Hi,
I can’t seem to find something that says if the Enphase micro inverters play nice with the frequency shifting from the multi
My solar system is AC coupled and I have a multi 3000, upgraded to Firmware 431.
My array is 3500w big but because of odd angles I never see over 3090w so I am not to worried about the 1:1 rule
Thanks
I also searched and searched, only thing I found was references to either off or on, no in-between.
Magnum micro-inverters have a recent product that seem to do this, but I think you have to be in the 60Hz world to avail of them.
EDIT: 01/09/2019
I was contacted by the Hoymiles product manager who apparently used to work for Fronius. He said their micro-inverters do this and had to do it for VDE 4105 certification.
I added an Enphase M215 to the output of my MultiPlus a couple of months ago.
It's working, but I've be waiting to test the frequency shifting, but there has not been enough sun for the last two months or so.
Here is a screenshot of the grid configuration in my M215
I don’t think I have the M215’s but that does sound like it....will check, I know that they are around 200w each and connected to the central controller for stats etc
Never seen the screen you showed thou...
That screen is the web interface of the Envoy it's self. http://envoy_ip_address/admin/lib/grid_config/profile_display?locale=en
Try admin / admin for both, maybe your installer didn't change it ;)
It's advantage of being a hobbyist, you get to install your own stuff and make up your own passwords.
Sorry, it was worth a try. However if your installer was that good, then maybe he was good enough to select the correct grid profile for your region.
I am starting now on a similar in installation. The M215 are installed in 2013, now want to add Victron with batteries
Thank you, Rob
Since I only have the one M215 and it makes a maximum of 229W which is below my base load, it never gets a chance to cause the Victron inverter to frequency shift.
Perhaps I'll try on my test system one day, you've got me thinking now.
I set up my M215 again to examine the frequency shifting behaviour.
The M215 exhibits very basic behaviour and does not linearly derate it's output with increasing frequency.
It only has two thresholds:
1) At 51.50Hz it still produces full output but will disconnect after 90 seconds.
2) At 52Hz it will disconnect after 0.5 seconds.
There is no other action in between these limits, it's all or nothing.
I have the same kind of interogation, I dont understand realy why the multiplus-ii need to set the power point of the micro inverter with the frequency power control because when there is no loads
Micro inverter direct is power to the charger only if there is a need (this is the baseline for all microinverters)
The need is limited by the max curent setting related to the battery capacity. or it is null when the battery is fullfiled
For the same reason i don't understand the 1.1 rule for the Multiplus-ii
The max sink power is defined by the max charging current
The max source power is defined by the inverter rated power
What is wrong that implies the need of micro inverted power control by frequency shift ? There is no limit on the ccurrent on the charger side ??
You are rigth,
For my point of view there is no problem or there is something that is not clear regarding the charger inside the Multiplus
there is some information about it
The newer IQ series micros 'should' work, they can be programmed with a frequency watt grid profile. https://community.enphase.com/s/question/0D52G00004NrYMHSA3/at-what-frequency-shift-does-the-frequency-ridethrough-operate-on-the-iq7-according-to-the-data-sheet-complies-with-advanced-grid-support-voltage-and-frequency-ridethrough-requirements-but-i-do-not-see-which-requirements-are-referred-to
The older M series m190/210/215 turn off once frequency gets to a fixed value, 60.4 or 60.5 by default (in the US). They do work fine AC coupled with a frequency shifting battery inverter (my yellow brand works fine), they just trip off all at once in some conditions. Other conditions, the battery inverter will reach the threshold frequency slowly enough and just a few will trip off and it will balance out.
Your understanding of grid-tie inverters (micro inverter) is not quite correct.
Grid-tie inverters are designed to make maximum power to push back into an "infinite" load (the grid network). When in a normal grid tied situation this is not a problem, the load is always there as long as the grid is operating normally. There is never a need to limit the output of the grid tied inverter unless a problem arises such as over / under Voltage or over / under frequency.
When the MultiPlus is connected to the grid and grid-tied inverters are on the AC-OUT, the bypass relay is closed and the grid-tie inverter is connected to the grid, no need to limit grid-tie power.
When the grid has gone away the MultiPlus' inverter will run and the bypass relay will open, no connection to grid anymore. No more "infinite" load.
Grid-tie inverters cannot know that it is a MultiPlus which is making a fake grid. It will continue to work as designed, with maximum power available. This is no problem as the MultiPlus can use this energy to charge the battery if there is enough space.
Some (Fronius) grid-tie inverters can be informed via data connection of limit.
When the battery is full, where can the energy go? The grid-tie will still be making maximum power, so if the MultiPlus cannot take the energy then one thing will happen; the Voltage will increase and can go up to 273.2V (see my table below) before the grid-tie will cut off due to over Voltage.
It will be better to increase the frequency to limit or cut off the grid-tie inverter rather than allow the Voltage to go so high.
1:1 rule. A 3KVA MultiPlus has a 3KVA transformer and a power pack suited for a 3KVA transformer. You cannot expect to put 5KVA through a system designed for 3KVA, this will be an overload which I'm sure you can understand.
Unlike the grid which has controlled generation to meet demand and grid-tied inverter does not control it's generation, it goes at full power always.
Thank you very mutch for your ligths, i undersatnd now what is the problem and yant i need to do with my AP system inverters that ave'nt the frequency power function
as i have a home made tracking i will have to add frequency measurement and swich off PV regarding the frequency
