Richard,
The system configuration is:
Approx 24.7kW of modules connected to:
2 x 9kW Sunnyboys
1 x 5kW Sunnyboys
Plus
4 x 6kW sunnyislands, with
2 Parallel 48V Strings of (12 x 4V Surrettes ) using 350MCM cable
Wire
The wire is about 1000 feet long 350 MCM in a "twisted" bundle to this
outbuilding
Conditions
The conditions were during the day with full sun, so during the test there is
approx. 47kW of available inverter pointed at only >15 amps (120V) of load(!).
The steady state conditions was a few LED lights, maybe 60 watts worth, plus a
handful of vampire loads, maybe 100-200 watts total. When a pure resistance
load, like a 1000W curling iron was turned on the lights would flicker.
Since the lights flickered from a resistive load, but didn't stay dim, I
assumed it was from a reactive-phase issues due to the transient turn-on -
screwing with the LED dimmer circuits which are already doing a bit of magic to
turn TRIAC waveforms into a DC constant current.
thanks,
Troy Harvey
---------------------
Principal Engineer
Heliocentric
801-453-9434
tahar...@heliocentric.org
On Feb 3, 2014, at 8:33 AM, Richard L Ratico <richard.l.rat...@valley.net>
wrote:
> Hi Troy,
>
> I'm assuming this is off grid. Could you please provide details for the system
> (inverters, batteries, etc.).
> A single, sudden, 20 amp load is not necessarily small relative to the size of
> the system. Is the load 120V or 240 V?
>
> Dick Ratico
> Solarwind Electric
>
>
> --- You wrote:
> On Sun, Feb 2, 2014 at 4:39 PM, Troy Harvey <tahar...@heliocentric.org>wrote:
>
>>
>>
>> We've got a PV system that has long lines from the inverters to the house
>> (1000 ft or so). While the wires are properly sized (2x350MCMs), it
>> inherently has a lot of inductance due to the line-length. What We are
>> noticing is that dimmable LED lights flicker anytime a new load turned on,
>> even if that load is purely resistive and the overall current draw is small
>> (20 amps or so). What I "think" is happening is the LED dimmer circuits get
>> their cue from phase delays, and that the inductance of the line length
>> causes some phase jitter everytime a load is applied - thus causing flicker.
>>
>> Has anyone dealt with this issue successfully (other than switching
>> to incandescent lights)? Would a static capacitor bank at the house do the
>> trick, or do we need some type of active PFC? And if static did you have
>> any issues with constant power draw from the capacitors?
>>
>>
>>
>> Troy Harvey
>> ---------------------
>> Heliocentric
>>
> --- end of quote ---
> _______________________________________________
> List sponsored by Home Power magazine
>
> List Address: RE-wrenches@lists.re-wrenches.org
>
> Change email address & settings:
> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
>
> List-Archive:
> http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
>
> List rules & etiquette:
> www.re-wrenches.org/etiquette.htm
>
> Check out participant bios:
> www.members.re-wrenches.org
>
_______________________________________________
List sponsored by Home Power magazine
List Address: RE-wrenches@lists.re-wrenches.org
Change email address & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
List rules & etiquette:
www.re-wrenches.org/etiquette.htm
Check out participant bios:
www.members.re-wrenches.org
