[RE-wrenches] Magnum Inverters - Digital Clocks Losing Time?

[Allan Sindelar]

Rich, this is a known flaw in the Magnum AE and PAE series. I have one longtime client for whom I supplied a 4448AE around 2009 who later told me that had he known of this frequency issue he wouldn’t have selected Magnum. 
Allan Sindelar 

> On Apr 1, 2019, at 6:56 AM, Christopher Warfel <cwarfel at entech-engineering.com> wrote:
> 
> I would think it has to be frequency. What else could shift the time?  Up until about 2 years ago we were a grid isolated system and no one could use a plug in the wall clock. It takes just a very little off 60 Hz for a clock to keep incorrect time. Being off .5 Hz will result in 42,300 cycles in one day. When I worked in power plants the frequency was a digital display to the 6th place I think. The operator said if that decimal place was off by more than 2 from ISONE, it would trip off line. The steam turbines would be destroyed otherwise. Chris
> 
>> On 4/1/2019 7:08 AM, Rich Nicol wrote:
>> Hello Wrenches
>> I have a site with two PAE 48v Magnum inverters stacked. System voltage fluctuates ~ +/- 4 volts ranging from 243 to 247. Evenly split on the two lines.
>> Site has a few electrical peculiarities I haven’t seen on the many other sites I have with Magnum inverters. Among those is three digital clocks on appliances that lose ~ 5 min per day consistently. A forth clock which is on a weather station with a transformer where it plugs into a receptacle keeps time and of course the computers do as they are web             connected.
>> I checked all neutral connections and verified proper N-G bond.
>> All connections appropriately torqued.
>> My recollection is the modest voltage swings are within Magnum spec. But its constantly moving about which seems somewhat suspect to me.
>> Any suggestions?
>> Thanks
>> RIch
>> 
>> 
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