Keto 3 with 300/315A Fuse Links?

Anyone know where I can buy a Keto size 3 with 315A DC fuse links as a battery isolator in the George, Western Cape area, and what a reasonable price is?

If not available in this area please recommend a reputable online retailer.

If not a Keto what else do guys use for a battery isolator with similar current specs?

If you dont come right, please let me know, I can have it delivered to you from PE for R4334 inclusive.

Other options is Moulded case breakers with the same rating but they are selling for roughly R6k excluding delivery.

I was wondering if you had 1 or more batteries? That is a big DC disconnect with some very thick cables needed.
If multiple batteries then maybe 2 or 3 smaller units?

Thanks Jaco but I ended up finding something. Fuse links and disconnector cost me around R1700 all in. Now the question is, is this a case of “goedkoop koop is duur koop” or will I be ok?

I have very little experience with Swan’s products and am a bit weary but the guy at the shop promised me there won’t be contact resistance/running hot problems, it is DC rated and all the big installers buy these from them.

I ended up going for a 250A seeing as I don’t typically run at more than max 170-180A. The 300A rating was just because the Multiplus II 8kVA manual recommends a 300A fuse for that 15kVA short burst peak capability and the Freedom Won 10/8 has a continuous/peak current rating of 200A/300A on its pre-fitted 50mm cables (only 1 per neg 1 per pos). With the loads I run I am yet to see such peaks.

It is mostly just for a disconnect and perhaps overcurrent redundancy on both pos/neg to remain compliant seeing as the FW already has a built-in breaker.

If I may, 2 questions:

  • Do you know what this greasy substance is they put on the contacts, it seems almost like soldering flux or DC4 insulating grease? I don’t see why they would use an insulating grease as it could increase contact resistance if it doesn’t burn off quickly? Did a spot check with multimeter and it is not conductive.

  • Is it ok to use a gG rated fuse which has a slower time-current curve than for instance a gS or these gBat fuse links https://www.dfelectric.es/wp-content/uploads/2021/11/NH-gBat-1500V-fuse-links-range-battery-protection.pdf ? I am guessing the FW breaker would trip before the NH gG fuses despite them being 250A rated. Then again I am just after a disconnect so doesn’t really matter and these fuses will only ever work if the FW breaker fails (hopefully never)?




Hi @mmaritz , just a baby Freedom Won, please refer to my reply to Jaco for details. 1x50mm cables initially seemed small to me too but the specs are what they are on the Freedom Won and it came pre-fitted with these cables, manual states 200A/300A continuous/peak current rating.

You should be fine with this. Keto is very expensive compared to Swan and Chint, but I quoted you on the keto as per your first post. We also sell Chint and Swan, and the price you paid is market related.

Did you buy from OmniSolar or Power Hour, or some place else?