Hi. I currently have a system that has 2 Classic 150's charging a 12 volt system. I'm increasing the size a bit and doubling the voltage to 24 volts. I'm have a terrible time finding an inverter that can run at the higher voltage. I really only need one that's 1.5kw-2kw and most I find cut off at 30 volts. I've found a 5kw inverter that goes up to 34 volts, which I'm concerned isn't enough during the EQ cycle. Any Suggestions would be great! Thanks!
you may just have to shut it down when EQing, or adjust your absorb time & voltage upwards and only EQ once a month. Depends on battery make and size and type.
Quote from: Web4Deb on June 04, 2013, 07:51:02 PM
Hi. I currently have a system that has 2 Classic 150's charging a 12 volt system. I'm increasing the size a bit and doubling the voltage to 24 volts. I'm have a terrible time finding an inverter that can run at the higher voltage. I really only need one that's 1.5kw-2kw and most I find cut off at 30 volts. I've found a 5kw inverter that goes up to 34 volts, which I'm concerned isn't enough during the EQ cycle. Any Suggestions would be great! Thanks!
I do not know the exact specifications but I have 2X Outback FX2524 24 volt inverters and they stand up to EQ up around 30 volts just fine.
Or are you using some odd batteries like Nife?
I think you are worried about non issues for any reputable inverter manufacturer.
I have been wrong before, however.
Tom
The Samlex PST-1500-24 and PST-2000-24 both have a high-voltage shutoff of 33V (and have both a GFCI and hardwire output). They're fairly reasonably priced - I picked up the 1500W for $450.
Unfortunately, I don't have my 24V system up and running yet, so I haven't tried it out.
Take a look at the COTEK S1500-124. It is good up to 32V. It is a 1500W continuous rated unit. I have the 12V version, S1500-112. I have been impressed with it. It will carry 1700W for 3 minutes until trip without more that a few volts sag on the output. It will do 1800W for about 3 seconds. I've got some pretty good test instrumentation so the above power figures should be pretty accurate. The overload trip circuitry is actually looking at watts and not the VA which is nice. Even without the power saver feature turned on the No Load consumption is only 13W which is quite good for an inverter of this size. This is for my 12V model. YMMV for the 24V model.
Would recommend that you check the specs very carefully, especially on the Cotek inverters. For example, looking at the specs of the COTEK S1500-124, the spec sheet says that the hi voltage "protection" is 30.6 volts. For flooded batteries, AGMs or cool/cold batteries, the LOW high voltage disconnect makes this model essentially useless for many, many applications, IMHO.
This entire series of Coteks all seem to have very low Hi V shutoff. Good Luck, Vic
Here is a link to the manual which should help you with following Vic's recommendation:
http://www.wholesalesolar.com/pdf.folder/inverter%20pdf%20folder/Cotek%20S1500%20manual.pdf
Input voltage range is given in Specifications section 2.2. Range given for the S1500-124 is listed as 20-32V. My actual observations with the 12V model where the range is given as 10-16V is that the HV trip is a few tenths above 16V.
I have a Cotek SK1500-124 . notice it is an SK not a S model.
The Sk does trip and goes into protection around 30.5v Definately not up to 32v. But again it is a different model so not sure how the S will perform.
matthew
@animatt.
Your observations are consistent with the published COTEK manual for your model which can be found at this link:
http://www.civicsolar.com/sites/default/files/documents/skseriesmanualaug2009-43032.pdf
For your model they give a voltage range of 21-30V so your observed HV tripping at ~30.5V is consistent.
SweetTater ..
Sorry about the mixup in the Cotek model number. I just copied the exact number in your post, and Googled that number, found a spec sheet for that inverter, referenced the Protection voltage, to confirm the low shutoff voltage. I do not know how I got to a different spec ...
And guess that you did not edit the post, changing the number ... some Forums do not note that a post has been edited ... dunno, am sure that I confirmed the number as the same as posted ... Sorry for the mixup. Vic
@Vic
You have jogged my memory about this. You may have seen exactly what you think. I remember now that when I was researching this purchase I did find a document somewhere online that had some information that conflicted with the specs in the manual. It took an email exchange with COTEK to get clarification. Searching..., yep it's still out there. I would bet you saw this or something derived from this:
http://www.wholesalesolar.com/pdf.folder/inverter%20pdf%20folder/S1500-Spec..pdf
I remember noting at the time that it was likely written and reviewed by rookies. Check out fuse data. If they can fuse a nominal 12V unit at 70A or a 24V unit at 40A and get a continuous output of 1500W they have some very clever technology ;-)
Quote from: Web4Deb on June 04, 2013, 07:51:02 PM
Hi. I currently have a system that has 2 Classic 150's charging a 12 volt system. I'm increasing the size a bit and doubling the voltage to 24 volts. I'm have a terrible time finding an inverter that can run at the higher voltage. I really only need one that's 1.5kw-2kw and most I find cut off at 30 volts. I've found a 5kw inverter that goes up to 34 volts, which I'm concerned isn't enough during the EQ cycle. Any Suggestions would be great! Thanks!
The outback 25/35-24s (fx, vx) both are 24v inverters and handle up to 34v just fine.
http://www.outbackpower.com/products/sinewave_inverter/grid_tie/
http://www.outbackpower.com/products/sinewave_inverter/off_grid/