Inverter Pros/Cons

[o1marc]

Electrical is not my forte, so I will dive heavily into this forum shortly. I saw this at HF the other day and was wondering the pros and cons of this one. Also thoughts on units that are better or cheaper or worth the extra money, etc.

[Iceni John]

I would not buy any high-current electrical item from Harbor Freight! My general rule for anything Made In China is to derate by 50%, i.e if you want a 1000W inverter buy one rated for twice that power. It will draw more standby power, but the FETs should last longer. I also use that same rule of thumb for Chinese bottle jacks, so I buy 20-ton jacks for 10-ton loads, etc etc.

John

[brokedown]

I don't know what all you plan to run from it but I've had great luck with my Bestek 1000W. They also have a 2000W if you need more, and it's cheaper than the 2000W HF unit: https://amzn.to/2LOr5D3

If you're planning to run an air conditioner from it you probably want to spend the extra on a pure sine wave unit. If not, I've used mine to run my chest freezer, various power tools, my TV, and a bunch of other crap without any problems.

[o1marc]

Originally Posted by brokedown

I don't know what all you plan to run from it but I've had great luck with my Bestek 1000W. They also have a 2000W if you need more, and it's cheaper than the 2000W HF unit: https://amzn.to/2LOr5D3

If you're planning to run an air conditioner from it you probably want to spend the extra on a pure sine wave unit. If not, I've used mine to run my chest freezer, various power tools, my TV, and a bunch of other crap without any problems.

Ultimately I'd like to be able to power anything off grid, so more is better. Are you referring to something like this? $30 cheaper than the HF one at half the wattage.

https://www.amazon.com/BESTEK-2000W-...d=AWZ3LXPHZK09

[brokedown]

I believe this is the one you saw at HF: https://www.harborfreight.com/2000-w...ter-63429.html

They're both 2000W continuous, the Bestek claims a slightly higher "peak" than the HF unit. The peak figure is just buffer room for devices that have a heavy burst at start. When you pull the trigger on a circular saw it's gonna very briefly take twice as much power as it takes cutting through wood just to get spun up. The continuous figure is what it is able to deliver for more than a second or two at a time.

If you're looking at a pure sine wave unit those tend to cost about double so I don't normally suggest them unless you know you need one. AC units tend to have short lifespans with modified sine wave inverters, which is why I call them out specifically. It will work on a modified sine wave unit, it will draw a bit more power than if it was on a pure sine wave unit, and it will have a shortened lifespan. But most everything else won't care.

[Thomas810]

I work from home and I use my bus sometimes as an outdoor office and take it to parks for a change of scenery during the workday... I recently got this inverter to power my office stuff - seemed like a really good price... I doubt the claim of the pure sine wave but I run the bus engine for AC when it gets hot and just need to power a couple of laptops and whatnot... https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

[o1marc]

Besteks are also made in China. Seems like a better unit for less money so I would opt for it over the other. The Bestek doesn't say in the details whether it is sine or pure sine, which I don't understand the difference yet.

[brokedown]

Doesn't mean a lot when you're running from alternator power, but if you were on solar it's really wasteful to charge a laptop from an inverter. You're taking DC power from batter and converting to AC in the inverter, than back to DC in the charger brick. You'd save a lot of power skipping those conversions and just boosting you voltage.

I use this for mine, it's a "one size fits most" unit: https://amzn.to/2NNPWYm

[brokedown]

Bestek is from china for sure. I'm comfortable recommending it because I've been using mine for almost 2 years.

If it doesn't explicitly say pure sine wave, it's modified.



The power in your house is a pure sine wave. Technically, it's better. From a practical standpoint, it rarely matters.

[Thomas810]

Agreed DC -> AC -> DC is wasteful... but simpler to wire the bus for running on AC - also when using the engine for source not much reason to spend the extra for DC connections - I run multiple computers, router, hot spots, lights, etc when I use it as an office and when camping kids run phone chargers, computers, etc - easier to have known common connections for kids and friends rather than try to get them to agree on charging solution they are not use to...

[Dapplecreek]

I just wired in that HF 2000W inverter, and it seems to be doing a fine job. Used it for an angle grinder the other day for the last few seat bolts.

I wired a deep cycle battery to the starting batteries, via a cutout switch. Then I ran wires to the inverter through a 250A fuse. If I did it right, I can charge my deep cycle battery and run my freezer while the engine is running, and then (witht he cutout switch) keep from running my starting batteries down overnight as I run a fan from the inverter.

Bench-testing it, I was able to run the freezer and a small portable air conditioner at the same time. The freezer could start when the ac was on, but the ac tripped the breaker on the inverter if it tried to start while the freezer was on. I was amazed, frankly, that I could do both.

[Thomas810]

Originally Posted by Dapplecreek

I just wired in that HF 2000W inverter, and it seems to be doing a fine job. Used it for an angle grinder the other day for the last few seat bolts.

I wired a deep cycle battery to the starting batteries, via a cutout switch. Then I ran wires to the inverter through a 250A fuse. If I did it right, I can charge my deep cycle battery and run my freezer while the engine is running, and then (witht he cutout switch) keep from running my starting batteries down overnight as I run a fan from the inverter.

Bench-testing it, I was able to run the freezer and a small portable air conditioner at the same time. The freezer could start when the ac was on, but the ac tripped the breaker on the inverter if it tried to start while the freezer was on. I was amazed, frankly, that I could do both.

I would love more detail on what you did... cut out switch and all with the batteries... that sounds like exactly what I might want to do to save from always running the engine when I do stuff in the Bus... I actually purchased an 800 watt AC unit for the bus and wanted to start using it but was scared to run down the bus batteries if I used it... is there some reference that you know about to wire like you described? I have two batteries in the bus - but they are for cold cranking the engine... not deep batteries... its not clear to me how you connected in the third battery... It sounds like you used something like this... https://www.powerstream.com/battery-isolator.htm

[JDOnTheGo]

o1marc,

In very general terms, induction type type motors/devices won't run as well from MSW power (less efficiently, more heat). That said, most of them do work. I ran my coach (w/residential refrigerator/freezer) for a number of months with a MSW inverter. The refrigerator did not "sound" happy. The fan and compressor were not "right" (hard to explain) when running from the inverter. I switched to PSW and now there is no difference in "sound" when running on inverter vs shore power. I don't know that MSW was going to shorten the fridges life but it sure didn't sound like it was extending it. Microwaves never seem to work as well on MSW either (cup of coffee requires more time to heat up, for example).

[Dapplecreek]

Originally Posted by Thomas810

I would love more detail on what you did... It sounds like you used something like this... https://www.powerstream.com/battery-isolator.htm

You're on the right track. I didn't have the dough or the time to wait for one of those, so I did a knife switch instead. That relay is what I *wanted* - automatic set-and-forget. As I prepare for the evening I'll have to climb out of the bus, open the battery box, disconnect the battery, close the box, and get back in the bus.

• Red wire from alt/starter to StartBat1 pos and then to StartBat2 pos (stock)
• HF 3' 4/0 red wire from StartBat1 pos to deep cycle battery pos
• 250A fuse bolted to positive terminal on deep cycle battery
• HF 6' #2 red wire bolted (nut and bolt) to other end of fuse
• HF 6' #2 red wire then goes into loom, through floor, and to inverter

• Black wire from alt/starter to StartBat1 neg then to StartBat2 neg (stock)
• HF 3' 4/0 black wire from StartBat1 pos to end of knife switch that has bolt
• Ring end of knife switch arm bolted to deep cycle battery neg terminal
• HF 6' #2 black wire from deep cycle neg into loom, through floor, and to inverter

Will add photos later today.

• Inverter is mounted just back from driver's seat, on outside wall.
• Loom is that corrugated stuff (looks like a trachea, if you've ever gutted a deer) with a slice in it. Used commonly in automotive stuff; it's what the bus uses.
• Hole in floor made with a 1 1/4" Diablo hole saw. Can't say enough good stuff about Diablo hole saws - expensive, but they cut through the steel like butter. The Harbor Freight hole saw just ground down. (Note: first trouble I've ever had with HF stuff). I sanded the edge of the hole before adding the wire/loom.
• Wires (in loom) routed down through hole, around a corner, and into the existing hole in the back of the battery box.
• Deep cycle battery mounted next to the two starting batteries (there was room an extra battery by scooting the two starting batteries toward the rear).

[david.dgeorge07]

Consider adding a voltage sensitive relay in addition to your manual cut out switch between your starting batteries and your house batteries. Makes it very slick.

[Dapplecreek]

Originally Posted by david.dgeorge07

Consider adding a voltage sensitive relay in addition to your manual cut out switch between your starting batteries and your house batteries. Makes it very slick.

?

So if the whole bank drops below X volts, it pops open and avoids pulling down the starting batteries any further?

If so, what is the magic voltage?

[david.dgeorge07]

Originally Posted by Dapplecreek

?



So if the whole bank drops below X volts, it pops open and avoids pulling down the starting batteries any further?



If so, what is the magic voltage?

https://www.amazon.com/Smart-Battery...cbL&ref=plSrch

12.9 V off 13.4 V on.

[o1marc]

After looking at the Bestek 2000w for $139 on sale, today I get this from Amazon. 3000w for the same price. I noticed mixed reviews, but it seems the ones that work, work well.
Thoughts?
https://www.amazon.com/gp/product/B0...760_em_1p_5_im

[PNW_Steve]

Originally Posted by o1marc

After looking at the Bestek 2000w for $139 on sale, today I get this from Amazon. 3000w for the same price. I noticed mixed reviews, but it seems the ones that work, work well.
Thoughts?
https://www.amazon.com/gp/product/B0...760_em_1p_5_im

I didn't see any mention of what you are using for your house battery bank. What are your plans for feeding that inverter?

[o1marc]

Originally Posted by PNW_Steve

I didn't see any mention of what you are using for your house battery bank. What are your plans for feeding that inverter?

Haven'y gotten that far yet. Will have enough battery to run that converter if that's whats need to supply my fixtures.