Skip to content
View in the app

A better way to browse. Learn more.

Power Forum - Renewable Energy Discussion

A full-screen app on your home screen with push notifications, badges and more.

To install this app on iOS and iPadOS
  1. Tap the Share icon in Safari
  2. Scroll the menu and tap Add to Home Screen.
  3. Tap Add in the top-right corner.
To install this app on Android
  1. Tap the 3-dot menu (⋮) in the top-right corner of the browser.
  2. Tap Add to Home screen or Install app.
  3. Confirm by tapping Install.

Slate Roof operations in Midrand, 12kW Deye, 14 x JA Solar 555W Monos & 2 x Solar MD 7.4kWh Batteries

Featured Replies

About to start an upgrade to an existing Single phase backup & transform to a 3 phase installation with some good upgrades in terms of PV power & battery integration. Unfortunately there are not enough Solar MDs to make up a 12kW Continuous discharge but a good start. The batteries limit this installation to 10kW 3 phase output when the sun is down. 

More pics to follow...

Another slate roof to challenge ourselves on...

North is right of picture so we plan to install 7 east & 7 west on the big MPPT. There is an existing array on the North side which is not shown. 

 

Screenshot_2023-09-13-22-35-55-327_com.google.earth-edit.jpg

  • Author

This installation is an upgrade from a single phase 5kW Axpert now pairing to a 12kW 3 phase Deye. One particular aspect of interest to most people is that there are 2 x 7.4kWh Solar MD batteries and most ppl will think that this is enough to run a 12kW Deye inverter. Unfortunately not fully able to run the Deye to full capacity of 12kW. The Solar MD is not 1C. Each Battery can only deliver 5kW max power. Meaning the Deye will behave like a 10kW machine when no sun shine & no grid. 

The owner was shocked & said nobody told him about this when he purchased them. The devil is in the details...Pay attention to C rating it's important!

Screenshot_2023-09-23-08-59-07-815_com.miui.gallery-edit.jpg

Screenshot_2023-09-23-08-58-51-198_com.miui.gallery-edit.jpg

  • Author

This is a Roman tile bracket. Some of the Valsa Brackets require one to drill through the slate & then have a Gasket on both sides. I prefer a more non invasive way. After working on many slate roofs I have found that this tile bracket works perfectly. I have also advised Valsa accordingly & they admitted they did not know it could be used in this way. Provided the Bitumen seal is covering the cut area, the roof is sealed & the bracket works mechanically in the exact same way. It attaches to the Truss.

We are done with mounting the panels. 

The pitch on this roof is insane...

Screenshot_2023-09-26-18-46-56-409_com.miui.gallery-edit.jpg

Screenshot_2023-09-26-18-46-39-298_com.miui.gallery-edit.jpg

Screenshot_2023-09-26-18-46-24-897_com.miui.gallery-edit.jpg

Edited by Steve87

Awesome i love it great job Steve always love to see your diverse installs 😮‍💨scary roof gradient if you not an installer you don’t know the feeling "I want to stand as close to the edge as i can without going over" 🤣

  • Author

Thanks @TaliaB. This old installation begs the question? How on earth did they hoist those Solar MD units that high? They weigh 70kg at least. 

They also have a PV DC combiner box that is not reachable without a ladder. This is actually a legal SANS requirement. That box must be easily accessible without the use of a ladder & be unobstructed. 

I will take pics of the inside of the combiner Box. Was very interesting to see another person's idea of a PV combiner. The cables used are also not thick enough on the battery side. One more cherry on top. There is no Changeover switch present. 

The switchgear is quality though, Hager Switchgear & Dehn Surge Arrestors , so in my opinion it's not an installation where the installer doesn't know quality. Maybe just wasn't so familiar with solar. 

Very interesting stuff...

 

This is actually a legal SANS requirement. That box must be easily accessible without the use of a ladder & be unobstructed. 

You are actually 100% correct: 

5.3.8 Positioning and accessibility of electrical equipment
Electrical equipment shall be so positioned that
a) it does not impair the functioning or safety of other equipment,
b) it is readily accessible for installation, replacement, operation, testing,
inspection, maintenance and repair (see 6.6.1.9 and 6.9.4 for the main
switch). All parts of the installation shall be accessible without the need to
enter any adjoining premises (for example, in an apartment building),
NOTE Common areas (such as passages and entrance halls) are not regarded
as adjoining areas.
c) there is easy access to its location,
d) it is not likely to be physically damaged,
e) dust or moisture is not likely to accumulate on live or other parts and
cause flashover, and
f) where the distribution board is concealed by a cupboard or other
covering, the notice for live electrical apparatus referred to in annex N
shall be in a conspicuous place indicating the position of the distribution
board.

 

This is a Roman tile bracket. Some of the Valsa Brackets require one to drill through the slate & then have a Gasket on both sides. I prefer a more non invasive way. After working on many slate roofs I have found that this tile bracket works perfectly. I have also advised Valsa accordingly & they admitted they did not know it could be used in this way. Provided the Bitumen seal is covering the cut area, the roof is sealed & the bracket works mechanically in the exact same way. It attaches to the Truss.

We are done with mounting the panels. 

The pitch on this roof is insane...

Screenshot_2023-09-26-18-46-56-409_com.miui.gallery-edit.jpg

Screenshot_2023-09-26-18-46-39-298_com.miui.gallery-edit.jpg

Screenshot_2023-09-26-18-46-24-897_com.miui.gallery-edit.jpg

Always fun seeing a slate install. What's your preference for securing the cabling to the panels/roof in this case?

  • Author

I'm a strictly Bosal Galvanized pipe type of installer. The SANS code calls for it & I completely agree with it. That pipe is very strong & durable and will protect those cables for the lifecycle of the PV roof top installation. 

Edited by Steve87

  • Author

So we over the line with this installation. Was interesting to work with Solar MD batteries again. We struggled a bit to get CANbus Comms realized because we have 2 different versions of the Solar MD battery. The previous installation was a 5kW Axpert & as can be seen in the Pics this is a 3 phase Eskom Supply. The DB was a bit of a mess & non compliant even though there as a Certificate of Compliance. You can clearly see a 3 phase MCB & Isolator but there is a Single phase Neutral attached to the Isolator. So we had to rewire to 2 x Single Phase isolators. 

2 x extra days to clean this up & revert to pure 3 phase operations & carry out a Non essentials split. CoC inspection tomorrow then final pics to follow. 

Screenshot_2023-10-01-12-33-53-340_com.miui.gallery-edit.jpg

Screenshot_2023-10-01-12-32-33-826_com.miui.gallery-edit.jpg

 

Screenshot_2023-10-01-12-33-19-294_com.miui.gallery-edit.jpg

Screenshot_2023-10-01-12-33-07-837_com.miui.gallery-edit.jpg

A very compact BMS, the balancing resistors and their fets are occupying the real estate on the left, but I dont see the charge / discharge mosfets. Or is there a contactor instead? 

Does SunSynk support this BMS protocol, or is it generic Pylon? 

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

Account

Navigation

Search

Search

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.