Inverter squeal

[Dave D.]

Hi all,

We have a small Canadian Tire (yes cheap) 300 watt inverter that works great for around 60 to 90 minutes, then begins to squeal/stop working. Plenty of power (several days) left to run the water pump, use lights, furnace etc. This scenerio occurred in our last trailer as well and with different 12 volt batteries. Typically I'm only using the inverter for a small portable computer. Anyone have any recommendations for another brand of small converter that isn't so fussy about input voltage from the battery or is this a pipe dream?

Thanks,

Dave

[bvansnell]

Dave:

I checked with Canadian Tire's help line for this product, and found this question and answer:
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Problem: The alarm is always coming on. asked 7 months ago by Tula on MotoMaster 300W Mobile Power Outlet and Inverter

Answer:
If the alarm keeps on, that means the battery voltage is below 11V.

At first, we suggest you use this inverter on other vehicle or a fully charged healthy battery. If the alarms still on, please contact with the following support line at 18774668191 for further assistance.
************************************************** **

We had a 200 watt MotoMaster inverter which plugged into a 12 volt outlet in the trailer, but the alarm also came on when I thought the battery had enough power.

I have since replaced it with a GoPower 300 watt true sine wave inverter and have not had any problems. http://www.flickr.com/photos/27335095@N08/8530157914

The purpose of the low voltage alarm is to prevent running down the battery. It would be a good idea to check the line voltage at the 12 volt outlet when you are running the inverter to see if the voltage really is low.

It is possible the culprit is the voltage drop in the supply to your 12 volt outlet. Do you have the same problems if you connect directly to the battery?

[Dave D.]

Thanks for the reply and the information Brian. I'm remiss in not checking the voltage, I'll do it next time. I still think the inverter is the main part of the problem and I would guess that it is no where near 11 volts. What you mentioned about switching to a different inverter and hard wiring it in makes sense to me.

Thanks again,

Dave

[Vermilye]

One point - even if the battery is above 11V, if you have a heavy draw on the inverter & the wiring to it is too small or too long, the voltage drop may give you less than 11V at the inverter input...

[Dave D.]

Jon, the portable computer won't be pulling that much amperage and given the amperage capacity of the battery it should run the inverter for many more hours. I think, given the high cost of what I paid for it when it was on sale (read as very cheap price) I simply got what I paid for. I will check out the voltage drop through the line though and hard wire it in at least to elimate that possibility. If worst comes to worst, I do have an extra set of arc welding cables for wiring around here somewhere

Thanks for your reply,

Dave

[skeena]

"Jon, the portable computer won't be pulling that much amperage"

I had no luck running our laptops off a 300W Motomaster eliminator inverter. The current draw is not consistent and the initial startup would draw more than it could supply. Went to a 700W and the computer runs fine.

[Dave D.]

Mike,

Sorry about the delay, thanks for the reply.

My laptop might be smaller than yours which is why it works great for 60 to 90 minutes and then the squeal. I think a better brand is the solution but as you suggest a higher wattage inverter is likely a good idea as well.

Thanks,

Dave

[gbaglo]

Inverter I had squealed on cold mornings until it warmed up. It was in my company car and plugged in so I heard it every morning when I started the car. Squeal went away when it warmed up. I think it was the fan, if it had a fan. No real clue, but it kept working for a year or two, and then I retired.
So, that's my recommendation. Retire.

[Dave D.]

An update about the inverter squeal. Mike/Skeena had the right answer. We bought a 500 watt inverter (Costco) and over a 3 week period had absolutely no difficulty. The first thing I noticed is that the inverter did not even get warm let alone hot like the old inverter. Lots of computer time .

Dave