Installing a Sunsynk inverter

**Isetech** · 07-Aug-22, 11:09 AM

The unit has arrived. Now we start the process of setting up the unit ready for installation.

First thing I removed the mounting bracket ready to get templates made, one for my workshop wall and the modified version.

Why a modified version, cooling, everyone talks about the importance of cooling, then you receive an inverter with a heat sink on the back of the unit which is 3 mm off the wall, really, I would have thought a little more consideration would have been taken in account for the cooling. The first modified bracket will be longer (top to bottom) and have a space of at least 50 mm away from the wall to allow for cooling.

I a have also considered making along bracket which will support the inverter and battery with a 100 mm gap at the back, this will also allow me to fit small fans with temp control and hide the trunking or any wires I need to go up the back, that way there is no crossing of wires in the trunking.

**Isetech** · 07-Aug-22, 11:20 AM

We all talk about AC and DC separation, as I remove the cover, the DC isolator for the PV and the AC main switch are mounted right next to each other. Come on Keith, I thought you guys would have read the some of the regs and paid attention to little details like this.

I would have moved the first entry gland on the right hand side over to the left and fitted the AC on/off switch away from the DC. Maybe the little wires to and from the the AC switch are DC or low voltage, but we will only know as we dig deeper and learn about the unit.

**Dylboy** · 07-Aug-22, 02:44 PM

Another thing with DC and AC seperation is that I see you have these AC and DC combined protection boxes. Now I am not sure if there is a plastic sheet between the two compartments and then what is the description of SEPERATION ? What makes something separate...? Pvc insulation in my view electrically seperates...?

Sent from my CPH2197 using Tapatalk

**Justloadit** · 07-Aug-22, 05:06 PM

Originally Posted by Isetech

Why a modified version, cooling, everyone talks about the importance of cooling, then you receive an inverter with a heat sink on the back of the unit which is 3 mm off the wall, really, I would have thought a little more consideration would have been taken in account for the cooling. The first modified bracket will be longer (top to bottom) and have a space of at least 50 mm away from the wall to allow for cooling.

I a have also considered making along bracket which will support the inverter and battery with a 100 mm gap at the back, this will also allow me to fit small fans with temp control and hide the trunking or any wires I need to go up the back, that way there is no crossing of wires in the trunking.

Cooling in the terms referenced to a heatsink is about the movement of air to remove the heat from the heatsink. The smaller the gap between the heatsink and the wall, the better the effect, as it then acts as a chimney causing a small wind to occur. Moving the heatsink far away from the wall changes the way the air flows over the heatsink, and you lose the chimney effect, and the faster moving air over the heatsink. There was thought put into the design of the Sunsync inverter.

A similar question would be, does a black anodised heatsink work better than a natural colour anodised heatsink?
Actually there is no difference because it is about surface area exposed to the environment, and black costs more but does look nicer.

**Justloadit** · 07-Aug-22, 05:10 PM

Originally Posted by Dylboy

Another thing with DC and AC seperation is that I see you have these AC and DC combined protection boxes. Now I am not sure if there is a plastic sheet between the two compartments and then what is the description of SEPERATION ? What makes something separate...? Pvc insulation in my view electrically seperates...?

Sent from my CPH2197 using Tapatalk

The seperation of the AC and DC once in the equipment has no safety value, ultimately the DC negative, and the Mains Neutral are seperated by the volt drop across a diode, or 0.7V, so seperating the incoming AC/DC has no benefit other than a higher cost.
Generally any DC switching done in the inverters are control signals, the actual heavy work is done by the power devices, such as IGBTs and FETs.

**Derlyn** · 07-Aug-22, 05:32 PM

When justloaded speaks things electronic, I listen and take note.

The chimney thing does make sense.

My braai always smoked us out until I reduced the size of the chimney and lengthened it .. got faster air flow and problem solved. Much the same as a jet stove. I think they refer to it as the venturi effect. The smaller the gap, the faster the air/liquid flow.

**Isetech** · 08-Aug-22, 05:38 AM

Interesting, This is what I love about this forum.

If I understand this correctly, even if I build a cabninet, I must make sure I have a solid panel at the back of the inverter covering the heat sink to ensure air movement between the fins. One of the new plates I laser cut today, must go from the bottom of the heat sink to the top of the heat sink.

The plan was to put the inverter at the top a DB with all the differnet electrical components, fuses, isolators etc in the middle and the battery below. I am going to can that idea until I get a battery. The battery will also require cooling, it wont help if the battery is installed below the inverter and all the heat then go up. Maybe look at mounting ot the side.

If you install a 5 kva Sunsynk inverter with a heat sink it could void the warranty if you mount trunking directly below or anything above the heat sink. I see there is a temp probe in one of the packets, I think it is for the battery.

Apparently the 8.8 kva doesnt have a heat sink, but rather fans on the side, we will look into that, one day when I get one to tinker with.

**Isetech** · 08-Aug-22, 05:41 AM

Originally Posted by Justloadit

A similar question would be, does a black anodised heatsink work better than a natural colour anodised heatsink?
Actually there is no difference because it is about surface area exposed to the environment, and black costs more but does look nicer.

Now you got me thinking, that would look so cool with a black heat sink, when I install my own personal unit, I think I am going to get anodised black, the same colourt as the cabinet frame.

**Isetech** · 08-Aug-22, 05:43 AM

I am learning as I go, so feel free to set the record straight.

**Isetech** · 08-Aug-22, 05:57 AM

Taking the cooling into consideration, today I start looking at how I plan to move the DC isolator and on/off switch out from under the unit, without making any structual modification to keep the warranty. I want the new elctrical cabinet designed specifically for the this inverter to bolt directly to the bottom. I will get it built at a local panel builder who is certified to build electrical panels.

If I fit a DC isolator into the elctrical cabinet mounted below the inverter, there will be no need to have one under the unit.

Someone said to me that customer dont want to spend money on the electrical par tof the install, the way I see it, if you have have taken the step to piss R 150 k against the wall what another R20k to make it look good and be functional., with emnough space to add more circuits and even the equipment for the EV charger, smart devices and all the otehr stuff people are adding to their properties. The old days of those silly 1 tier DB are like fax machines.