It seems like dc surge protection is hard to come by in a 600v 20ka and 40ka rating.

question, is a 60ka rating ok to use for your solar pv DB as I was quoted on a 40ka but my suppliers don’t have stock, only 60ka

the drop off voltage is the important part, that needs to be as close as possible to the protection rating you require.
In SA the closest you get is usually the DC 600v ones, and be sure to use dc for dc and ac for ac on the AC side usually 275volt ones

eglow normally have stock (I buy from there a lot)
https://e-glow.co.za/collections/battery-accessories/products/spd-2p-600vdc-20ka-40ka-surge-protector?utm_campaign=gs-2022-06-01&utm_source=google&utm_medium=smart_campaign&gclid=EAIaIQobChMI_KKLyJzh-AIVEWHmCh0lGAzkEAQYBSABEgIPGfD_BwE

ACDC usually have stocl but mostly just the ac ones

1 minute ago, WannabeSolarSparky said:

the drop off voltage is the important part, that needs to be as close as possible to the protection rating you require.
In SA the closest you get is usually the DC 600v ones, and be sure to use dc for dc and ac for ac on the AC side usually 275volt ones

eglow normally have stock (I buy from there a lot)
https://e-glow.co.za/collections/battery-accessories/products/spd-2p-600vdc-20ka-40ka-surge-protector?utm_campaign=gs-2022-06-01&utm_source=google&utm_medium=smart_campaign&gclid=EAIaIQobChMI_KKLyJzh-AIVEWHmCh0lGAzkEAQYBSABEgIPGfD_BwE

ACDC usually have stocl but mostly just the ac ones

So the supplier has 2 pole 600v dc surge protectors, but they come in 20, 40, and 60ka ratings.  I’m just worried about which is rating to get because the 40ka is out of stock, even my local AC/DC is out, so basically I just need to know if the 600v 60ka is okay or is the last rating to high

AFAIK those are surge protectors, they will drop excess voltage to the ground when they experience surges, 60 ka should be fine as long as the voltage drop is in spec.

Remember if you experience a DIRECT lightning hit no amount of surge protectors are going to save you.
If you are in a lightning area then you need to explore further options for mitigating DIRECT lightning strikes.

@WannabeSolarSparkyso what I think I’ve learnt after watching some videos on ka rating is that if you have a 60ka surge protector it means that it will control a surge of power that’s 60ka once but will control a surge of 10ka 6 times before you would have to replace the surge protector. So the positive about having a smaller ka rating is that if you have small surges you would know there is a problem quicker than if you had a bigger ka rating. So a smaller ka rating would potentially bomb out before a bigger problem is caused possibly damaging equipment.
 

I don’t know, does this sound correct or am I just talking kak 😂

Have you ever notice my username on the forum

Its WANNABE Solar Sparky.

If you want definitive answers that can stand up in a court of law then maybe nudge the actual sparkies for more accurate answers

I only speak from what I have researched and youtubed 🤣

And a bit of trial and error diy.