AquaticsLive Posted August 16, 2022 Share Posted August 16, 2022 How hard is it to switch a GS 6k 12V inverter to single phase from split phase? I have been looking at my electrical setup and it may work out better if I make my new inverter a single phase inverter and use my old PJ as a split phase and make the two systems separate. My rooftop AC is single phase about 2k Watts so that is pushing the one phase of the inverter pretty hard, I put the blower and some other loads on the other phase. The balance of the loads is not equal though so thinking I may be better off using the new GS with single phase so it can handle it better. I am using 12V I know that may come in to play with internal heat of the inverter, although don't worry about the power feeding it. 1 Quote Link to comment Share on other sites More sharing options...
Sid Genetry Solar Posted August 16, 2022 Share Posted August 16, 2022 3 hours ago, AquaticsLive said: How hard is it to switch a GS 6k 12V inverter to single phase from split phase? I have been looking at my electrical setup and it may work out better if I make my new inverter a single phase inverter and use my old PJ as a split phase and make the two systems separate. My rooftop AC is single phase about 2k Watts so that is pushing the one phase of the inverter pretty hard, I put the blower and some other loads on the other phase. The balance of the loads is not equal though so thinking I may be better off using the new GS with single phase so it can handle it better. I am using 12V I know that may come in to play with internal heat of the inverter, although don't worry about the power feeding it. Basic steps: void inverter software warranty access the System Setup menu (CFG -> System -> System Setup), and set the inverter output voltage to 120v. (Yes, the inverter can safely run here with no loads before the hardwire reconfiguration. The same cannot be said for reconfiguring a single-phase inverter to split-phase!) Pop the lid, and reconfigure the transformer output leads. NOTE: The chassis AC lines are only 10AWG; these will need doubled up to handle the doubled amperage. If you're not using AC input, you can "borrow" a line from AC Input to double up both Hot and Neutral output.) Obviously, I'm quite willing to help you via video call if necessary to make sure it's reconfigured properly 😉. However, that being said...if you aren't having inverter heat issues in current split-phase config, then I don't think you'll have anything to gain by switching to single-phase (though you would lose the auto-switching AC input ability). Transformer losses will be exactly the same regardless of the battery voltage spec (12 / 24 / 36 / 48v) or output configuration (single or split phase). Same can't be said for the FETs though between the battery voltage options. Yes, the transformer won't particularly like imbalanced loads--BUT only if you're exceeding 3kw/side. Otherwise (quite unlike HF inverters), the inverter doesn't care about load balancing. Even so, it'll probably be able to sustain 4kw on a single phase (no load on the other) without overheating, but that can't be guaranteed. Quote Link to comment Share on other sites More sharing options...
AquaticsLive Posted August 16, 2022 Author Share Posted August 16, 2022 10 minutes ago, Sid Genetry Solar said: Yes, the transformer won't particularly like imbalanced loads--BUT only if you're exceeding 3kw/side. Thanks, then I won't worry about it. I just didn't want to beat up the new inverter. Well if it was better to go single I would bug Sean and ask him to switch my wiring to single phase before he builds it. Sounds like I would loose more things than it would be worth. Thanks for spending the time to explain that in such detail. Quote Link to comment Share on other sites More sharing options...
Sid Genetry Solar Posted August 16, 2022 Share Posted August 16, 2022 10 minutes ago, AquaticsLive said: Well if it was better to go single I would bug Sean and ask him to switch my wiring to single phase before he builds it. If you don't already have the inverter, it'd be part of the normal build/setup process--so not a problem at all. Quote Link to comment Share on other sites More sharing options...
NotMario Posted August 16, 2022 Share Posted August 16, 2022 I can't see much point in switching to 120v for any North America structure. Unless you're doing split-sync... Maybe in a big RV... they probably don't do split-phase in those things. Get the legs as balanced as possible. Might be worth considering switching to 240v AC - probably not a cheap solution, though... I think it would be more efficient though, which is always nice. Quote Link to comment Share on other sites More sharing options...
AquaticsLive Posted August 16, 2022 Author Share Posted August 16, 2022 (edited) 56 minutes ago, NotMario said: Might be worth considering switching to 240v AC Its all setup with 240v AC as much as I can just the Rooftop Air conditioner's compressor is single phase so it only grabs from that one line making it not as balanced as I would like. I have it setup in an ambulance converted to a work truck/RV I have all my tools in there and place to sleep when I am on the road. Edited August 16, 2022 by AquaticsLive Quote Link to comment Share on other sites More sharing options...
NotMario Posted August 16, 2022 Share Posted August 16, 2022 (edited) Silly me, when i said AC i meant changing the Air-Conditioning compressor to 240v. LOL. Horrible acronym to use on a forum like this. That would likely require a new unit - so expensive. I don't suspect your unit has a dual-voltage motor, but you might look at the wiring diagram for it to see if it can be wired for 240v input. (could be possible if the unit is also sold in other countries) So this is in an RV? Now i understand why it's a 120v unit... But the RV has split-phase wiring? Or have you customized the wiring? Cause, if this is for an RV, and the RV was originally 120v-only, i'd have Sean change you to 120v. It'll be simpler and not confuse the hell out of people who may deal with it in the future. By the way... pet peeve; split-phase is single phase - it's just two different legs on the same phase relative to a neutral. Two-phase isn't really a thing. Edited August 16, 2022 by NotMario Quote Link to comment Share on other sites More sharing options...
NotMario Posted August 16, 2022 Share Posted August 16, 2022 Also, excuse my ignorance - don't know how an ambulance is wired from the factory. I'd imagine there's some kind of inverter involved, but no idea if they'd do full-blown split-phase... I tend to prefer keeping things as close to the way they'd come from the factory as possible, hence if it was 120v-only, i'd tend to want to keep it that way. Quote Link to comment Share on other sites More sharing options...
dickson Posted August 17, 2022 Share Posted August 17, 2022 My rooftop AC is single phase about 2k Watts so that is pushing the one phase of the inverter pretty hard, I put the blower and some other loads on the other phase. The balance of the loads is not equal though so thinking I may be better off using the new GS with single phase so it can handle it better. I would keep the GS 6kw split-phase 240vac . Use L1 for the 120vac air conditioner since it is less than 3000 watts and connect the other appliances to L2 . The PJ inverter can handle any other loads if needed . You say its all setup with 240v AC as much as I can just the Rooftop Air conditioner's compressor is single phase so it only grabs from that one line ... so make L1 that line . 1 Quote Link to comment Share on other sites More sharing options...
dickson Posted August 19, 2022 Share Posted August 19, 2022 Thanks, then I won't worry about it. I just didn't want to beat up the new inverter. Well if it was better to go single I would bug Sean and ask him to switch ... NO do not tell Sean to switch but keep it 240vac split-phase . Later you can parallel another 240vac split-phase GS 6kw and and run all your other 240vac tools on 12kw parallel mode and not have to watch the unbalanced line . Quote Link to comment Share on other sites More sharing options...
AquaticsLive Posted August 19, 2022 Author Share Posted August 19, 2022 (edited) On 8/16/2022 at 8:14 PM, dickson said: Use L1 for the 120vac air conditioner That is how I have it setup now, so I will leave everything the same. The PJ only has the one current sensor and its on L1 so that is where I put the main load so I can watch it. The PJ handles it without issues, I may have been worrying too much about the new GS inverter coming. Budget is tight so took me awhile to save up for a GS inverter just trying to think of anything i can do to prep for the swap. Exciting to get a new one to be honest so may be doing a little more prep than needed. Edited August 19, 2022 by AquaticsLive 1 Quote Link to comment Share on other sites More sharing options...
AquaticsLive Posted August 19, 2022 Author Share Posted August 19, 2022 On 8/16/2022 at 6:04 PM, NotMario said: no idea if they'd do full-blown split-phase... Yes it's setup real split phase 50 Amp from the Grumman Olson conversion which installed the ambulance package. Shore power is a twist lock SS2-50R and it has an Onan 6.5K split phase generator. It has a 50 Amp panel and the Onan power switching station. Way more than I will ever need, but super handy as a mobile power station lol. Quote Link to comment Share on other sites More sharing options...
NotMario Posted August 19, 2022 Share Posted August 19, 2022 (edited) 34 minutes ago, AquaticsLive said: Yes it's setup real split phase 50 Amp from the Grumman Olson conversion which installed the ambulance package. Shore power is a twist lock SS2-50R and it has an Onan 6.5K split phase generator. It has a 50 Amp panel and the Onan power switching station. Way more than I will ever need, but super handy as a mobile power station lol. Very nice. I wish all RVs were done this way, the 240v is good for high amp appliances. Keep it split phase. I think dickson is right-on. Just keep it on it's own leg. As long as the second leg won't overload, you're good. While balance is always preferable, it's not the end of world if you have some imbalance. If your PJ is working, your GS will easily do it. No sweat. Edited August 19, 2022 by NotMario Quote Link to comment Share on other sites More sharing options...
Sid Genetry Solar Posted August 19, 2022 Share Posted August 19, 2022 4 hours ago, AquaticsLive said: The PJ only has the one current sensor and its on L1 so that is where I put the main load so I can watch it. Haha. GS has two current sensors (one on the input, the other on the output), and it measures TOTAL power on both the input and output (i.e. it can see loads on L1 as well as L2). As well as being able to determine AC power direction from said sensors as well 😉. The control board in the preorder inverters DOES have a port for balance detection. Basically, it'd allow the inverter to measure "Neutral" current and see how out-of-balance a split-phase load is (a Sean request)--but I didn't include the actual current sensor in the manufacturing requirements, as it notably increases the cost for dubious benefit. If there's a load balancing issue, you'd probably notice the inverter overheating at less than full load--and said load imbalance would be very easy to identify with a clamp ammeter. Quote Link to comment Share on other sites More sharing options...
AquaticsLive Posted August 20, 2022 Author Share Posted August 20, 2022 17 hours ago, Sid Genetry Solar said: load imbalance would be very easy to identify with a clamp ammeter. I am always monitoring the loads just one of those things we do for fun I guess. Okay next question reading the manual the input power has the option of 120 or 240 both say I can keep split phase out. I am thinking on the input side I think it may be better to go with 120V since when I plugin at a job site or camp sometimes there is only a 15 Amp 120V outlet. My thought is that may work better to use the charge function when I am on the road an extended period of time. Any downside to having it setup that way? I don't plan to use ATS since my system is already setup with a manual switching box which I plan to keep setup. I can add a 120V inlet port just for the inverter to make it a clean dedicated source. Quote Link to comment Share on other sites More sharing options...
NotMario Posted August 20, 2022 Share Posted August 20, 2022 14 minutes ago, AquaticsLive said: I am always monitoring the loads just one of those things we do for fun I guess. Okay next question reading the manual the input power has the option of 120 or 240 both say I can keep split phase out. I am thinking on the input side I think it may be better to go with 120V since when I plugin at a job site or camp sometimes there is only a 15 Amp 120V outlet. My thought is that may work better to use the charge function when I am on the road an extended period of time. Any downside to having it setup that way? I don't plan to use ATS since my system is already setup with a manual switching box which I plan to keep setup. I can add a 120V inlet port just for the inverter to make it a clean dedicated source. As i understand it, the disadvantage is you can only pull 25A @ 120v = 3000W compared to 25A @ 240v = 6000W. What i would do is wire it [direct to inverter, skipping your switching box] to your 240v [presumably] 14-50p., and then rig a 5-15p/tt-30p neutral to leg 2 of a 14-50r. You can then use both types, depending on whats available to you. The inverter will automatically detect which voltage you supply it, and you can continue using your full split-phase setup, no matter which type of power you have available at the site. Of course this kind of adapter probably violates a bunch of electrical codes. But aside from having two completely separate input cables, i don't know a better way to do it. Quote Link to comment Share on other sites More sharing options...
AquaticsLive Posted August 20, 2022 Author Share Posted August 20, 2022 22 minutes ago, NotMario said: The inverter will automatically detect which voltage you supply it Ahh that is good. I didn't know that part. I can make that work then, I just wanted to make sure that I didn't need to let Sean know to set incoming to 120V. The manual is outdated a bit on that part. "240v Split-Phase SetupThis setup is most common, and allows for the choice of either 120v or 240v AC input (pleasespecify the desired AC input voltage at purchase time). Output is 120 + 120 split-phase power." Quote Link to comment Share on other sites More sharing options...
Sid Genetry Solar Posted August 20, 2022 Share Posted August 20, 2022 3 hours ago, AquaticsLive said: The manual is outdated a bit on that part. Sure is, unfortunately. Trying to keep up with all of the various aspects of a product is...quite difficult, to say the least! That manual is for 1.1r3...and I just released 1.2r0 a few days ago. @NotMario is correct; all GS inverters with a Rev. C control board (i.e. all of the ones sold this year, as well as the last part of last year) have an auto-switching AC input relay. They will auto-detect and switch between 120v or 240v input modes upon power connection (unless you disable one of the 2 input modes--in which case they'll throw an "invalid AC input alarm"). You can set different current limits for 120v and for 240v input (i.e. shore power vs Grandma's extension cord!) And yes, due to internal wiring and transformer winding limitations, maximum input current power on either 120v or 240v is the same 25A. (Obviously, this results in half the watts in 120v mode.) Quote Link to comment Share on other sites More sharing options...
AquaticsLive Posted August 21, 2022 Author Share Posted August 21, 2022 4 hours ago, Sid Genetry Solar said: Sure is, unfortunately No worries man and nice for you to confirm what @NotMariosaid. Its great we have this forum to share our knowledge. Every question I came up with someone knows the answer. You can't beat that from any other inverter company we are like a small family. 1 Quote Link to comment Share on other sites More sharing options...
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