the charger. This is only a limitation if you plan to cruise to areas with shore power different than what you would normally use. Nice to be able to charge your batteries from shore power and then run the rest of the AC loads from your inverter when in foreign ports.

2) As Mark mentioned, you're putting all your eggs in one basket. If the inverter fails, you likely lose your charger as well. Even if you don't lose both, when having the unit serviced, you are out both the inverter and charger.

I very much doubt the charger and invertor share much circuitry in common at all in the integrated systems. You can do some clever control with integrated systems, but other then some minor circuitry and some shared cabinetry I suspect little is common

Dave

Sent from my iPad using Tapatalk

hellosailor · 09-04-2014, 18:11

canibul-
While I sometimes do buy things at Horror Fright, I only buy them when they are going to be "disposable". When I will be no more than mildly inconvenienced when they fail, or if I'm just buying something for one small job and quality is not job #1.

A HF inverter would frighten me. If it fails, whatever is plugged into it might go up in smoke as a consequence. So, I'd rather spend the $89 in a casino, where I might win, but at least I can't lose anything else.

Inverters seem unreasonably impossible to judge. You can't see what they are unless you open them up. There's no reasonable way to test their performance without buying them all. Reviews are all over the place, with every dog on the internet chiming in. And prices...$400 or $2000 seem to buy the same thing, don't they?

I suppose I'd go for a brand that has a longer warranty without any loud complaints about the equipment or service. There's so many, and ultimately they seem to be all variations on the same Chinese theme, just in different colors. (Color me confused!)

Stu Jackson · 09-04-2014, 18:11

In a recent separate topic about checking a new alternator's output, Maine Sail replied that he's used HFT inverters to provide a load. He said something to the affect that they asre so cheap he can afford to replace a few a year!

That oughta tell you something.

HFT are great for everything EXCEPT anything and everything ELECTRICAL!!!

In 1998, when we bought our boat, I, too struggled with the choices. There is only ONE output from an inverter/charger, but then I figured, "What the heck, that's no different than the single output from the alternator, right?", so I got a Freedom 15 (75A charger, 1500 watt inverter) and added a combiner and moved my alternator output to the house bank. They hadn't yet invented echo chargers or Blue Sea ACRs, but our Yandina combiner has worked flawlessly since then, as has the Freedom.

However, Maine Sail and others have noted that you are essentially "putting all your eggs in one basket" if you get a combined unit. I have a friend in the UK with the same unit and one half of his Freedom failed (I forget which), so he's sol.

Back in 1998, separate units came out price-wise about the same except for more connections. Consider a separate charger sized for your usage, and a separate inverter. Our 1500 does fine ona small microwave and tools, and I've occasionally used it, with the engine running, to get some quick hot water.

Your boat, your choice.

PS - I just can't understand why folks continue to retype "How to charge batteries with 3 stage chargers" over and over again. This should be, by now, basic Electrical 101, and is available on any and all charger and alternator regulator websites and installation manuals. It's nice that they care, but a link to a website with eight paragraphs of material and curves and graphs is all that's necessary to "teach" someone who is new to the game. Welcome to Balmar is a good example.

PPS - Don't bother with Xantrex equipment these days, except for their echo charger.

Good luck.

goboatingnow · 09-04-2014, 18:18

Quote:

Originally Posted by hellosailor

canibul-
While I sometimes do buy things at Horror Fright, I only buy them when they are going to be "disposable". When I will be no more than mildly inconvenienced when they fail, or if I'm just buying something for one small job and quality is not job #1.

A HF inverter would frighten me. If it fails, whatever is plugged into it might go up in smoke as a consequence. So, I'd rather spend the $89 in a casino, where I might win, but at least I can't lose anything else.

Inverters seem unreasonably impossible to judge. You can't see what they are unless you open them up. There's no reasonable way to test their performance without buying them all. Reviews are all over the place, with every dog on the internet chiming in. And prices...$400 or $2000 seem to buy the same thing, don't they?

I suppose I'd go for a brand that has a longer warranty without any loud complaints about the equipment or service. There's so many, and ultimately they seem to be all variations on the same Chinese theme, just in different colors. (Color me confused!)

A good rule of thumb is weight. I currently have a low frequency , Chinese made invertor made for the telecom industry. Massive weight, very reliable low frequency invertor. Can handle huge surge loads. That's the challenge for modern MOSFET driven high frequency invertors, they typically have more protection circuitry to keep the FETS from failing then they have active circuitry.

Dave

Sent from my iPad using Tapatalk

Saltyhog · 09-04-2014, 19:29

Quote:

Originally Posted by goboatingnow

I very much doubt the charger and invertor share much circuitry in common at all in the integrated systems. You can do some clever control with integrated systems, but other then some minor circuitry and some shared cabinetry I suspect little is common

Dave

Sent from my iPad using Tapatalk

I think you would find that many share the magnetics between the two sides. Since the transformer will be one of the most costly components in the unit, it definitely yields some overall cost relief.