Residential Solar Offgrid

[iSwannie]

Greetings Solar Enthusiasts,

Over the past two years my solar system has been evolving. My Solar System now consists of (2) EG4 6500ex Inverters in parallel and (9) EG4 LifePower Batteries and (36) 275w Trina / Aptos Solar Panels. I have two EMPs installed, one for solar panels and one for battery system. My HVAC condenser is running on my solar system with a SOFT-START, which is different than a HARD-START. Do your research. I am also running AC IN with these inverters without any issues. See attached picture.



First of all I want to thank Will Prowse and this forum for the support in helping me build my Off-Grid solar/battery system over the last couple years. I have learned the hard way what you SHOULD NOT do when designing a solar system ?, which gives me the education of hard knocks. It has been fun for sure and challenging at times, but rewarding while learning from scratch.

@Signature Solar https://signaturesolar.com
thank you for your products and support in building my solar system.

@Mark Millet https://youtube.com/channel/UCbL5QkQBosz67DvJgLJ6Mug
thank you for your support in getting my wiring and presentation laid out.

Most important item I can think of beginning this journey is ALL wiring MUST be the RIGHT size. Do not cut corners to save money. Do your own research and reach out to electricians as needed. Recommended 2/0 AWG from inverters to busbar and 4/0 AWG from busbar to battery busbar in rack. These wires are NOT the same as 4 AWG or 2 AWG nor 1 AWG, but are referred to as 2 naught (2/0) AWG and 4 naught (4/0) AWG.

I will gladly help anyone with questions around my hard knocks.

 

[sunshine_eggo]

Greetings Solar Enthusiasts,

Over the past two years my solar system has been evolving. My Solar System now consists of (2) EG4 6500ex Inverters in parallel and (9) EG4 LifePower Batteries and (36) 275w Trina / Aptos Solar Panels. I have two EMPs installed, one for solar panels and one for battery system. My HVAC condenser is running on my solar system with a SOFT-START, which is different than a HARD-START. Do your research.

Hi.

I've done some research, but I can't seem to find any info on the matter.

How do you put a soft start or a hard start for that matter on a condenser?

Thanks.

 

[Nobodybusiness]

Hi.

I've done some research, but I can't seem to find any info on the matter.

How do you put a soft start or a hard start for that matter on a condenser?

Thanks.

I imagine he is referring to the Microair or Hyper engineering “softstarts”.

The hard starts are usually just a bigger starting Capacitor.

Soft starts ramps up voltage slower to avoid huge inrush from the LRA.

 

[sunshine_eggo]

I imagine he is referring to the Microair or Hyper engineering “softstarts”.

The hard starts are usually just a bigger starting Capacitor.

Soft starts ramps up voltage slower to avoid huge inrush from the LRA.

I wasn't aware Microair was in the heat exchanger modification business, nor have I found any reference about regulating current flow through a heat exchanger.

 

[iSwannie]

Hi.

I've done some research, but I can't seem to find any info on the matter.

How do you put a soft start or a hard start for that matter on a condenser?

Thanks.

Hi.

I've done some research, but I can't seem to find any info on the matter.

How do you put a soft start or a hard start for that matter on a condenser?

Thanks.

Good question - I hired my HVAC company Xtreme Air Services https://xtremeairservices.com/ to install it. It is a device that is wired into the outside condenser. Here is what to know about the differences in the Hard-Start and the Soft-Start.
The hard start is essentially designed to help with units having trouble starting. They apply extra voltage (Thus the “hard start”) to help start units then a relay disengages, and the normal voltage is applied to the unit. Soft starts are designed to use a control board to slowly start the unit with less voltage and then once the unit is running the control board disengages the device and the unit runs with normal voltage. (Thus the “soft start”). I recommend talking with an HVAC service provider to ensure it will work in your situation.

 

[iSwannie]

I wasn't aware Microair was in the heat exchanger modification business, nor have I found any reference about regulating current flow through a heat exchanger.

Good questions again - I attached a picture of what was installed in the previous post. I have a Trane XLi18 4 Ton Heat Pump outside condenser 4TWX8048A1000CA and a Trane Air Handler in the attic TEM6A0D48H418AA. My house is 2500sqft.

 

[sunshine_eggo]

Okay. I guess it's not going to be funny if no one sees it. I'll clarify.

Condensers are heat exchangers.

COMPRESSORS are what need soft or hard starts.

 

[OzSolar]

Okay. I guess it's not going to be funny if no one sees it. I'll clarify.

It just loses something when you have to explain it..... lol

 

[iSwannie]

It just loses something when you have to explain it..... lol

I get it, my background are Power Plants so I get the difference but hard to break habit of terminologies.

 

[Finca Life]

Okay. I guess it's not going to be funny if no one sees it. I'll clarify.

Condensers are heat exchangers.

COMPRESSORS are what need soft or hard starts.

lol, off topic but I love your signature

 

[OffGridInTheCity]

Congratulations on you're setup! Thanks for sharing the pic of you're system / comments. To me, its FUN to see systems in operation.

I'm in year 4 of operations and agree, it's a journey. I replaced my compressor with whole-house (variable speed) heat-pump so I could heat/cool with my solar power and as a bonus the 'variable speed' has a side-affect of being 'soft start' by design.

I caught my old 1997 installed, 4-ton compressor just before being replaced


spiking at 95a on a 48v battery bank -> 12,000w AIMS. At a 50v battery this is ~375 amps which tripped my Midnite Solar 250a circuit breaker going to the AIMS. Agree the compressor was on it's last legs but still, it was a heck of spike

The heat pump 4-ton compressor maxes at 18a * 240v = 4,320w. Way smoother for off-grid solar.

 

[sunshine_eggo]

"oh no, it is a smoke.."

I owe it all to @gnubie:

DC breaker wiring

The topic of DC breaker wiring polarity (ie, which side of the breaker is the source and which is the sink) has been raised a few times on the forum. I'm not sure if this clip has been posted before, but if not this is a must for everyone to watch.

diysolarforum.com

 

[curiouscarbon]

I owe it all to @gnubie:

DC breaker wiring

The topic of DC breaker wiring polarity (ie, which side of the breaker is the source and which is the sink) has been raised a few times on the forum. I'm not sure if this clip has been posted before, but if not this is a must for everyone to watch.

diysolarforum.com

indeed, cribbed from @gnubie

hoping they are okay!! been a while

when an inverter has had enough.. it's a smoke.. ?

 

[curiouscarbon]

It just loses something when you have to explain it..... lol

what does it lose?

latent heat? pressure? temperature?

 

[DWColorado]

Greetings Solar Enthusiasts,

Over the past two years my solar system has been evolving. My Solar System now consists of (2) EG4 6500ex Inverters in parallel and (9) EG4 LifePower Batteries and (36) 275w Trina / Aptos Solar Panels. I have two EMPs installed, one for solar panels and one for battery system. My HVAC condenser is running on my solar system with a SOFT-START, which is different than a HARD-START. Do your research. I am also running AC IN with these inverters without any issues. See attached picture.

View attachment 121463

First of all I want to thank Will Prowse and this forum for the support in helping me build my Off-Grid solar/battery system over the last couple years. I have learned the hard way what you SHOULD NOT do when designing a solar system ?, which gives me the education of hard knocks. It has been fun for sure and challenging at times, but rewarding while learning from scratch.

@Signature Solar https://signaturesolar.com
thank you for your products and support in building my solar system.

@Mark Millet https://youtube.com/channel/UCbL5QkQBosz67DvJgLJ6Mug
thank you for your support in getting my wiring and presentation laid out.

Most important item I can think of beginning this journey is ALL wiring MUST be the RIGHT size. Do not cut corners to save money. Do your own research and reach out to electricians as needed. Recommended 2/0 AWG from inverters to busbar and 4/0 AWG from busbar to battery busbar in rack. These wires are NOT the same as 4 AWG or 2 AWG nor 1 AWG, but are referred to as 2 naught (2/0) AWG and 4 naught (4/0) AWG.

I will gladly help anyone with questions around my hard knocks.

Are you running the entire house as an off grid system, then using grid as only an AC source to charge batteries as a back-up? I ask because that's what I want to build and have some questions regarding how to run the panels (main and sub, not solar). I'm thinking the easiest way is to use my main as the new subpanel, and create a new main panel with only a large (50a) 240 breaker to provide AC to the 6500's. I would then route the outputs from the 6500's back to the main panel to provide 240 to both legs (120 each leg) to power the house just like it is now.

 

[iSwannie]

I selected the circuits I wanted as essential and moved those into a sub-panel. I added an interlock so my solar and utility can’t be on at the same time. This way I can swap it as needed back to utility for maintenance on the solar system. You must have some sort of interlock to prevent back charging the main panel. I also have a separate sub-panel for my inverters AC output breaker feeding the essential circuits. I ran #4 wires from main panel to the inverters AC in and use it for UPS when no solar is available and low battery voltage. There are a lot of discussions on the bonded ground that you should research. Hope this helps.

 

[iSwannie]

I selected the circuits I wanted as essential and moved those into a sub-panel. I added an interlock so my solar and utility can’t be on at the same time. This way I can swap it as needed back to utility for maintenance on the solar system. You must have some sort of interlock to prevent back charging the main panel. I also have a separate sub-panel for my inverters AC output breaker feeding the essential circuits. I ran #4 wires from main panel to the inverters AC in and use it for UPS when no solar is available and low battery voltage. There are a lot of discussions on the bonded ground that you should research. Hope this helps.

Update: I don’t charge my batteries at all with the utility (grid). I let the inverters transfer to utility (AC in) when there is no solar and battery voltage is at 25%. I only charge my batteries with solar.

 

[Skypower]

If you install a hard start or soft start kit on your air conditioner, install a new run capacitor at the same time. They are inexpensive and easy to install. Don’t even bother checking it, they only last so long. A lot of the time a bad run capacitor is the main high load problem and could cost you a damaged compressor. Make sure you de energize your system before working on it and discharge any capacitors before working on it.