On 5/22/2014 4:54 AM, DerbyDad03 wrote:
I bought this inverter at you-know-where. I will be calling the tech
support number given in the manual, but I thought I'd run my questions by
you folks also.

http://t.harborfreight.com/1000-watt...oogle.co m%2F

1 -When I power it on, the fan starts, runs for about a second and then
stops. Is this normal? Will the fan start again if required?

2 - When I plug in a lamp with a 72W bulb, it works fine. When I plug in a
air mattress pump (120V, 1.0A) the pump may or may not start and the
inverter chirps its alarm. Sometimes the pump seems to run fine, other
times, not so much. The chirping is more evident and consistent when the
pump is running at what appears to be full speed.

Shouldn't even a cheap 1000W inverter be able to handle the pump without
breaking a sweat?

(I'd return it and try another inverter, but both of my local stores are
out of stock right now.)

You could try another one, but it sounds like HF just rated the inverter
way too high. Or else you're not using sufficiently thick gauge wire.
The motor may be drawing more current when using a modified sine wave
that the inverter puts out. Allowing for losses in the conversion you
should use about 10AWG wire and connect directly to the battery. For
higher loads look at 4AWG wire, i.e.
http://www.amazon.com/dp/B007L6DYVS or 2AWG i.e.
http://www.harborfreight.com/automotive-motorcycle/power-inverters/300amp-6ft-inverter-cable-set-69537.html.

You may need the proper gauge wire even when you're operating the
inverter with a load that is far lower than it's capacity.

"Use an inverter" is often a stock answer in forums regarding running
120V devices off of 12V, but it's rarely a good answer. For laptops, an
Auto/Air adapter, essentially a DC-DC converter is a much better option.
For things like compressors, there are plenty of them with 12VDC motors.
And of course there are plenty of 12V light bulbs, i.e.
http://www.campingworld.com/shopping/item/15-watt-fluorescent-12-volt-bulb/44377.