[RE-wrenches] Outback wave form

[boB]

I believe these problems are mainly due to the high frequency switching 
content of the typical sinewave inverter
these days.

I (and other manufacturers I'm sure)  would be very interested to know 
which appliances are susceptible to
this  noise so that we can try to reduce these incompatibilities.    I'm 
sure we can't take care of 100% of
the incompatibilities but we can try to get closer.

For instance, what kind of coffee maker was that, Jeremy ?

boB



On 4/16/2013 11:36 AM, Bruce Erickson wrote:
> I'm having a similar issue with a GRID-TIE inverter just now. SMA 5000US which, when it wakes up every morning, removes the date and time from the programming in the customers' Monitor brand kerosene heater. They have to re-enter it daily, which is annoying enough, but when they go out of town, they have to leave the inverter off to avoid coming home to a cold house.
>
> So far SMA has had us move the breaker as far as possible from the heater breaker, to no avail. They had no other suggestions. I used a Panamax plug-in power conditioner with 50 dB of EMI filtering on the heater outlet, which has reduced the frequency of the problem to once a day, when it wakes up, from a few times a day. Trying a different heater is out of the question due to cost, so I'm stumped as how to avoid an unhappy customer, unless the answer is experimenting with more robust power conditioners.
>
> Bruce Erickson
> Mendocino Solar Service
> PO Box 1252
> Mendocino, CA 95460
> 707-937-1701
> 707-937-1741 fax
> bruce at mendocinosolar.com
>
>
>
>
> On Apr 16, 2013, at 11:12 AM, Dave Palumbo wrote:
>
>> Jeremy,
>>
>> << What to look for? >>
>>
>> Unfortunately, probably a different coffee maker.
>> I've gone through this with several different appliances over the years on
>> sine wave inverter output. Washing machines, refrigerators, dishwashers it
>> could be anything with electronics. Specific manufacturers typically cannot
>> be avoided in order to solve this issue. Year to year manufacturers may
>> change the design of their appliances, so blanket statements on what works
>> and what doesn't are unreliable. All appliances (excepting a few) are
>> designed to operate on utility power, not inverter power. Inverter power
>> (excepting Exeltech and possibly others) typically has more distortion than
>> utility power. Some appliances cannot tolerate the simulated inverter sine
>> wave power. I always council my inverter customers that I cannot guarantee
>> that all appliances with work flawlessly and that some may not work at all.
>> I advise off-grid clients to buy appliances where there is a liberal return
>> policy.
>>
>> David Palumbo
>> Independent Power LLC
>> 462 Solar Way Drive
>> Hyde Park, VT 05655
>> www.independentpowerllc.com
>> Vermont Solar Partner
>> 25 Years Experience, (802) 888-7194
>>
>>
>>
>>
>> -----Original Message-----
>> From: re-wrenches-bounces at lists.re-wrenches.org
>> [mailto:re-wrenches-bounces at lists.re-wrenches.org] On Behalf Of All Solar
>> Sent: Tuesday, April 16, 2013 12:47 PM
>> To: re-wrenches at lists.re-wrenches.org
>> Subject: [RE-wrenches] Outback wave form
>>
>> Have a client with a new coffee maker that will not run from their new dual
>> outback setup. Has anyone heard of this lately. We have had no problems with
>> appliances and sine wave inverters. What to look for?
>>