[RE-wrenches] 1/2 wave loads

[Kent]

Kirk,

Unless I remember incorrectly, a single diode gives half wave 
rectification, full wave rectification requires two diodes with a 
center-tapped transformer or a bridge rectifier. Half wave rectification 
injects a dc current on the inverter output; that is why some inverters 
don't do well with it.

Kent Osterberg
Blue Mountain Solar


On 1/30/2025 5:59 PM, Kirk Herander via RE-wrenches wrote:
> Fortress tells me they just released the latest firmware to deal with 
> half-wave loads. This version was put out for download a few days ago.
>
> In my case, they say it "might" help (CFL to) LED retrofit lamps from 
> flickering when switching grid pass-thru to inverter AC. I am dubious. 
> but I've since read that some LED lamps do not employ full 
> rectification, just a single diode.
>
> On Thu, Dec 19, 2024 at 8:54 AM Jay via RE-wrenches 
> <re-wrenches at lists.re-wrenches.org> wrote:
>
>     Hi Howie
>
>     That’s great info thanks.
>
>     They never mentioned that to me.
>     And I’ve not heard about an actual
>     Hardware issue/fix.
>
>     The latest firmware 1E1E is supposed to “fix” it. It also requires
>     a separate firmware update for the display which you have to do in
>     person, stupid.
>
>     Jay
>
>
>
>>     On Dec 18, 2024, at 9:05 PM, Howie Michaelson via RE-wrenches
>>     <re-wrenches at lists.re-wrenches.org> wrote:
>>
>>     
>>     I installed a couple of EG4 18k inverters off grid this past
>>     spring, made by LuxPower as is the Envy.  They look very similar
>>     both visually and programmatically. Withone install, there has
>>     been a steady problem of the inverter shutting off when the
>>     client uses a hair dryer. The other client has not reported any
>>     issues with the inverter cycling off.  Tech Support's solution to
>>     this issue which they referred to as stemming from half-wave
>>     loads, was to run another load simultaneously which was supposed
>>     to help prevent the nuisance momentary shutdown, but according to
>>     the client, it hasn't helped. After bugging tech support for
>>     several months about this issue, they finally told me that there
>>     was a hardware design flaw that they were working on resolving
>>     and when they had it fixed, they would send out a replacement
>>     inverter. I asked if they would be replacing both inverters, but
>>     they said since one hasn't reported any issues, they would not be
>>     replacing that one. That was at least 2 months ago, and I have
>>     not heard anything since.
>>
>>     Howie Michaelson
>>
>>
>>     On Wed, Dec 18, 2024 at 4:02 PM Jay via RE-wrenches
>>     <re-wrenches at lists.re-wrenches.org> wrote:
>>
>>         I will add that I’ve heard privately off list that it’s
>>         actually smaller loads that seem to be the issue.
>>
>>         And larger 1500 watt electric heaters seem to work ok.
>>
>>         I’m wondering if anyone else has come across this issue and I
>>         guess more importantly is there a fix?
>>
>>         Jay
>>
>>>         On Dec 18, 2024, at 1:52 PM, Jay <jay.peltz at gmail.com> wrote:
>>>
>>>         
>>>         Here is what I understand 1/2 wave loads to be.
>>>
>>>         As I understand it, Heater loads are the main issue.
>>>
>>>         Toasters, toaster ovens, hair dryers, aquarium/terraium
>>>         heaters etc.
>>>
>>>         But if there are other things pls let us know
>>>
>>>         Jay
>>>
>>>>         On Dec 18, 2024, at 1:34 PM, GLBCC via RE-wrenches
>>>>         <re-wrenches at lists.re-wrenches.org> wrote:
>>>>
>>>>         
>>>>         What is a half wave load?
>>>>
>>>>         On Dec 18, 2024 13:35, Jay via RE-wrenches
>>>>         <re-wrenches at lists.re-wrenches.org> wrote:
>>>>
>>>>             Hi all.
>>>>
>>>>             I’ve recently been made aware that the fortress
>>>>             inverter isn’t too happy with 1/2 wave loads.
>>>>
>>>>             I’m wondering if this is an issue with the AIO or solark?
>>>>
>>>>             Thanks in advance
>>>>
>>>>             Jay
>>>>
>
>
> -- 
>
> *Kirk Herander / **kirkh at vermont.solar*
>
> *Owner|Principal, VT Solar, LLC*
>
> */Celebrating our 34^st  Anniversary 1991-2025!!/*
>
> dba Vermont Solar Engineering
>
> 802.559.1225
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20250131/e07ae44f/attachment.htm>