My name is Pablo Maril, I am the installer and system designer for EfergÃa, in Argentina, and have a question regarding the Kid, and oversizing it.
I have a 24V nominal system, working with 2 series of 2 Canadian CS6K-265P modules. A total of 4 modules hook up to the Kid. The system was originally designed for 3 Canadians, but our client is rising up the number of modules to 4.
The question is, since the String calculator is in 1.3 inverters, and the recomendation is that over 1.2 go to another inverter (Classic, for example), we NEED to keep costs at the lowest possible number.
It is possible to limit the current on software via the AmpLmt menu? So I could avoid adding a second inverter or going to one more expensive one.
I have 265Wp x 4 modules = 1060Wp (@STC) => 1060Wp / 24V (nominal) = 44.16A... 14.16A over the max current!
I now this is comming out in very few ocations, but: Its going to "toast" my Kid?
Sorry for my English
Thanks a lot, best wishes from Argentina.
welcome, a little terminology first.... the KID is a Charge Controller not an inverter. Inverters change DC to AC current. ;)
the Kid is limited to 30 amps output max , it will not output more than that. ???
If I understand you correctly you want to are wanting to use that to limit the output to ?? AMPS...
You will need to install another KID for more total Amps of output.
If you have a shading problem , it is possible to install more panels but the output will not exceed 30A.
The only way to get more power, Watts, out of the KID is to go to 48Vots nominal...@ max 30A.
I think it is no problem to put extra PV panels into the Kid - but as Westbranch said - the Kid controller will limit the output to 30 amps .
So yes you can use just one Kid but your output will be only 30 amps maximum.
Larry
Sorry, my mistake, I mean to say Charge-controller but my hand wrote "Inverter".
What I was looking for is to oversize-it, but not burn-it. I wrote also to support, and It`s OK to put a little more power, just have to be shure the Kid has sufficient airflow.
Quote from: Westbranch on April 21, 2017, 12:59:45 PM
welcome, a little terminology first.... the KID is a Charge Controller not an inverter. Inverters change DC to AC current. ;)
the Kid is limited to 30 amps output max , it will not output more than that. ???
If I understand you correctly you want to are wanting to use that to limit the output to ?? AMPS...
You will need to install another KID for more total Amps of output.
If you have a shading problem , it is possible to install more panels but the output will not exceed 30A.
The only way to get more power, Watts, out of the KID is to go to 48Vots nominal...@ max 30A.
That is exactly what I whant.
Dont need more power out of the kid, just a little more during the winter perhaps, but the client whats a more "balanced" system, in the visual aspect.
Quote from: ClassicCrazy on April 21, 2017, 10:51:39 PM
I think it is no problem to put extra PV panels into the Kid - but as Westbranch said - the Kid controller will limit the output to 30 amps .
So yes you can use just one Kid but your output will be only 30 amps maximum.
Larry
Quote from: pmaril on April 25, 2017, 11:00:51 AM
That is exactly what I whant.
Dont need more power out of the kid, just a little more during the winter perhaps, but the client whats a more "balanced" system, in the visual aspect.
Beyond cost dual controllers will also impose dual idle draw consumption.
If that is not an issue then 2X controllers should net you more raw power for cloud edge effect, extra sunny days or cold weather when panels put out the most and might exceed the 30 amp threshold of one controller.
Would make panel upgrades easier, as well if you increase the production the controller is already there.
Seems an unnecessary add on just for aesthetics but the customer is always right, even when they ain't!
Just from here.
Tom
When over-PVing CCs, and the CC is Limiting current, the PV input voltage will increase (compared to what the PV Vin would be if the CC was not Limiting).
This increased Vin will reduce the efficiency of the MPPT CC, at least a bit, causing some increase in the operating temperature of the CC. This is usually not a large issue, but something that needs to be considered.
In addition, when the CC is in a voltage regulating stage (Absorb, Float, or EQ), the Vin will be higher (for the same output current from the CC), than would be the case for a CC that is not over-PVed, also increasing the CC temperature.
FWIW, Vic
If your client would like much better monitoring via computer and android apps and the internet via the Midnite web based app then upgrading to the Classic charge controller is something to consider. Plus it can handle all the current too.
Larry
Pmaril.
In my experience with both the Kid and the Classic 4 panels wired 2 in series will have a input voltage of 60-70 volts where 3 in series at 105-110 volts ,the configuration with higher input voltage will cause more heating even though the 4 panels have more total power, it's the higher voltage difference between battery out volts verses p.v. Input that causes more heating so I do not use 3 panels in series on 24 volt systems. Too much voltage difference.
For a while I had 2 classics side by side , one had 12 Sharp NE-170's wired 3 series 4 banks parallel , the other system had the same 12 Sharp NE-170's wired 2 in series 6 banks parallel (due to a longer run to the second array) , the system with 3 in series the fans were constantly running where the system with 2 in series the fans rarely ran. I felt that I was cooking my classic. I changed the configuration to be 2S 6P on system 1 and walla! cooler and fans not constantly running......especially when in a absorb whn the voltage rises due to the panels being loaded less, lost a bit more power in the wire run (170 feet) but extended the service life of the Classic
I am very seriously over paneled for most situations but being so close to the Pacific Ocean, I do have some seriously cloudy/foggy weather sometimes for weeks! Sunny days I'm in absorb by 9:30-10 am and floating way before noon. Foggy days I always get to float even when I can't locate the sun position in the sky through the cloud cover.
Lesson learned, try to keep the voltage ratio lower, system life will be longer!
Dave
I Just wanted to also say thanks to all for your replies here. I have 2x2 panels with one Kid charging a 12v system and it works fine for me. The only thing I notice is the "over voltage" light comes on anytime I get a lot of sun in bulk while the Kid is limiting the output current. This is great for cloudy days and in winter.
:) :)
You will see the over voltage light come on when the kid is outputting its maximum 30 amps, even if your voltage is fine. This is normal and not a concern as long as you know that is why it is happening. Especially in areas of generically low solar performance, there is no harm over driving your PV amps a bit because you will rarely get peak performance from your panels anyway. Just be careful on the voltage side to stay within the limits of the controller, that is where you will do damage.
Hi Sunshine,
Who is actually doing development/support and firmware maintenance for the Kid? I have noticed Mario seems to have gone away as we never get responses from him concerning kid firmware features, some questions go back over well over a year now.
Thanks
Dgd
Actually the KID's OVR LED is "OVER".
Over Voltage
Over Temperature
Over Amp Limit
The Kid flickers this LED as it limits the output between 30 and about 30.3 amps thus the flicker. If you set the AMP LIMIT setting lower then it will flicker as it hits this limit and it steps over by about .3 to .5 amps and pulls back.
Over Voltage could be PV or Battery, the LCD will tell.
Over Temp usually means the KID is output amp limiting do to high heatsink temperature. You can see the temp's in the KID's TEMP MENU under MISC. Toggle between C & F using the SETUP BUTTON.
Quote from: dgd on June 02, 2017, 07:26:48 PM
Hi Sunshine,
Who is actually doing development/support and firmware maintenance for the Kid? I have noticed Mario seems to have gone away as we never get responses from him concerning kid firmware features, some questions go back over well over a year now.
Thanks
Dgd
Actually the KID is now "Feature Locked" with the final addition of Logging & Auto EQ.
Most of the SYNC Mode bugs have been fixed with the addition of some LED indicators, re-purposing the 2WK LED and ERROR LED.
Most if not all previous issues should now be fixed in FW 1856.
Mario is very involved with developing charge controller modules for the MNB17 Inverter system. Any KID features questions can be directed to me.
Quote from: WizBandit on June 02, 2017, 07:35:45 PM
Quote from: dgd on June 02, 2017, 07:26:48 PM
Hi Sunshine,
Who is actually doing development/support and firmware maintenance for the Kid? I have noticed Mario seems to have gone away as we never get responses from him concerning kid firmware features, some questions go back over well over a year now.
Thanks
Dgd
Actually the KID is now "Feature Locked" with the final addition of Logging & Auto EQ.
Most of the SYNC Mode bugs have been fixed with the addition of some LED indicators, re-purposing the 2WK LED and ERROR LED.
Most if not all previous issues should now be fixed in FW 1856.
Mario is very involved with developing charge controller modules for the MNB17 Inverter system. Any KID features questions can be directed to me.
Wizbandit -
Do you have a document that identifies all the serial output available from the Kid ? I believe that additional output was asked for since 1820 firmware but not sure if anything was ever added ?
Thanks
Larry
Quote from: WizBandit on June 02, 2017, 07:35:45 PM
Actually the KID is now "Feature Locked" with the final addition of Logging & Auto EQ.
Most of the SYNC Mode bugs have been fixed with the addition of some LED indicators, re-purposing the 2WK LED and ERROR LED.
Most if not all previous issues should now be fixed in FW 1856.
Mario is very involved with developing charge controller modules for the MNB17 Inverter system. Any KID features questions can be directed to me.
Thanks for your reply.
As Larry asked the questions that Mario never answered were mostly related to the use of the serial port and how to extract data and exactly what data items were available. There seemed to be many missing such as WBjr data values. Also Mario's explanation of the Comms protocol and the use/calculation of crc was not very clear.
There was also some feedback from MN that the current limit set at 30a could be reprogrammed for up to 40a as apparently some customer had requested this and it was being worked on. Is this now available in a firmware release?
Also what happened to the Wind version of the Kid? And the associated Kid Clipper. It's been over 2 years since this was due to be released and the release date came and went with no further info.
Last, there was a new deeper surface mounting for the Kid that was to incorporate better sized power connectors and possible Aux connections? What happened to this?
Thanks for your assistance with these questions
Dgd
dgd -
thought you might be interested in this alternative to clipper by someone in my area
http://www.windsine.org/2017/05/28/windtac-controller/
Larry
The wind version of the Kid is still kicking around in the attic over here, hopefully for eventual release. Mario has been busy at work on the new inverters so work on the Kid slowed down a bit. We do have the new, larger wall mount bracket available and it is shipping out with all new Kids. I have a meeting with Mario tomorrow, I will ask about that 40 amp thing, I do recall hearing something about it in the past but I don't remember what came of it.
http://www.midnitesolar.com/productPhoto.php?product_ID=662&productCatName=Charge%20Controllers%20-%20KID&productCat_ID=43&sortOrder=1&act=pc
Quote from: tecnodave on April 26, 2017, 08:30:04 PM
Pmaril.
In my experience with both the Kid and the Classic 4 panels wired 2 in series will have a input voltage of 60-70 volts where 3 in series at 105-110 volts ,the configuration with higher input voltage will cause more heating even though the 4 panels have more total power, it's the higher voltage difference between battery out volts verses p.v. Input that causes more heating so I do not use 3 panels in series on 24 volt systems. Too much voltage difference.
For a while I had 2 classics side by side , one had 12 Sharp NE-170's wired 3 series 4 banks parallel , the other system had the same 12 Sharp NE-170's wired 2 in series 6 banks parallel (due to a longer run to the second array) , the system with 3 in series the fans were constantly running where the system with 2 in series the fans rarely ran. I felt that I was cooking my classic. I changed the configuration to be 2S 6P on system 1 and walla! cooler and fans not constantly running......especially when in a absorb whn the voltage rises due to the panels being loaded less, lost a bit more power in the wire run (170 feet) but extended the service life of the Classic
I am very seriously over paneled for most situations but being so close to the Pacific Ocean, I do have some seriously cloudy/foggy weather sometimes for weeks! Sunny days I'm in absorb by 9:30-10 am and floating way before noon. Foggy days I always get to float even when I can't locate the sun position in the sky through the cloud cover.
Lesson learned, try to keep the voltage ratio lower, system life will be longer!
Dave
Like
Quote from: Sunshine on June 14, 2017, 07:04:47 PM
... I have a meeting with Mario tomorrow, I will ask about that 40 amp thing, I do recall hearing something about it in the past but I don't remember what came of it.
Just wondering how your meeting went. Anything about the KID and increasing the amp limit to 40? Did the customer who wanted the 40A get a version of firmware to enable this? and if so is this firmware available for those (me) who want to experiment?
dgd
Because of the ETL listing we can't change the power ratings on the KID, so it is stuck at 30a output. They tend to be picky about such things. At least at 30a output you are not overworking the CC, although knowing it has capabilities that can't be used is understandably frustrating.
Quote from: Sunshine on August 30, 2017, 01:44:03 PM
Because of the ETL listing we can't change the power ratings on the KID, so it is stuck at 30a output. They tend to be picky about such things. At least at 30a output you are not overworking the CC, although knowing it has capabilities that can't be used is understandably frustrating.
I had my Kid leak a CAP out . was repaired @ the Midnite plant by Mr S who tested it & had 40 Amp fuses in it when he tested it to max output .
VT
Quote from: Sunshine on August 30, 2017, 01:44:03 PM
Because of the ETL listing we can't change the power ratings on the KID, so it is stuck at 30a output. They tend to be picky about such things. At least at 30a output you are not overworking the CC, although knowing it has capabilities that can't be used is understandably frustrating.
Guess you are going to have to hack it dgd !
Easier to have the firmware do it for sure . Wonder if there is a way to get at sensing shunt and have the present firmware think it is putting out less power than it is ? ( yeah would void warranty I am sure )
Larry
The kid has done 40 amps in Beta. Wish it could do more than the 30 amp limit, but as said above, Certs are Certs.