Ok guys & girls I have an inverter/charger question. This is in a 2006 Nimbus 340. When I am using my Keruig (Kcup) coffee pot, toward the end of the heating cycle, the Xantrex 3012 Freedom Inverter/Charger will chatter extremely loud (similar to a bad ballast in a fluorescent light). You can feel the inverter/charger case vibrate and the sound can easily be heard inside and outside the coach. This only happens when I use the coffee pot. Nothing else I have tried will do this. Thinking it was the coffee pot I replaced it with a new one. I still have the problem. The circuit I plug into has a 20 amp breaker and a GFCI breaker on it. Neither one has tripped. I have tried other outlets in the coach and the sound still happens. I know this is not normal. When I'm on shore power I use a progressive surge protector at the pole. The voltage is good & there are no error messages. I have been in other parks on shore power with this same problem. The cord runs to a reel and then on to an internal surge guard. The voltage checks ok to and from the surge guard (124/125v). I disconnect from shore power and use the coach generator. The voltage again checks OK. The converter/inverter still does the same thing. I shut off the 12 volt power to the coach and disable the inverter. Using both shore power & gen the inverter/converter still does the same thing.
I then disable the charger on the inverter/charger and again try shore power & gen. The chatter stops.
I am a novice when it comes to electrical and it quickly can exceed my knowledge base. I am leery of opening the inverter/charger case to look at contacts as it is difficult to get at and the unit is still in warranty (installed April 2013).
The Xantrex unit has been set up properly. James T at Foretravel confirmed the settings with me over the phone a while back. I did not asked him about the above problem at that time. Xantrex has not returned my calls as of yet. Does anyone have ideas?
Dick, l recently replaced my inverter with the exact unit you have-Xantrex 3012 Freedom, and a similar thing happened when we attempted to use a counter top oven! But after not using the oven for a few days, when we tried using it again the incident never recurred! So far so good. Waiting to hear what the experts in our group may think! Ed
We have a Xantrex Freedom 3012 that was installed by FOT in July 2014. We have also experienced a strange noise/vibration when using our Keurig K10 mini brewer. We have never been able to determine if it is the Keurig or inverter/charger, but we think it is the coffee maker. It does not happen when we use other appliances.
Larry
Well I talked with an Xantrex Representative this morning. They said this problem shouldn't be occurring. They seemed to be really interested and will get back to me after they check with their engineers. I will keep everyone posted.
Hello Ed long time no see. Hope your doing well.
Dick
Hi there Dick!
Doing great! Will await the rep. report as you say; eager to know the explanation for this rather startling "noice"from our Inverter. Ed
Ok guys I got an email from an Engineer from Schneider Electric / Xantrex today. He asked for info on my coffee pot as they are trying to reproduce the problem. Larry I told him about your KEURIG K-10 mini coffee brewer also. I also sent a video of the converter/charger doing its thing. I'll keep you posted.
Dick
Is the problem when inverting?
The inverter function is disabled and the chatter/vibration continues. When I disable the charger also the problem stops.
Dick,
Thanks for your effort in this matter,
Larry
I'm glad the Xantrex engineers are looking into this "vibration/chatter" three of us are experiencing. Unless others are just not talking about it?!
Ed
Hello Ed. I also told them about your counter top oven. I have sent two videos of the converter/charger singing and vibrating. They replied thanks for the videos as it would give them a good reference when they try things there. After they study the case they will get back to me on what they find.
Yes Dick, thanks for the time and effort you have already put in! It is much appreciated.
Ed
Wonder if the circuit feeding the inverter is not heavy enough, with the inverter charging the batteries. Not sure how this inverter is wired up. On some there are 2 circuits into the inverter and 2 out. If only 1 in that could cause a low voltage condition if charging pretty heavy and a heavy amp load with an oven or coffee maker. Just throwing out some ideas.
That question is above my paygrade. I don't remember if I had this coffee maker before the new Xantrex 3012 was installed. The old Xantrex, If I remember correctly, was a model 2000. I wonder if there is anyone else using one of these coffee makers in their rig, reguardless of what brand of converter/inverter being used, and not having any problems.
We use a Keurig 1 cupper (K-10) all the time. Have a Prosine 2500 and no chatter on shore or inverter power.
I have the Xantrex 3012 in my rig and have not seen any type of issue like this. But I don't have that brand of coffee maker either.
I finally got an answer from the engineers at Xantrex. The email is attached below. I was not able to get the example diagram to attach to this page.
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Hi:
Here's what we found out.
Some loads such as dimmer switches, electric blankets and the Keurig coffee maker use a power control circuit which utilizes a triac controlled pulse width modulation technique. The essence of this technique is one where the load element, (the heater in the coffee maker for example), is powered up for only parts of every AC cycle as shown below,
(I am unable to get the diagram he sent to attach here)
It it this circuit which causes the noise. More particularly it is the fast rising voltage and current which creates high frequency harmonic currents, which in turn make the transformer emit magnetic fields. The noise is transient in nature as it will occur at certain specific pulse widths.
This does not cause any trouble for the inverter, but does make metal in the vicinity vibrate.
Sinewave inverters such as the SW have been around for quite some years now, but the noise issue has not shown up until now, as although electric blankets have the triac PWM they do not use enough power to make noise.
Keurig coffee makers on the other hand have the triac PWM and use a lot of power, so they make the noise.
During our investigation it was pointed out that putting in soft padding at critical locations under the cover and making the case out of a non-magnetic material such as aluminium, will mitigate the noise. That is is the case and so we will be making future product with specific under lid padding and aluminium covers.
Thanks for your help in sending your e-mail videos as they made the investigation a lot easier..
JARMO
We use the Nespresso coffee machine and it does not do that either.
JohnH
I changed to a smaller Keurig (K Cup-K10 mini plus) recently and I still get apx a half a second chatter every now and then. I will give the old Keurig to another family member. I only drink one or two cups a day and I don't need the large Keurig. At least I have it documented in case it turns out to be something later on.