Charging issue

I was referring to the original question about "hybrid power sharing", which works by a set current limit, thus the "overcurrent reaction" being slow.

FETs are being switched at a cycle time of ~42uS (0.042mS), with a variable pulse width minimum well under 1/500th of that, or 83nS (0.000083mS).  There's no lack of control ability, just a reaction requirement.

For FET amperage overload on the C board, reaction time is not limited by the CPU speed, as it is handled in hardware (not software). 

For system overload / AC backfeed (admittedly the latter being the most dangerous; I'm aware of at least 2 inverters being damaged by connecting their outputs directly to a "hot" AC panel), technically the CPU can see amperage readings (and polarity) approximately every 4uS (0.004mS).  The challenge becomes whether or not to take action based on a single sample.  If the code is too trigger-happy, it'll cause errors/shutdowns based on "dirty" or surge loads.  But if it takes too long to react, it won't be able to quit the FETs in time to prevent damage.  There may not be a happy medium here, unfortunately.

I believe it’s better to sell the inverters as off grid only. AC should only be used for pass through or charging or both. Having an inverter that can back-feed or grid-tie can be dangerous if not properly installed. 

For system overload / AC backfeed (admittedly the latter being the most dangerous; I'm aware of at least 2 inverters being damaged by connecting their outputs directly to a "hot" AC panel), technically the CPU can see amperage readings (and polarity) approximately every 4uS (0.004mS).  The challenge becomes whether or not to take action based on a single sample.  If the code is too trigger-happy, it'll cause errors/shutdowns based on "dirty" or surge loads.  But if it takes too long to react, it won't be able to quit the FETs in time to prevent damage.  There may not be a happy medium here, unfortunately.

The  powerjack  rev 10.3 control board take too long to react  and blow the FETs .   The  rev 11.1  control board is too trigger happy  and I can not  get to max load  as I try many times  and   the inveter will shut down first .   I  have not try  to backfeed  grid  power to the  output of the inverter yet to see  if the  rev 11.1  control board will shut down and save itself  .   Maybe  one  day  I wiil  try and see if it will shut down  if grid power backfeed  with the inverter ON .   If not shut down in time then   all the  FETs will be no fire  and the  trace in the mainboard  will be shorted and crack  and the  LF driver  and control board will be  gone .   Powerjack  will make more money selling another  inverter  .   

I guarantee you that it will blow up.  0% chance of survival.

Why?

PJ inverters can't determine the direction of power flow. 

They also don't have an instantaneous overload trip built in.

I do agree.  Maybe I'm too much of an "off-gridder", but I don't like connecting AC mains to any important equipment.  There's some serious red tape for backfeeding into the power grid without the proper permits--these days with smart power pole meters, you're likely to get caught redhanded within seconds.  While it will be completely and totally possible on the Rev. C GS inverters to run backfeed/grid-tie functions, I don't have any immediate plans for exposing said functionality...simply because of the legal ramifications.

However, the "parallel" function itself by definition of current implementation in GS inverters, is a "frequency throttled grid-tie inverter."  This functionality will be integrated deeply into the upcoming Rev. C functionality--simply because so much can be done with it (including absolutely seamless return transitions from grid to battery.)

I still think that a split-sync is much better than 2 inverters in parallel. Either split-sync or three phase setup. Here in Europe three phase setup are common even in homes unlike North America where it’s split phase system and 60hz.

1 hour ago, Carlos said:

I still think that a split-sync is much better than 2 inverters in parallel. Either split-sync or three phase setup. Here in Europe three phase setup are common even in homes unlike North America where it’s split phase system and 60hz.

I'm starting to think this would be better for me as well.  The only thing that was making me consider the 240s was being able to charge @240v with a generator, but really, it sounds like id be better off with a dedicated external high efficiency charger designed for lifepo4 and just let inverters just be inverters. I've always used external chargers before anyway. Of course that would,( i presume?), render those cool genstart functions a moot point.

Well, this is Genetry Solar, so...not necessarily!

If you set the System Mode to "Inverter Only" (as opposed to the default "Normal"), the inverter will not switch to AC mains.  But the voltage genstart trip thresholds (and the generator start function) will continue to operate.  This is kinda a requisite, as the inverter has to be able to start the generator in order to get AC Input power to switch to in the first place.

Well that's pretty cool then. 

ok i have the rev.c board installed and just upgraded to 1.16r about 3 weeks ago. however i am still having charging problems. i have tried to calibrate the inverter and not having much luck. i am running 240v on the input side. this is whats going on  i can measure 1.6 amps on each phase of the input the screen says 1.6 on the main input. when i go into the calibration settings i can not adjust the amps to match what is going in or out of the inverter the closest i can get the input or output is about 2.6 amps (when my clamp meter reads 1.6 amps) and the inverter likes to charge and then kick off at any random time. i know i have mismatched hull sensors.  Is it possible that my sensors are to far out of spec. to calibrate the inverter correctly.  or am i just doing something wrong. i did the testing with the inverter in pass-through and about a 150w load on one phase.

Probably just a matter of clarification here--from the unwritten manual, so bear with me 😉.

The calibration screen will display amps in 120v amps.  In other words, your 150W load = 150W / 120v = 1.25A.  This is what the inverter should display on the Calibrate Readings screen.  "Calibrate Readings" page should only read double that (i.e. 2.5A) if you have a 300W load on 240v (=300W/240v = 1.25A in 240v amps, but 300/120v = 2.5A in 120v amps.)  In "Pass-Thru" mode with a resistive load (i.e. light bulb, heater, etc.), you should be able to get both amperage readings fairly close to each other AND what's measured outside of the inverter.  You shouldn't have to max the config levels out.

I hope the sensors are not too far out of spec--though it does seem to me that we got shipped all the sensors that failed PJ's accuracy specs...haha, gotta love it.

Is there some way I could contact you via video call to sort this out?  It would have to be later tomorrow afternoon/evening (EST) or later in the week if necessary for you; you can PM me with specifics.

i am off work today so anytime your available you can call me. the forum was acting strange last night. when i would log on id get a message saying forum not available right now. also i am having trouble sending you a message. i have tried about 4 times now and it just kinda buffers and just sits and buffers but doesn't send.  i did my test last week sometime so my numbers may be off a little (i may have been running a bigger load). i will re check somethings today and try and message you later. you may still have my number i did send it to you a few months ago.

Ok forum is probably working fine. I think I'm having some issues with my internet setup. I can send messages fine on my phone.

For the record: the issue turned out to be the generator that was providing power to the inverter.  The governor was not maintaining the engine RPMs at higher loads--so the more load on the generator, the lower the output frequency went.  The inverter in 60Hz mode trips out at ~55Hz...and the genset was dropping down to 54Hz under load (causing the inverter to trip).

Temporary solution was to adjust the inverter frequency calibration down ~2Hz (i.e. 57Hz nominal) so the inverter wouldn't trip out until the genset reached 52Hz.  (Long term solution would be to check out the generator's governor so it maintains 60Hz output under load.)

Tighten the governor spring a little so unloaded is 61-62Hz. (You can bend the Tab the spring connects to a hair to accomplish this)
Those springs wear out eventually.