Does UL-1741 standard apply to off-grid inverters

anadiner

Solar Enthusiast
Joined
Aug 10, 2021
Messages
300
Ok took awhile but I now have the complete answer.

1st) u must check your county ordinance. Most are available online but you can talk to the code enforcement office.

Mine requires everything to be UL Listed. Btw ETL is not enough nor is UL certified. UL Listed will have the UL emblem.

Big diff between 458 and 1741. UL458 is mobile like an RV, boat, etc... UL1741 is for stationary like home, cabin, shed, etc...

As far as Will: my best guess is he is paid to do videos on solar products. I say this cuz he did a video of his home system. Curious, I looked up his items and yep, all were UL Listed. And specifically his home inverter was UL1741.

All products except batteries can be UL Listed. Even on the cabling it will say UL (barely legible).

Once again, it all comes down to your county ordinance requirement. And yes, UL Listed does cost more.

Keep in mind, UL Listed is the safest. I ended up with UL Sunpower brand panels cuz they have the UL stamp on each one.

And btw, my county ordinance also required anti-reflective coating and minimum 2400pa wind restriction.

Theres also codes about roof and ground mounting.

Good luck. Took me months to research and find out all of this, much less, the items. I found the cheapest UL Listed 1741 inverter was AIMS.
 

jasonhc73

Cat herder, and dog toy tosser.
Joined
Oct 1, 2019
Messages
1,640
Location
Wichita, Kansas
UL 1741 SA is the new safety test standard certifying products which meet the rigorous requirements needed to ensure safe and reliable operation in support of grid modernization efforts. Grid support or "smart inverter" functionality will be required by Hawaii and California beginning September 8, 2017.


You can have a UL 1741 off-grid inverter. When the grid goes down, your off-grid inverter still won't detect what it is not connected to, and will not back feed the grid.
 

anadiner

Solar Enthusiast
Joined
Aug 10, 2021
Messages
300
Ok took awhile but I now have the complete answer.

1st) u must check your county ordinance. Most are available online but you can talk to the code enforcement office.

Mine requires everything to be UL Listed. Btw ETL is not enough nor is UL certified. UL Listed will have the UL emblem.

Big diff between 458 and 1741. UL458 is mobile like an RV, boat, etc... UL1741 is for stationary like home, cabin, shed, etc...

As far as Will: my best guess is he is paid to do videos on solar products. I say this cuz he did a video of his home system. Curious, I looked up his items and yep, all were UL Listed. And specifically his home inverter was UL1741.

All products except batteries can be UL Listed. Even on the cabling it will say UL (barely legible).

Once again, it all comes down to your county ordinance requirement. And yes, UL Listed does cost more.

Keep in mind, UL Listed is the safest. I ended up with UL Sunpower brand panels cuz they have the UL stamp on each one.

And btw, my county ordinance also required anti-reflective coating and minimum 2400pa wind restriction.

Theres also codes about roof and ground mounting.

Good luck. Took me months to research and find out all of this, much less, the items. I found the cheapest UL Listed 1741 inverter was AIMS.
Oh btw, there's been no complaint about my using a generator. Maybe cuz Im not connected to the grid at all. Either way, it wasn't even examined and I have noticed a lot of subcontractors use generators. I bought an AIMS converter charger for my 24v system to keep batteries charged while panel shopping. Powered it by generator but it sure saved a lot of gas doing it that way.

Generator -> charger -> batteries -> inverter -> load. Got me through a crunch.
 

ChrisG

Solar Enthusiast
Joined
Sep 23, 2019
Messages
80
Ok took awhile but I now have the complete answer.

1st) u must check your county ordinance. Most are available online but you can talk to the code enforcement office.

Mine requires everything to be UL Listed. Btw ETL is not enough nor is UL certified. UL Listed will have the UL emblem.

Big diff between 458 and 1741. UL458 is mobile like an RV, boat, etc... UL1741 is for stationary like home, cabin, shed, etc...

As far as Will: my best guess is he is paid to do videos on solar products. I say this cuz he did a video of his home system. Curious, I looked up his items and yep, all were UL Listed. And specifically his home inverter was UL1741.

All products except batteries can be UL Listed. Even on the cabling it will say UL (barely legible).

Once again, it all comes down to your county ordinance requirement. And yes, UL Listed does cost more.

Keep in mind, UL Listed is the safest. I ended up with UL Sunpower brand panels cuz they have the UL stamp on each one.

And btw, my county ordinance also required anti-reflective coating and minimum 2400pa wind restriction.

Theres also codes about roof and ground mounting.

Good luck. Took me months to research and find out all of this, much less, the items. I found the cheapest UL Listed 1741 inverter was AIMS.
@anadiner Do you know which one of Wills inverters was UL listed? Was it the MPP6548? Thought it was ‘certified’ vs Listed. Of course I may be wrong which is why I’m asking. This launguage on AIms site is also confusing about ETL vs UL.
 

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anadiner

Solar Enthusiast
Joined
Aug 10, 2021
Messages
300
I will have to find it again. If memory serves, it was growat but unsure. I did find out ul used to be called certified but to be very careful. When advertised like 'ETL that meets UL' or 'UL certified' or 'meets UL requirements', all dandy BUT no UL emblem then DONT.

I look up the tech datasheets always. Gotta check the 2400pa and anti-reflection BUT theres always a list of emblems also.

Btw, saying UL certified can be ok. I recall checking his inverter specifically (cuz I needed one) and it was UL Listed, just cost too much for me and I didnt need 3 phase and megs watts.

I will get back to u on his inverter. I saved it somewhere. LOL
 
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