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Advice on an SPD (and a few other questions)

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I recently did a DIY off-grid install in my cottage in the bush. This includes:

2 x 405 w JAsolar panels (each connected with its own 6mm cabling to fusebox then to the Easysolar) in parallel

Victron Easysolar 1600/24v/100/50 with dongle

2x 200Ah Gel batteries

Battery balancer 

Keto Disconnect with 120A fuses

Fuses x 4 @ 10A

It incorporates PV fuses for each PV panel (fuses on each line so 2 per panel), a Keto disconnect for the batteries. The EasySolar Inverter incorporates a small AC distribution board with AC breakers and Earth Leakage breaker. I have 2 earth spikes installed by a registered electrician (including house wiring) and everything is earthed, PVs, Inverter etc.

So I asked professional advice and requested a paid inspection and prior to any inspection was advised that I needed an SPD (based on photos of the install). This was for surges and NOT lightning protection. So I have a few questions

1. Is an SPD necessary for an off-grid installation particularly for one of such modest size? Wheres a surge going to come from with the closest Eskom 2km away! 

2. If I do indeed require an SPD what size? Number of Poles? Type?

3. I was advised that an Electrical Engineer would need to sign off...........the call out fee is more than 5k before the inspection takes place.

4. That the use of sprague (flexible conduit) was not permissible for the DC cabling between PV fuse box to EasySolar (the rest is in conducting in the wall) and that this needed to be put into trunking. Seriously? Ive seen many gallery installations that have sprague.

Im not trying to second guess the professional here, just it does seem unusual to my untrained mind and would really welcome some comment! If im being a bit thick that's fine I can accept this and "kak and betaal!" I should say that everything works like a dream thus far. The Easysolar really was easy to install.

So look forward to comment!

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4 minutes ago, Gremlin said:

1. Is an SPD necessary for an off-grid installation particularly for one of such modest size? Wheres a surge going to come from with the closest Eskom 2km away! 

Depending on where you live, sometimes you should have SPDs on your PV modules. Then you'd use one of these per PV string:


Where there is AC involved, you'd put one of these before the inverter:


Where there is no grid connection, I too wonder why they'd want a surge arrestor. The Multi (at least last time I looked) have MOVs on the output already (which has the same function). If they insist, however... put the SPD after the inverter and BEFORE the RCD.

But find out exactly where it is needed... PV or AC.

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