Power Inverter Reviews

[Coyote]

Back sorta on topic...

Do you know at all what the output looks like? If you have any access to a sillyscope, it would be interesting to see what the output looks like. Perhaps your machines are reacting badly to ugly wave forms.

[babylonlarry]

Back on topic, I first got a small 800 watt pro sine from west marine and found that it would not run a small microwave. I returned it and got a used Heart Interface 1800 inverter charger. I have had it in service for 10 years with no problems. I leave it on 24/7 for lights. It runs an 8 amp vacuum, but that equates to more than 80 amps at 12 V so I use it sparingly usually with the engine running. I have not run into any devices that did not like the "modified sine" waveform

[Livia]

We bought an inverter from Magnum and had *excellent* customer service from them. It turned out that the newest generation of that type of inverter had a wonky chip in it causing it to function incorrectly. It took them two cross-border fast shipments to rectify the problem but we had a direct line to the person working on it (there are few things more frustrating in that situation than having to call a 1 800 # and speak to a different person each time) and everything was replaced/shipped with no cost to us.

[Yttrill]

"I'm so impressed that Kirk's 800W inverter can handle his washer!" Actually this is not so surprising when you study power usage. Mechanical work is much cheaper than it seems, heating and cooling is very much more expensive. To get some idea think about this: all of the "work" done in a washing machine is mechanical. All those loses come from friction. All loses from friction are equivalent to heating. So now compare: washing your clothes so hard that the water goes up one degree compared to heating the water one degree: both use the same amount of energy.

[tiempo]

Atavist

I think your invertor is fine. The problem I think is the input wiring. You state that it is "just a cigaret jack plug". Chances are that the plug is wired as a 15 amp circuit that may even be shared with additional items. Probably with 14 awg wire or worse. A 400 watt invertor will draw about 33 amps! I think it is choking because of input and not because of the output. I would bet that if you gave the invertor its own circuit with a minimum of 10 awg or larger wire it would not have a problem. As well, a laptop will use less 12 volt power if you use either the manufacturers dc adaptor or a generic 12 volt adaptor.

[redbopeep]

Originally Posted by Yttrill' date='21 May 2010 - 08:02 AM

"I'm so impressed that Kirk's 800W inverter can handle his washer!" Actually this is not so surprising when you study power usage. Mechanical work is much cheaper than it seems, heating and cooling is very much more expensive. To get some idea think about this: all of the "work" done in a washing machine is mechanical. All those loses come from friction. All loses from friction are equivalent to heating. So now compare: washing your clothes so hard that the water goes up one degree compared to heating the water one degree: both use the same amount of energy.

It's the heavy loading (inductive) upon startup that I would expect an 800W inverter couldn't handle. Not the ongoing loading.

[atavist]

Originally Posted by tiempo' date='04 July 2010 - 07:00 PM

Atavist

I think your invertor is fine. The problem I think is the input wiring. You state that it is "just a cigaret jack plug". Chances are that the plug is wired as a 15 amp circuit that may even be shared with additional items. Probably with 14 awg wire or worse. A 400 watt invertor will draw about 33 amps! I think it is choking because of input and not because of the output. I would bet that if you gave the invertor its own circuit with a minimum of 10 awg or larger wire it would not have a problem. As well, a laptop will use less 12 volt power if you use either the manufacturers dc adaptor or a generic 12 volt adaptor.

I'll do as you recommend, see what happens and get back... I just bought a new black and decker 400w inverter but will first rewire the acting up 400w west brand inverter direct to the batteries...

Hopefully that will indeed solve the problem and I can return the new black and decker one.

[edsailing]

Well, I use a Xantrex cigarette socket type inverter input 12v 8 amp, output rated at 60w continuous, 75w for 5 min to run my laptop - no problems whatsoever - best bit is it only cost me £15 or approx $20 US

[Wildernesstech]

This is an old post, but I will throw my 2 cents in as I have a little experience here... We use more than one inverter on our boats: We have a 2000 watt sine wave Xantrex that we love... It has a 100 amp battery charger and is wired with a switch to change between it and shore power for our main supply, with a third position for the generator. BUT, there are often times that we are only watching a movie on the TV, or on one computer surfing the internet and powering the larger Xantrex is not good usage... We then utilize a small 300 watt inverter that is wired with large wiring from the battery bank (through fuses of course) and switched via a high amperage relay coil via the low amperage switching side and a switch on our control panel. Both inverters use GFCI outputs and are wired with tinned wire as ABYC requires. The best part is that the redundancy helps with the worries of unit failure. We have one recepticle in the boat dedicated to the small inverter, which is what we use 90% of the time. We use the larger inverter for using power tools, the microwave, and any other larger draw or starting load. The lower the voltage (i.e. 12 volts), the larger the wiring has to be to avoid voltage losses... Good wiring and bullet proof connections are required in any boats electrical system. Proper grounding is mandatory so that no one in the water nearby becomes electricuted. Voltages that may not stop your heart are still quite dangerous as your muscles may cramp with even small amounts of electrical energy interrupting their electrical impulses and someone in the water may not be able to swim efficiently. Any stray currents add to electrolysis so attention to detail is important. As with any system on a cruising boat, it is imperative to do it right!