LiFePO4 solar generators and 13.5K/15K RV AC surge watts

[ejk]

Over the past year I've been itching to buy a solar generator minimally capable of reliably powering the 13.5K BTU AC on my travel trailer. I don't need longevity, my AC uses ~1200 watts when running and will ice box my travel trailer within 30 minutes when used before bed, which is what I want to help me get a good nights sleep in the eastern Tennessee summer. Any additional cooling it can sustain after that is bonus. The problem is I've read or or watched video of numerous accounts of these devices (EcoFlow Delta 2000, Bluetti AC200MAX & Anker 767) failing to overcome the surge watts pulled by these ACs. I wish I had been saving the link for each such account but I have the latest, a YT video of an EcoFlow not able to start the AC even with an inline soft start:

.

The EcoFlow and Bluetti devices respectively advertise 5000W and 4800W of surge capability. I can't find a statement from Anker regarding the 767 surge capacity. Based on this metric I would expect the solar generators to easily handle my AC and yet other people with similar ACs report that is not the case.

What I do know is I have a Wen 56225i generator with 2250 surge watts and it can barely manage to start my AC. If I go from Fan Hi to Cool Lo then it can start but will usually fail if I go from Off to Cool Lo.

Can anyone comment on the effectiveness of these LiFePO4 solar generators to handle AC in-rush surge watts? And besides adding a soft start I wonder if there are viable techniques to help the solar generator survive the AC start phase? I have a couple of ideas: 1) A control setting on the device itself to inform it that a surge is coming and it could fully energize the inverter. Or similarly, 2) a specialized circuit breaker to install inline of a high current device like a resistive heater. Turn on the heater first then when the AC comes on the circuit breaker is designed to immediately trip when it detects sudden voltage drop. This leaves the solar generator inverter in high-output state when the AC surge demands start.

Of all the solar generators I really want the Anker 767 and the only thing holding back my purchase is this concern about AC surge watts. I am probably going to buy, try, then return if it doesn't work for me and if so I will chronicle that adventure here.

Thanks all.

 

[RCinFLA]

Most folks install a MicroAir EasyStart 364 to run a 12-15 kBTU RV air conditioner from a 3 kW inverter-generator or battery powered inverter.

Takes a 50+ amp startup surge current down to about 15 amps.

 

[jberger]

I'll second the MicroAir recommendations. We added 2 of them to our RV this spring, and it has eliminated the nuisance triping when starting or running from the inverters.

As an example, we were at a park in South Florida where the 50amp pedestal was tripping due to a weak breaker. With the MicroAir's installed, the AC units never even dropped out, the only way I knew the breaker had tripped was the TV would blink.

We also spent a few nights in Port Canaveral with no hookups and no generator hours from 10pm to 7am. The MicroAirs allowed us to use the AC's just like we had full hookups and run from the inverters overnight.

Complete game changer in terms of boondocking and they even lower the power use while the AC is running, which I didn't believe was possible but has proven to work in the real world.

 

[RCinFLA]

A normal air conditioner run capacitor is optimized for run state to provide 90 degs phase shift to auxiliary (start) winding,

An AC motor has much greater inductive loading during startup period compared to run state. The Easystart has a much larger capacitor it puts in parallel with start capacitor only during the startup period to give more rotational torque to motor. It also uses a triac to ramp the startup voltage like a light dimmer during the startup period to reduce startup current for the approximately 0.4 second startup period.

Once the motor is up to run speed it engages a bypass relay that takes it out of circuit. It has no effect on run current for compressor.

The voltage ramp is like a true soft starter. The extra start capacitor is like what you get with a hardstart kit which just has a relay to engage the extra start capacitor during startup period. Using just a hard start kit actually increases startup surge current but reduces startup time period. It is intended for situation where there is low AC voltage to compressor either due to low grid voltage or too long of wiring run to compressor.

You need both the start capacitor assist and the soft start voltage ramp to get the optimum AC single phase motor startup surge current reduction.

Just a soft start ramp will lower the current but lengthen the startup time usually tripping inverter. Just a hard start kit capacitor boost will shorten the startup period but the high peak current will usually still trip the inverter.

 

[ejk]

Highly appreciate everyone's detailed and very informative input.

I've purchased the 767 with sale code WSSPRING767 which makes it 1700+tax. Once it arrives I will see if it can handle my AC. If it can't then I will purchase the Easystart 364 or equivalent device suited for my AC and go from there. I'll update this thread as things develop to report back on the capability of the 767 to power my travel trailer, charge my ebikes, handle my wife's Keurig, and enable AC at national parks and other primitive sites during hot nights. I'm eager to pair this with my Wen inverter generator to recharge it at 700W or 1400W during the day, and I'll probably look into a 100-200W solar kit as an exploratory foray into charging this way. The reason I'm not keen on solar is we are often under a significant tree canopy where we camp.

 

[R.Koss]

Over the past year I've been itching to buy a solar generator minimally capable of reliably powering the 13.5K BTU AC on my travel trailer. I don't need longevity, my AC uses ~1200 watts when running and will ice box my travel trailer within 30 minutes when used before bed, which is what I want to help me get a good nights sleep in the eastern Tennessee summer. Any additional cooling it can sustain after that is bonus. The problem is I've read or or watched video of numerous accounts of these devices (EcoFlow Delta 2000, Bluetti AC200MAX & Anker 767) failing to overcome the surge watts pulled by these ACs. I wish I had been saving the link for each such account but I have the latest, a YT video of an EcoFlow not able to start the AC even with an inline soft start:

.

The EcoFlow and Bluetti devices respectively advertise 5000W and 4800W of surge capability. I can't find a statement from Anker regarding the 767 surge capacity. Based on this metric I would expect the solar generators to easily handle my AC and yet other people with similar ACs report that is not the case.

What I do know is I have a Wen 56225i generator with 2250 surge watts and it can barely manage to start my AC. If I go from Fan Hi to Cool Lo then it can start but will usually fail if I go from Off to Cool Lo.

Can anyone comment on the effectiveness of these LiFePO4 solar generators to handle AC in-rush surge watts? And besides adding a soft start I wonder if there are viable techniques to help the solar generator survive the AC start phase? I have a couple of ideas: 1) A control setting on the device itself to inform it that a surge is coming and it could fully energize the inverter. Or similarly, 2) a specialized circuit breaker to install inline of a high current device like a resistive heater. Turn on the heater first then when the AC comes on the circuit breaker is designed to immediately trip when it detects sudden voltage drop. This leaves the solar generator inverter in high-output state when the AC surge demands start.

Of all the solar generators I really want the Anker 767 and the only thing holding back my purchase is this concern about AC surge watts. I am probably going to buy, try, then return if it doesn't work for me and if so I will chronicle that adventure here.

Thanks all.

Over the past year I've been itching to buy a solar generator minimally capable of reliably powering the 13.5K BTU AC on my travel trailer. I don't need longevity, my AC uses ~1200 watts when running and will ice box my travel trailer within 30 minutes when used before bed, which is what I want to help me get a good nights sleep in the eastern Tennessee summer. Any additional cooling it can sustain after that is bonus. The problem is I've read or or watched video of numerous accounts of these devices (EcoFlow Delta 2000, Bluetti AC200MAX & Anker 767) failing to overcome the surge watts pulled by these ACs. I wish I had been saving the link for each such account but I have the latest, a YT video of an EcoFlow not able to start the AC even with an inline soft start:

.

The EcoFlow and Bluetti devices respectively advertise 5000W and 4800W of surge capability. I can't find a statement from Anker regarding the 767 surge capacity. Based on this metric I would expect the solar generators to easily handle my AC and yet other people with similar ACs report that is not the case.

What I do know is I have a Wen 56225i generator with 2250 surge watts and it can barely manage to start my AC. If I go from Fan Hi to Cool Lo then it can start but will usually fail if I go from Off to Cool Lo.

Can anyone comment on the effectiveness of these LiFePO4 solar generators to handle AC in-rush surge watts? And besides adding a soft start I wonder if there are viable techniques to help the solar generator survive the AC start phase? I have a couple of ideas: 1) A control setting on the device itself to inform it that a surge is coming and it could fully energize the inverter. Or similarly, 2) a specialized circuit breaker to install inline of a high current device like a resistive heater. Turn on the heater first then when the AC comes on the circuit breaker is designed to immediately trip when it detects sudden voltage drop. This leaves the solar generator inverter in high-output state when the AC surge demands start.

Of all the solar generators I really want the Anker 767 and the only thing holding back my purchase is this concern about AC surge watts. I am probably going to buy, try, then return if it doesn't work for me and if so I will chronicle that adventure here.

Thanks all.

I have a Coleman mach 15 rooftop air conditioner in a 20 foot Ibex travel trailer with the micro air soft start. I purchased the Anker 767 power house to replace a gas generator not allowed to run in Wisconsin state parks. Even with the soft start, it will not run the air conditioner. I also contacted Anker, and even though I was one week past the 30 day return policy Anker agreed to except a return only if I paid the shipping. I am going to keep the anchor 767 because it has many other uses other than running the air conditioner.

 

[R.Koss]

I have a 20 foot Ibex travel trailer with a Coleman mach 15 rooftop AC unit with the micro air soft start installed. The AC unit is 15,000 BTUs and even with the soft start the Anker 767 power house that I recently purchased will not start the compressor on the AC unit. I am about one week past the 30 day return policy and I contacted Anker and they agreed to return it if I pay the shipping. I am going to keep it as it has many other uses and it is a high quality unit. I am a little disappointed because I replaced a gas generator with this as state parks in Wisconsin do not allow gas generators. Hope this helps.

 

[ejk]

Drats, I'm hoping the 767 can successfully power my AC and will probably return it if not. The 767 arrives tomorrow (Sat Apr 15) and I intend to immediately subject it to this test. I was planning on ordering the EasyStart 364 as a contingency and I still will but I've got to make sure that it arrives and I install it before the 30-day window.

Does anyone know if there is a Kill-A-Watt style meter that can report the peak surge watts / instantaneous max-power? I have a P4400 but it doesn't tell me this. If the 767 doesn't perform I'd be willing to spend a bit of money to accurately study this failure case. Thanks.

 

[RCinFLA]

Kill-A-Watt meter does not report peak current.,

Some clamp-on current meters have a peak hold function, but many are not very accurate on their reported peak surge current. They usually read low for surge current reported.

 

[ejk]

Well my 767 arrived 3 hours ago and I charged it to 100% then proceeded to try the following:

1. resistive heater 600W, works
2. Keurig 1400W, works
3. Keurig + heater 2200W, works
4. RV AC, from Fan Hi to Cool Lo, does not work

I was expecting this outcome but was still hopeful that I would not need to order an easy start, I will order one tonight.

I also tested my Wen 56225i generator again. After not using the unit for 6 months I turned it on, waited 5 mins for it to warm a bit, then successfully went from Fan Hi to Cool Lo. I have a Power Watchdog RV surge protector I was using to monitor power usage with both the 767 and Wen generator. The Watchdog is in agreement with the 767 on power usage with difference of only <10W. When I attempted to turn on the RV AC the Anker display last reported 867W and the Watchdog said 1123W. When I retested with the Wen generator the highest value reported on the Watchdog was 1654W and the steady state power was 1270-1300W. Ambient temp outside ~50F so real easy conditions on the RV AC right now.

It is disappointing that the Anker 767 can't deal with my AC surge watts like my $400 gas generator can.

Next step is the easy start, hopefully if I order today I can have it for the weekend to do the install.

If the easy start does not resolve I will return the 767 and at least my gas generator will now have a much easier time with the AC going forward.

I see the other post regarding the reversed polarity of the unit when attaching to wall, I'll be looking into whether my unit does that as well.

 

[ejk]

Well here's some good news for me, my Coleman Mach AC has a sanctioned soft start kit available for less money with easier install: https://www.airxcel.com/softstart, https://www.rvpartscountry.com/coleman-mach-soft-start-1497-3601.html. Going to find out if the addition of this part makes my 767 viable.

 

[ejk]

I finally received and installed my "Coleman-Mach Soft Start Kit - 1497-3601" and it seems to work great. Using my Power Watchdog PWD30 and going immediately to Cool Hi I see the fan come on first with 400watts in the first 1-2 seconds then I hear the AC compressor come on much more slowly with the watch dog doing a 400W -> 700W -> 500W ->650W-> 800W -> 1100W sample reporting as I trained the soft start with 5 start up cycles. I imagine the initial "700W" is the surge and the instananeous peak power is present around there and probably much higher than 700W.

My Wen 2250i generator loves the new soft start, it has zero issues going from Off to Cool Hi even in Eco Mode.

The Anker 767 on the other hand fails horribly! Whereas prior to the softstart the Anker simply cut power cleanly, now it gets into some busted up state where the Power Watchdog reports voltage as 49V and the unit does not turn off! I was freaking out running to the Anker outside as I heard a low-frequency electrical hum coming from my AC while my phone was screaming at me about the 49V. The Power Watchdog then tripped and killed the circuit before the Anker did. Moments later the Anker tripped and went full fan for several seconds then turned off. In total the 49V state lasted around 5 seconds from the Anker, 3-4 seconds from the watchdog.

So I'm done with this unit, its instantaneous power is far inferior to even a cheap gas inverter generator. As I reported in this thread before: https://diysolarforum.com/threads/anker-767-reverse-polarity-issue.61417/ I also have the reverse polarity issue when connected to a wall outlet. I will get my shipping label from Anker for this defect and tell them to keep the unit and refund me my money.