 |
Korg Forums
A forum for Korg product users and musicians around the world.
Moderated Independently.
Owned by Irish Acts Recording Studio & hosted by KORG USA
|
| View previous topic :: View next topic |
| Author |
Message |
19naia
Platinum Member
Joined: 29 Nov 2012
Posts: 1216
|
 Posted: Thu Jun 11, 2020 4:47 pm Post subject: Question: type of 120-volt power supply. |
 |
|
Happy beach day everybody.
My new place has solar based electricity supply.
Solar panels to charge controlled batteries.
Then batteries to a modified sine wave inverter that makes 110 or 120 volts AC current.
Have not shipped my Kronos over yet but it will ship as soon as we work out the packaging.
But i am wondering if the power supply will be ok for when i plug in power for Kronos.
The inverter says it is rated for all electronics, or household type appliances or devices with the right volt-amp limits.
It has issues with some high voltage battery chargers used mostly for cordless power tools.
I assume any UPS commonly used with Kronos, is simply a battery pack with a charger+charge control, and an inverter.
So my solar power system, i assume should be the same as using a UPS with a 2400 discharge DCvolt-amp capacity and a 2000 ACvolt-amp output capacity to Kronos and the other devices i midi pair with Kronos.
The link below shows the inverter i have. A German brand?
https://www.donrowe.com/Krieger-KR2000-p/kr2000.htm?gclid=Cj0KCQjwrIf3BRD1ARIsAMuugNvqe31HxnBHzMFjiFr5KFd4NDPcG_dGqTYYR5iYPlTZTWevcco2OC4aAvWJEALw_wcB
Can i get any comments with first hand experience using solar+battery+inverter electricity supply with kronos? |
|
| Back to top |
|
 |
KK
Platinum Member
Joined: 13 Oct 2016
Posts: 1422
|
| Posted: Thu Jun 11, 2020 8:45 pm Post subject: |
|
|
Hi there,
One of the important qualities of an UPS or inverter is its output wave, which should be as close as possible to a sinewave. Since manufacturers are often vague about this and mention things like "sinewave stepped approximation" or in your case "modified sine wave", the best is to look at it on a scope screen or find such visual documentation about your particular inverter.
In theory, the power supply type in the Kronos should handle such an AC source without problems. But in practice, when you plug a Kronos to a basic UPS, it only switches to its pseudo sinewave when power is unstable or a brownout, etc. To run your Kronos on a pseudo AC sinewave for hours might be a different story. Unless, again, your inverter gives a good quality output, closer to a sinewave than what I saw coming out from certain other brand units. Some manufacturers (like APC) offer a warranty covering damage caused to anything plugged on their units. If you worry, you could also contact yours to see what they say.
Similar power sources are found in luxury vehicles like coach buses. They offer a very clean output (quite close to a true sinewave) and are very safe but as a comparison, cost thousands of dollars. |
|
| Back to top |
|
|
AntonySharmman
Approved Merchant
Joined: 16 Oct 2010
Posts: 3598
Location: Hellas
|
| Posted: Thu Jun 11, 2020 11:21 pm Post subject: Re: Question: type of 120-volt power supply. |
|
|
| 19naia wrote: | But i am wondering if the power supply will be ok for when i plug in power for Kronos.
The inverter says it is rated for all electronics, or household type appliances or devices with the right volt-amp limits ...
Can i get any comments with first hand experience using solar+battery+inverter electricity supply with kronos? |
Kronos PSU is a Switching Mode Power Supply as the 95% of your LPD electronic gear nowadays , that is working with any kind of
AC or DC voltage from 90 up to 400 Volts of any AC waveform Sine , Square , triangle or modified sine and really don't care about
it since it rectifies any voltage waveform to pure DC with extensive filtering , that is required for first stage power transformation ,
so the best option is always DC voltage.
For instance , I had supplied Kronos directly from 4 X 24V solar panels in series (around 110V) and worked like a charm , but in your
case inverter's output is just fine and definitely you do not need any UPS for any valid reason.
I've designed a solid box with Lithium - Phosphor batteries and an 1KW full bridge SMPS (7 Kgr) that produces 270V DC that I supply
Korg Pa4X & a pair of EV 400W (D-Class) self powered loudspeakers and I can gig for fun in full power in a desert place/beach electricity
free for 4 hours !
This Krieger is a cheap modified sine wave inverter , for your gear is fine but not advised to be used with induction loads and old
devices that use vintage iron transformers.
_________________
Music Conductor - Sound Engineer & Developer - Automotive SMPS/RF R&D - Electronics Engineer
PaSeries Demos - WavesArt.eu - KorgPa.gr <> Facebook
Keyboards : Steinway-D, Kronos X, Pa5X 76, Pa4X 76, Montage M7 , Roland-XV88, Emu3,Emax II,Synclavier II,Yamaha DX Series, ΟΒ-8V |
|
| Back to top |
|
|
19naia
Platinum Member
Joined: 29 Nov 2012
Posts: 1216
|
| Posted: Fri Jun 12, 2020 4:20 am Post subject: Re: Question: type of 120-volt power supply. |
|
|
[quote="AntonySharmman"] | 19naia wrote: | Br]
Kronos PSU is a Switching Mode Power Supply as the 95% of your LPD electronic gear nowadays , that is working with any kind of
AC or DC voltage from 90 up to 400 Volts of any AC waveform Sine , Square , triangle or modified sine and really don't care about
it since it rectifies any voltage waveform to pure DC with extensive filtering , that is required for first stage power transformation ,
so the best option is always DC voltage.
For instance , I had supplied Kronos directly from 4 X 24V solar panels in series (around 110V) and worked like a charm , but in your
case inverter's output is just fine and definitely you do not need any UPS for any valid reason.
I've designed a solid box with Lithium - Phosphor batteries and an 1KW full bridge SMPS (7 Kgr) that produces 270V DC that I supply
Korg Pa4X & a pair of EV 400W (D-Class) self powered loudspeakers and I can gig for fun in full power in a desert place/beach electricity
free for 4 hours !
This Krieger is a cheap modified sine wave inverter , for your gear is fine but not advised to be used with induction loads and old
devices that use vintage iron transformers. |
Thanks much. Really relieving to know that.
What about powered speakers or monitors? Are they ok for modified sine-wave inverters? I already understand the possible issue of interference buzzing/humming mentioned in the manual for the inverter.
I had induction load problems with a water pump i added, and i assumed induction was because the pump motor had wire coils to make rotation magnetically.
Speakers or monitors have coils that make motion magnetically.
Maybe the initial power draw is the difference. The pump definitely used overcurrent at startup.
12volt DC pump, so i moved it directly to the batteries, with a 15amp breaker on the positive lead. |
|
| Back to top |
|
|
AntonySharmman
Approved Merchant
Joined: 16 Oct 2010
Posts: 3598
Location: Hellas
|
| Posted: Fri Jun 12, 2020 9:56 am Post subject: Re: Question: type of 120-volt power supply. |
|
|
| 19naia wrote: | What about powered speakers or monitors? Are they ok for modified sine-wave inverters?
I already understand the possible issue of interference buzzing/humming mentioned in the manual for the inverter. |
You have to investigate (specs) that self - powered speakers have SMPS PSU (transformer-less) where things will works accordingly to above written ,
and modified sine will not affect at all audio.
Now in case of PSU with 50-60Hz toroidal mostly transformer (much havier loudspeakers) , interference depends of scaled analysis of sine simulation
waveform shape which is difficult to find without a spectrum analyzer / oscilloscope , but in most of times parallel connection of one 10μF/400V
no-polarity capacitor at inverter output will better improve sine waveform shape.
No-permanent magnet pumps or air-condition/refrigerator compressors have 4 times higher power than stated at start up , they create magnet field
with sine AC so it's difficult to create a solid field with modified sine and will work stressed !
12V solar systems have very low efficiency 'cause of high current losses and if you want to upgrade later your system , try to use 24V configuration
with a decent pure sine wave inverter & batteries.
_________________
Music Conductor - Sound Engineer & Developer - Automotive SMPS/RF R&D - Electronics Engineer
PaSeries Demos - WavesArt.eu - KorgPa.gr <> Facebook
Keyboards : Steinway-D, Kronos X, Pa5X 76, Pa4X 76, Montage M7 , Roland-XV88, Emu3,Emax II,Synclavier II,Yamaha DX Series, ΟΒ-8V |
|
| Back to top |
|
|
19naia
Platinum Member
Joined: 29 Nov 2012
Posts: 1216
|
| Posted: Fri Jun 12, 2020 3:55 pm Post subject: Re: Question: type of 120-volt power supply. |
|
|
| AntonySharmman wrote: | | 19naia wrote: | What about powered speakers or monitors? Are they ok for modified sine-wave inverters?
I already understand the possible issue of interference buzzing/humming mentioned in the manual for the inverter. |
You have to investigate (specs) that self - powered speakers have SMPS PSU (transformer-less) where things will works accordingly to above written ,
and modified sine will not affect at all audio.
Now in case of PSU with 50-60Hz toroidal mostly transformer (much havier loudspeakers) , interference depends of scaled analysis of sine simulation
waveform shape which is difficult to find without a spectrum analyzer / oscilloscope , but in most of times parallel connection of one 10μF/400V
no-polarity capacitor at inverter output will better improve sine waveform shape.
No-permanent magnet pumps or air-condition/refrigerator compressors have 4 times higher power than stated at start up , they create magnet field
with sine AC so it's difficult to create a solid field with modified sine and will work stressed !
12V solar systems have very low efficiency 'cause of high current losses and if you want to upgrade later your system , try to use 24V configuration
with a decent pure sine wave inverter & batteries. |
Thanks again.
Yes my plan is to finish with a permanent solar energy system. My inverter now is temporary.
I have 4 quality AGM batteries, each 100amps. 4 batteries is the max in parallel at 12v output. Will switch to 24v arrangement when i get more batteries.
Have also a decent 12v/24v MPPT charge controller on its way in the mail.
Then will eventually buy a permanent inverter with a charger that connects to my generator.
I have the quiet Honda EU2200i generator, that uses inverter technology and made to work with everything from power tools, to electronics.
I will get either Magnum or Outback inverter+charger unit.
Good quality, 24/48 volt inputs only and made for household hard wired installation.
And not a bad deal Magnum or Outback inverters, even at usd-$1700.00 for 3KV-4KV. They last for decades. |
|
| Back to top |
|
|
AntonySharmman
Approved Merchant
Joined: 16 Oct 2010
Posts: 3598
Location: Hellas
|
| Posted: Fri Jun 12, 2020 11:10 pm Post subject: |
|
|
Fine , I've designed the whole systems of hybrid solar & wind systems for my home and sea home and I have free energy for over 10 years.
I use pure sine net-metering but I also use 24V system of 2000 Ah AGM batteries only as UPS utility that also regulates power loss from wind
generators and sudden clouds Grid Tie Inverters MPPT point failure.
Although all gear has been designed and constructed by me , I use as spare one Outback 2,5KW/150V/80A MPPT controller that is the best ever
commercial product I have ever used and I strongly suggest it.
I haven't used/tried combined Outback inverter modules , but I suppose they will work pretty well ...
Contrary , 12V installation is only for mobile systems and 2KW peak power with extremely power loss and low efficiency , just imagine that 2KW
clear output requires continues 185A from batteries if you estimate low efficiency and overall power loss ...
Even for 1KW equipment's consumption , the 12V system will definitely cost more in energy and cables than 24V system configuration , strictly
my professional advice.
_________________
Music Conductor - Sound Engineer & Developer - Automotive SMPS/RF R&D - Electronics Engineer
PaSeries Demos - WavesArt.eu - KorgPa.gr <> Facebook
Keyboards : Steinway-D, Kronos X, Pa5X 76, Pa4X 76, Montage M7 , Roland-XV88, Emu3,Emax II,Synclavier II,Yamaha DX Series, ΟΒ-8V |
|
| Back to top |
|
|
19naia
Platinum Member
Joined: 29 Nov 2012
Posts: 1216
|
| Posted: Mon Jun 15, 2020 6:14 pm Post subject: |
|
|
| AntonySharmman wrote: | Fine , I've designed the whole systems of hybrid solar & wind systems for my home and sea home and I have free energy for over 10 years.
I use pure sine net-metering but I also use 24V system of 2000 Ah AGM batteries only as UPS utility that also regulates power loss from wind
generators and sudden clouds Grid Tie Inverters MPPT point failure.
Although all gear has been designed and constructed by me , I use as spare one Outback 2,5KW/150V/80A MPPT controller that is the best ever
commercial product I have ever used and I strongly suggest it.
I haven't used/tried combined Outback inverter modules , but I suppose they will work pretty well ...
Contrary , 12V installation is only for mobile systems and 2KW peak power with extremely power loss and low efficiency , just imagine that 2KW
clear output requires continues 185A from batteries if you estimate low efficiency and overall power loss ...
Even for 1KW equipment's consumption , the 12V system will definitely cost more in energy and cables than 24V system configuration , strictly
my professional advice. |
Yes i knew 12 volt was the most inefficient, but i decided to compromise because i have few batteries and the solar panels charge the batteries full in half a day on sunny days. And then the rest of the day the solar panel output is rejected and wasted.
Right now, even if i move to 24volt, i will still be making surplus power that gets wasted by the charge controller after the batteries fully charge.
On full cloudy days, my battery charge is still enough but goes into deficit if a second cloudy day follows. So i run the generator for a few hours to keep the charge up. Also i never discharge my batteries below 12.3 volts dc reading, even on the most cloud covered days.
So i decoded to just spend the small amount on the portable 12 volt Krieger inverter so i can also use it in my car away from home.
Will use it until i get more batteries and then i will buy the permanent 24v or 48v inverter by Outback or Magnum.
I was told by other people as well, that Outback is the best inverter, but also told that Magnum is long lasting and they offer 4KW at lower price, and Magnum inverters can be paired such as stacking two magnum inverters to double the output.
Outback spec sheet says nothing about stacking and their output options don’t go as high as Magnum.
Magnum 4KW = same price as Outback 3.5KW at sources i found to buy from in USA. |
|
| Back to top |
|
|
AntonySharmman
Approved Merchant
Joined: 16 Oct 2010
Posts: 3598
Location: Hellas
|
| Posted: Wed Jun 17, 2020 10:16 am Post subject: |
|
|
The inefficiency of 12V configuration is at converting 12V to 220V (for 110V is less) and not actually at batteries charge where
factor is close and also transfer cables diameter is extensional at 12V compared to 24V , 4 times bigger for the same voltage drop.
AFAIK Outback inverter modules can be unlimited connected in parallel , but maybe this has been changed.
_________________
Music Conductor - Sound Engineer & Developer - Automotive SMPS/RF R&D - Electronics Engineer
PaSeries Demos - WavesArt.eu - KorgPa.gr <> Facebook
Keyboards : Steinway-D, Kronos X, Pa5X 76, Pa4X 76, Montage M7 , Roland-XV88, Emu3,Emax II,Synclavier II,Yamaha DX Series, ΟΒ-8V |
|
| Back to top |
|
|
19naia
Platinum Member
Joined: 29 Nov 2012
Posts: 1216
|
| Posted: Wed Jun 17, 2020 5:00 pm Post subject: |
|
|
| AntonySharmman wrote: | The inefficiency of 12V configuration is at converting 12V to 220V (for 110V is less) and not actually at batteries charge where
factor is close and also transfer cables diameter is extensional at 12V compared to 24V , 4 times bigger for the same voltage drop.
AFAIK Outback inverter modules can be unlimited connected in parallel , but maybe this has been changed. |
It will take four battery linking cables to connect my 4 batteries in 24volt configuration.
I use six cables now to link the 4 batteries in 12volt configuration.
Cheaper cost for battery linking cables if i go 24volt configuration.
My wire to the charge controller and solar panel, is quality 10AWG gauge wire.
10AWG is under-sized for my 12volt x 30amp solar panel array.
If i reconfigure my solar panel array to 24volt current, my 10AWG wire will be over-sized and that means better efficiency and safety.
I looked up the Outback guide sheet for maximizing efficiency in a system.
Now i understand exactly what you mean about the better efficiency at 24volt or 48volt for the larger solar and battery banks.
When the time is right, i will get a few more batteries and then i will get outback 3.5KW inverter/charger. I found that Outback does stack multiple inverters, even more than Magnum inverters.
So Outback is the best option even if a bit more expensive than Magnum.
The time will be right to upgrade, if my 12volt inverter fails, or my power use increases to the stress limits of my 12 volt inverter, or power use grows to 200% of my solar panel maximum supply.
It could be tomorrow, or it could be next year. |
|
| Back to top |
|
|
voip
Platinum Member
Joined: 27 Nov 2014
Posts: 3776
|
| Posted: Wed Jun 17, 2020 6:26 pm Post subject: |
|
|
| AntonySharmman wrote: | The inefficiency of 12V configuration is at converting 12V to 220V (for 110V is less) and not actually at batteries charge where
factor is close and also transfer cables diameter is extensional at 12V compared to 24V , 4 times bigger for the same voltage drop.
AFAIK Outback inverter modules can be unlimited connected in parallel , but maybe this has been changed. |
I need a bit of convincing that the differences between systems having 12V or 24V inputs and 110V or 220V outputs are necessarily very large, provided the systems are adequately specified and installed in the first place, and well maintained during use. The efficiencies quoted by various manufacturers for their inverters, be they 12V or 24V input and 110V or 220V output, are essentially the same, and why shouldn't they be, since single device MOSFET RDS(on) figures of ~1milliohm are now commonplace, and devices are generally used in parallel in high power inverters. Inverters should ideally be placed close to the battery, so leads lengths are consequently very short, leading to relatively low losses there, provided the connecting cables and links are adequately specified. One of the largest sources of inefficiency in battery to mains systems is the use of high power inverters during times of low power consumption, but that doesn't really depend much on whether the input is 12V or 24V and the output is 110V or 220V.
. |
|
| Back to top |
|
|
AntonySharmman
Approved Merchant
Joined: 16 Oct 2010
Posts: 3598
Location: Hellas
|
| Posted: Thu Jun 18, 2020 5:20 pm Post subject: |
|
|
Do not confuse voltage controller regulation input voltage with final 12V or 24V batteries charging output voltage ...
If panel MPPT controller works with max 18V input then you have to use only 12V panels in parallel , each panel distribution must use
10AWG cables and master transfer cables should be min 4AWG that is extremely expensive if long , contrary if your MPPT controller's input
voltage is 150V , then you can use any panel you like in series up to 150V and 10AWG cables are fair for any voltage over 100V/3,5KW.
Now what is the low efficiency part of low batteries voltage like 12V ?
It's obvious that this is the inverter component that has an extra loss of 10-20% compared to 24/48V systems and as a SMPS designer
I can explain the reason that this happens in simple words but the rule is "the smaller the voltage conversion ratio the less the losses"
Firstly , switching mosfet that are working in lower voltages have 4 times higher RDS(on) than stated in DC , in hard switching with
currents over 10A per branch , also >150A current pulses applied on a regular transformer with voltage ratio over 18 , will lead it to saturation
and mosfets will be extra stressed with more losses & thermal heat.
The increased internal voltage drop of mosfet plus extra voltage drops of required short 6AWG cables might lead for instance to over 1V
voltage drop that is essential for an 12V system , where in 24V will be lower than 0,4V and not important for overall transformation to 220V.
My reference is for both low frequency transformer & HF single or multiple transformer inverters with unipolar PWM AC output.
12V to 110V convertion is more reliable with lower losses though , since voltage ratio is <10
Just consider of why electric cars are working with over 400V , serial batteries voltage configuration and not with simple 12/24V batteries.
Commercial product's rating is never stated at hard switching in 12V to 220V transformation over 50% of their claimed max power !
For instance a manufacturer claims that his 12 to 220V 3KW inverter has an efficiency of 90% and this can be true at a rated power of 200W
but when you will test it at hard switching of 3KW , efficiency will be close to 75% unlike the same rated 24V inverter that will be over 85%.
The only way to reduce this loss in 12V low voltage systems is combined inverters of low power like Outback brand that's why I recommend them.
Just for the story
_________________
Music Conductor - Sound Engineer & Developer - Automotive SMPS/RF R&D - Electronics Engineer
PaSeries Demos - WavesArt.eu - KorgPa.gr <> Facebook
Keyboards : Steinway-D, Kronos X, Pa5X 76, Pa4X 76, Montage M7 , Roland-XV88, Emu3,Emax II,Synclavier II,Yamaha DX Series, ΟΒ-8V |
|
| Back to top |
|
|
19naia
Platinum Member
Joined: 29 Nov 2012
Posts: 1216
|
| Posted: Fri Jun 19, 2020 4:40 am Post subject: |
|
|
I used to have a much bigger 12 volt battery system and barely got better watt hours compared to my 4 batteries today.
After 4 batteries strung in line, charge and discharge efficiency drops a lot.
My old one had 12 batteries and seemed to drain fast and give me use of very little that was drained.
Although i do have better batteries today, AGM, they don’t last as long as well maintained flooded batteries. Flooded batteries is what i had in my old large battery bank. |
|
| Back to top |
|
|
AntonySharmman
Approved Merchant
Joined: 16 Oct 2010
Posts: 3598
Location: Hellas
|
| Posted: Fri Jun 19, 2020 11:40 am Post subject: |
|
|
Single 2V cells are always bigger in KWh than equivalent solid AGM battery and Energy speaking , the KWh sum is always the same under
any voltage configuration of same batteries !
_________________
Music Conductor - Sound Engineer & Developer - Automotive SMPS/RF R&D - Electronics Engineer
PaSeries Demos - WavesArt.eu - KorgPa.gr <> Facebook
Keyboards : Steinway-D, Kronos X, Pa5X 76, Pa4X 76, Montage M7 , Roland-XV88, Emu3,Emax II,Synclavier II,Yamaha DX Series, ΟΒ-8V |
|
| Back to top |
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
