Humming Invertor

[rhsauto2003]

I just purchased a 93 Bounder and when I plugged it to 110V, the invertor humms quite loudly. Has anyone ran into this problem and hopefully solved it? Thanks for reading

Mark

[RJay]

Are you sure it is an inverter and not a Magnatek converter?

[RV Wizard]

Mark, welcome to iRV2.com. We are glad to have you join us here and we look forward to reading of your adventures and experiences. I am sure you will enjoy the website and forums.
Were the house batteries low on charge before you plugged it in? Do you have a multimeter and know how to use it? If so, check the voltage of the bank when the unit is un-plugged and generator is off; and then again with shore power or generator running; you should see an increase in voltage. If the battery bank was very low, the charger will be working hard to recharge them and louder humming is normal.
If you begin to notice the batteries boiling or getting hot; you may have a bad cell in the bank causing the charger to do what it is. Have the batteries tested if you cannot test them yourself. If bad; replace and recheck the operation of the charger; be it free standing, converter or inverter combination. Let us know what you find. Thank you and good luck.

[rhsauto2003]

Thanks agian, I am new to this but this is a great source. I will check the battery voltages and repost my findings.

Mark

[RJay]

You may want to purchase a battery tester to test the specific gravity of each cell. It's a better indication of the batteries' condition than a voltage test and they are available at most autoparts stores.


The hum you hear is called magnetostriction and is a function of an energized AC transformer. It's normal but annoying. Magnetek converters a particularly subject to this and most people put up with it or replace them.

[wa8yxm]

I too will ask what type of inverter or converter you have.. Any device with a power transformer can do this... And alas, there is no practical cure save replacement and then I'd recommend a different make and or model.

Now.. Other posters seem to think you might have a Magnetek 6300.. If you do I seriously recommend a replacement.. That is a single stage converter/power supply (NOT an inverter) and being a single stage it either never fully charges your storage battery or it overcharges it. .there is no in between.

A good 3-stage such as a Xantrex Prosine (Which is an inverter, and a very good one at that, it's also a 3-stage charger) or a Progressive Dynamics 9200 series.... The batteries will pay for the upgrade.. Believe it or not, by lasting much, much, longer (Assuming the converter does not mess up, which can happen)

[hamguy]

Quote:

Originally Posted by rhsauto2003 I just purchased a 93 Bounder and when I plugged it to 110V, the invertor humms quite loudly. Has anyone ran into this problem and hopefully solved it? Thanks for reading Mark

It is almost certainly a magnatec battery killer. Yank it out and replace it with a PD9260 3-stage convertor. Goto - The 12volt Side of Life (Part 1)
for a great primer on battery maint.

[RVee'r]

You guys crack me up with your comments about the Magnatec 6300. It's neither a battery killer nor is there no "in between". I still have one (do you?) in my old '87 Fleetwood and it works just fine, thank you. Is is a linear model that has been replaced by modern technology? Of course. And I will ultimately replace/upgrade mine in due time, but it's not at the top of my list.

Apparently there's an option known as "Option C". From the original users manual:

Units with Option C contain an automatic, solid-state Battery Charging Section. When 120 VAC power is connected to Power Center, the Charging Section will automatically “sense” the condition of RV battery. If it is below “full charge,” the Charging Section will start charging the battery.

If RV battery has been drawn down quite low, it will be charged at a relatively high amperage rate. If battery has not been severely drained, it will be charged at lower amperage rate. The rate of charge will decline as the battery reaches “full charge”. After battery reaches “full charge”, the Charging Section will drop back to “maintenance” level. It will not resume active charging until battery again falls below “full charge”.

Mine must have this wonderful Option C because my batteries are just fine, after 4-5 years and have not been killed or overcharged yet.

How many had or didn't have this option, I dunno. But it seems these misconceptions about the 6300 series are the RV converter version of "Reefer Madness"

Bob