Low Cost Inverters for sale on eBay – a good investment?

My brother-in-law recently purchased a pure sine wave inverter via eBay. In the supplied information the inverter looked like the perfect replacement for his modified sine wave “Xantrex” brand inverter (that has performed flawlessly for a number of years).

The inverter purchased is currently selling (on ebay) for $579 plus $135 shipping

When the inverter arrived, it was immediately clear why it was so expensive to ship from Taiwan … this inverter is very heavy.

Here is the specification section from the eBay listing (as quoted directly from the eBay listing)


  • Output Power Continuous: 1600W
  • Max. Surge Power: 3200W

1. Input Section

  • Input Nominal Voltage:   220Vac
  • Input Voltage Range:  120V~270Vac
  • Line Low Transfer:  120Vac +/- 2%
  • Line Low Return:  130Vac +/- 2%
  • Line High Transfer:   270Vac +/- 2%
  • Line High Return:   260Vac +/- 2%
  • Input Frequency: Auto 50Hz/60Hz (45Hz~75Hz)

2. Output Section

  • Output Voltage:  220Vac / 230Vac / 240Vac re-settable via LCD panel
  • Waveform: Pure Sine Wave
  • Voltage Regulation (Batt. Mode): < 3% RMS for entire battery voltage range
  • Output Frequency: ADJ. 50Hz or 60Hz +/- 0.1Hz
  • Total Harmonic Distortion Output THD: < 3%
  • Maximum Load: Up to short circuit
  • Asymmetrical Load Max.: Up to nominal output power
  • Overload and Short Circuit Protection: Automatic disconnection
  • Overheating Temperature Protection: Acoustic warning before shut-off. Automatic restart
  • Power Factor: 0.8
  • LCD Display: UPS status, I/P&O/P Voltage Frequency, Load %, Battery Voltage & %, Temperature, Model
  • LED Display: Normal (Green), Warning (Yellow), Fault (Red)
  • Maximum Efficiency: 85~92%

3. Battery Section

  • Voltage Range: 24VDC (20~32VDC)
  • Backup Time (at full load): Long time available
  • Input Frequency Range: 45~70Hz
  • Max. Charging Current (5 steps selectable): > 50Amp

4. Audible Alarm

  • Battery Mode: Beeping every 4 seconds
  • Low Battery: Beeping every second
  • Solar Inverter Fault: Beeping continuously
  • Overload: Beeping twice per second

5. General date

  • AC By Pass Time (UPS Mode): <10ms max
  • Operation Temperature: -20C to +55C
  • Max Current at Transfer Relay: 40A / AC 220V
  • Audible Noise: Less than 55dBA (at 1M)
  • Relative Humidity: 0-95% non-condensing


  • LCD display
  • Microprocessor based design
  • Heat-Sink built in internal
  • Soft Start
  • Input & Output isolated
  • Auto temperature control fan
  • Reverse polarity protection. / by fuse / diodes /Output short circuit protection
  • Temperature protection
  • Overload protection
  • Input low voltage protection
  • Input high voltage protection
  • Low battery alarm
  • Low battery shut-down

Fitting and testing the inverter…

The inverter was simple to fit and apart from the weight, not difficult to mount.

The first test (after rechecking all connections) was to start the inverter. This is not as simple as you would think … it involves holding down two buttons, releasing them, then at the right moment pressing them again. If you fail to get this right, the inverter immediately shuts down again.


The output from the inverter was great – it was indeed a pure sine wave. The voltage regulation was fine and everything was looking great. The next test was to load the inverter – the motorhome microwave would do that nicely (it is a 1000w output microwave with an input requirement of 1300watts). More good news, the inverter was quite happy to heat a glass of cold water in the microwave.  Next test … the charger.

For this test we attached my Honda 2.0i inverter generator. The reason for this was twofold… firstly to make sure that the inverter was happy to accept input from the Honda generator and secondly to make sure that the 50amp charger built into the inverter would not overload the generator.

The inverter had no issues with the AC from the Honda generator and after a few seconds, switched over to “pass through” mode and started charging the batteries. We were a little surprised that the generator did not groan at all. Our ammeter quick told us why … the charger was only charging at 7 amps. At this point we assumed that the reason for this was simply that the batteries were near fully charged. We decided to allow the battery bank to discharge over night and repeat the test in the morning.

The following morning the motorhome PL20 solar controller reported that the batteries were at 75% of capacity. We repeated the charging test fully expecting to see 50amps of charge flowing into the batteries … 7amps still! At this point I became a little worried. We then discharged the batteries a little further by heating another glass of water in the microwave – well that was the idea. The inverter stopped, displaying only the word “ERROR” after about a minute of powering the microwave.

We then decided to discharge the batteries even further (using the motorhome fridge) and try again the following day.

The next morning we found that the Waeco fridge had disconnected itself due to low battery voltage and the PL20 reported a battery capacity at an extremely low 55%. This is far lower than I would recommend anybody discharge lead acid batteries.

The charge test was repeated using both the Honda generator and mains power. No matter what we did, we could not get more than 7 amps out of the inverter charger.

Time to write to Taiwan Motors …

It seems that Taiwan motors has a much more active sales team than their support team. Days passed without an answer.  When an answer finally came, it was simply “please wait”.

To cut a long story short, after numerous emails back and forward between us, we have no satisfactory answers.

The two major outstanding issues with the inverter are :

Despite the specifications stating very clearly that the charger will charge at 50amps, we have been unable to get it to produce more than 7amps.

The inverter will not run a heavy load (1300w) for more than about 2 minutes before shutting down.

Here is a selection of emails from the “technical support” at Taiwan Motors…

How are you? Very sorry for our late reply.

1. The max charging current is 50Amp,but this is not continuous charge current. Moreover,the max charge current 50Amp will be only achieved in the condition of the battery is out of electricity and also depends on the distance of DC battery cable between battery and inverter.

2. Please kindly discharge the battery till 10% and charge the batteries and try to use inverter with battery charger to charge battery again. Please use a multi-meter to measure the charging current and take some picture of the multi-meter display for our reference.

Now I am sure that anybody that knows even the slightest bit about lead acid batteries knows that to discharge below about 50% severely affects the life of the batteries. To even attempt to discharge to 10% is to kill the batteries.

Taiwan Motors finally agreed to allow us to return the inverter for servicing with freight being our responsibility (and to be fair, this was stated in the original listing). Australia Post quotes in excess of $300 to post the unit back to Taiwan.

Conclusion – This has been a hard lesson, after over $800 of investment we are left with a dilemma … should the unit be returned for service (with the very real possibility that the issue is a design fault and thus not resolvable) or cut our losses and use the inverter as a chock?

I hope that this article may serve as a warning for others who might find that the low cost of these inverter/chargers makes them an attractive option for a motorhome.

Tags: , , , , , ,


Has the information on this site been useful?

If it has, please consider using the donate button at the bottom of our home page. All donations are used to maintain and improve the website and we are very grateful for any support.


Building or Upgrading a Caravan or Motorhome?
Take advantage of experanced, expert electrical advice.

We happly answer question every day about the articles on the website - and we will always do this at no cost.
But if you are building, rewiring or adding solar panels to your motorhome or caravan and want to get it right the first time, read about our paid consultancy service.

click here for more information.

10 Responses to “Low Cost Inverters for sale on eBay – a good investment?”

  1. David Says:


    Give them a negative ebay rating and see what happens.
    I had a issue with an ebay supplier recently and did that and they were all over it like a house on fire as if they get too many they get suspended from trading.

    Hopefully, it works out for you but it sounds like a design fault, doesn’t it?

    Thanks for reporting.

    Best Regards

  2. Hobo Says:

    Sadly, due to some medical issues, the inverter sat in its box for 8 weeks before being tested. This meant we did not have the opportunity to provide negative feedback.
    As far as I can see – the only two possibilities are…
    1. It is simply a faulty unit (I feel that this is unlikely as it has two seemingly unrelated issues)
    2. It has a design fault

    Either way, we are not prepared to spend the money sending it back to the supplier to find out.

    (BTW – this inverter was not purchased for our own use – but it was purchased on my recommendation after reading the specifications – imagine how I feel about that!)


  3. john Says:

    heres the latest reply from the company ragrding my inverter

    I don’t believe anybody told you warranty IS void, you’ve probably been told IT might be voided if the inverter was overloaded.
    The peak power of a 600W vacuum cleaner is much bigger than 2500W – you can check that with the vacuum manufacturer if you like. It’s also clearly stated in the inverter manual that for products that have electric motors you must multiply the power by 7 – this comes from the manufacturer and is not something we made up.!!
    So, 600W X 7 is 4200W which is much bigger than the inverter capabilities.
    Of course this can be easily checked – we can test the inverter and see what happened – if it is a manufacturer fault and it’s still in warranty then we will fix it. If it was overloaded then you must cover the repair costs.

    – bit_deals

    cheers john

  4. Hobo Says:

    Interesting John – clearly these guys have NO electrical knowledge at all. The reason that inverters have “surge rating” that is normally double the continuous rating, is to allow them to start motors etc. We have a 1500w inverter and we run our 1400w vacuum cleaner from it all the time. So if your 600w vacuum cleaner damaged a 2500w inverter I would be very worried about the quality of the inverter.
    If your 600w cleaner did manage to draw 4200w (which BTW is still less than the 5000w surge rating of the inverter) it would overload ANY household socket. 4200w @ 240v = 17.5amps – far too much for a standard 10 amp socket.
    I suggest you write to the manufacturers of the cleaner and ask them if it really does draw 4200w when it is running …. not a chance!

  5. john Says:

    i will keep you informed
    waiting there reply

    cheers john

  6. john Says:

    I don’t think the discussion here is about my qualifications
    A power inverter is a little more complicated than you think. When you plug the vacuum unit in the house power outlet you have AC current but on the inverter the draw from the battery is DC current and because is very low, around 20A, it needs a bigger capacity to be able to cover the start-up powers.
    So the inverter needs to be bigger not to give you more Amps but to be able to create faster the start-up power required by induction motors.

    Anyway, we can discuss this back and forth for days.I told you – we can check the inverter – if it’s a manufacturer fault it will be fixed or replaced.
    And when you got the product you should have read the manual and if you didn’t agree with the manufacturer regarding the loads you should have return the item.
    Manufacturer says you cannot run a 600W motor on this inverter – the point is not if they are right or wrong, it’s their product so they probably know better.
    Inverters capable to run big electric motors are called professional inverters with 10s start-up power coverage and are much more expensive, not to mention they are around 40kg

    So, if you want this checked, just send it back to the address on invoice and we’ll check it

    well gav theres there reply

    total waste of time

    im going to relist this unit on ebay( free to good home..dead )

    have told them so
    is good advertisment for there company!!!!!!!!!!!!!!

    eeven if it costs me $10

  7. john Says:

    Continuous power: 2500W
    Peak power: 5000W
    Input voltage: 12V DC
    Output voltage and frequency: 240V AC, 50Hz
    Output wave: modified sine wave
    Efficiency: > 90%
    Static current: < 1.5 A
    Low input voltage warm: (10.5+/-0.5)/( 20.5+/-0.5)V
    Low input voltage protection: (10+/-0.5)/(20+/-0.5)V
    Output overloads protection: 5000W
    Overloading protection
    Low input voltage alarm and protection
    Short circuit protection
    Over temperature protection
    Size: 400 X 200 X 75 mm
    Suitable for AU socket style

    thers the specs for there inverter

    i hope it helps other s here
    and hope they read this

    cheers john

  8. Ray Says:

    I also looked at inverters on Ebay and while the price was attractive I was concerned about quality and reliabability. In the end I chose an Australian made Latronics pure sine wave inverter.

  9. Hobo Says:

    A very wise move. There are way too many horror stories relating to cheap inverters.

  10. Graeme Says:

    I too purchased a pure sine 2500 watt inverter from bit deals on ebay. the inverter performed as expected the first time I used it, it was installed on a houseboat to primarily run an evaporative cooler needing 500 watts.
    The second time it was used it simply stopped working and smelled. I contacted the supplier and the replies you have above closely mirror the responses I received.
    I too was too late to post a negative feedback.
    I have since purchased a projecta inverter from another supplier and the new unit performs as expected.
    I also purchased 4 solar panels which w=are supposed to give 480 watts. While not expecting to receive 480 watts I expected more than around 50%, but I can live with that.

Leave a Reply

You must be logged in to post a comment.