Installing Rooftop Project of 1,5 MW with Sungrow Rapid Shutdown Device.

[Bendesa1962]

Hi All,

I have a question about what the best and most efficient way is to install PV Modules including the Sungrow Rapid Shutdown RSD device.

First install all RSD
Then install all PV Modules
Then do all connections and cable management

Or

Install the RSD and the PV Modules at the same time
Then make the connections and do cable management


Or

Install the RSD and the PV Modules at the same time and also make the connections and do cable management at the same time


Does anybody has experience with this? For us it is the first time


Kind regards and thx in advance

Ben

[Mike 134]

Let me double check something before additional comments. You did say this will be a 1.5MW system? So, if each panel is 500 watts you'll be installing 3000 panels? Am I correct?

Thanks

[Bendesa1962]

Hi Mike,

We will instal Longi LR7-72HTHF 610 Watt PV Modules.

So in total we will install 2459 PV Modules. Each 2 PV Modules need a RSD

[J.P.M.]

For a job that size, you don't need advice from a free and mostly unvetted forum as much as you need an engineering contractor.

[Bendesa1962]

Well we are an engineering contractor. I'm just asking if there is anyone who has experiencs with this RSD device.

[Mike 134]

Your electrical contractor will install the components in the sequence he deems most productive, unless you require something different in which case the bid price will reflect that.

[Bendesa1962]

We are the electrical contractor as well. I'm just curious if someone has experience with installing the RSD of Sungrow.

[nerdralph]

For a project that size you shouldn't be using RSD modules. In addition to the cost, that's 1230 additional points of failure you are adding to the system.
You should be designing a UL 3741 system.

[Bendesa1962]

Well it's a demand of the investor. So that is out of my scope.

[J.P.M.]

Well it's a demand of the investor. So that is out of my scope.

Among my professional hats, I wore one as a project manager for the last years of my engineering career, mostly power and process engineering.
NOMB or concern, and define your responsibilities and obligations to your client as you see fit, but when I was working, I and other professionals understood that as working engineers we had not only a fiduciary responsibility to the outfits we worked for but also to the client and to our profession.
Those responsibilities to the client included, among other things, advising the client of errors/conflicts/dangerous situations/plain old dumb stuff called for as part of the project specs/terms/conditions/other requirements we were given.
Happened all the time.
Doing less makes you about the same as a paper clip.
To be kind about it, sometimes project specs/requirements are written by folks who are not as informed as may be necessary.
Sounds like the kind of situation Nerdralph is talking about.

Take what you want of the above. Scrap the rest.

[Bendesa1962]

Well I do understand what you are talking about but let me explain the situation here.


These projects go under the principle of zero investment for the factory owner.
An investor pays for the installation of the rooftop project and sells the energy to the factory owner for a price cheaper then the utility company.
This rooftop project is already totally engineered and designed.
All materials are already purchased.

Then they put the project by tender on the market for the complete installation.
That where we come in.

And this RSD device is just to first time I do run into it. All I asked if somebody has experience with a device like this.

All other advises, how good the intention is, are useless for me. I can't change the design anymore.

Still waiting for a real answer to my question,thx

Have a nice weekend.

[Mike 134]

Still waiting for a real answer to my question,thx

Have a nice weekend.

As a retired journeyman electrician one of the things we take pride in is determining the best way to install an electrical system calling on years of experience, benefiting both the customer and contractor.

In your case it's simple work just multiplied by 2000 or so. Hire someone with proven problem-solving skills. Here's a hint (install it with the least number of steps on the roof not letting prior moves get in the way of your next move)