As I mentioned in the meeting the other day I am looking for fast blow fuses for the disconnects, and I want the highest DC voltage rating along with the highest DC current interrupt rating (AIC, see many posts ago for that). First a reference on what the different classifications mean:
https://www.fusesunlimited.com/glossary.aspxThe fuses that came with some of the units were type RK5, which is a slow blow type, good for motors. I need the opposite, a fast blow to protect the equipment, wire, and possibly my house. Type RK1 is what is appropriate for my purpose as it is designed to stop current flow, not just sever the connection and hope for the best.
I also mentioned I expected to pay a bunch of money in fuses. The ones I had seen previously were over $100 per fuse, and I need 8. After spending some time digging I have located a fuse model that sells for a fair bit less than the others, at some vendors.
Ferraz Shawmut A2K100R, also Mersen A2K100R
Unlike the More common Bussman or Littlefuse brands that I can't find for below 100, these seem to retail for under $40 in at least two cases.
https://www.allfuses.com/a2k100rhttps://www.pacificcoastbreaker.com/a2k100r-100a-250v-class-rk1-fast-acting.htmlI haven't ordered any yet but will be soon and will update who I went with and if they stole my money or not
![Smiley :)](https://www.fveaa.org/forums/Smileys/default/smiley.gif)
There were also some of these for sale on Ebay, but they weren't that much cheaper for something that could be easily counter-fit.
That fuse is also rated at 250 VDC unlike the Littlefuse version that I had found that was only rated at 125VDC, while costing 1/3rd the money.
In other somewhat related news re-reading the NEC 625.34 in the 2005 book and noted that when dealing with EVSE greater than 60 amps it's disconnect has to be able to be "locked in the open position", and needs to be "accessible", or close to the charging station.
"locked open position" means that you can apply a padlock to the disconnect to prevent someone from turning it back on. This requirement is quite common in industrial settings where equipment maintenance teams can turn off equipment, and lock it, so they can work on it without worrying about someone turning it back on. This is a feature in the disconnects I have installed.