Hi,
My Victron supplier who sold me the Lynx shunt doesn't have a 400A CNN fuse.
Is it ok to use an ANL fuse of 400A instead of the CNN?
My system has external fuses and if there is nothing else involved for the fuse on the shunt then to blow when overcurrent is flowing between battery and units then i in reality could just connect a piece of copper.
Kind Regards
One of the key things in battery systems is to ensure you have a suitable fuse located as close to the battery as possible. It guards against the possibility of an electrical short downstream of the battery that ultimately starts a fire.
As to the rating of this battery near the battery - If you are using a SLA bank then I'd suggest that the ANL substitution is ok. If you are using a lithium chemistry then I would suggest an external fuse rated for the potential short circuit currrent would be preferred over both CNN and ANL types.
See also
https://www.victronenergy.com/live/dc_distribution
Hi Kai, and thanks for your post.
I will place an external 400A batery fuse before the Lynx shunt (before it even reaches the Lynx Power In), so i don't really need a fuse inside the lynx, but i need to bridge the postitive ends inside since there now is a gap :)
And my Victron dealer has an ANL fuse of 400A.
My battery is a 380Ah Lead bank.
Sounds like you have your bases covered. Unless there's some special condition that absolutely requires the fast blow type, a slow blow should also work in this context. The most likely short circuit scenario is that you have a short circuit that is significantly in excess of the fuse rating causing it to open pretty quickly. In the more unlikely event that there is a partial short, hopefully your cable can withstand 400A+ for a reasonable period of time (enough for a fuse to blow) before reaching a dangerously high temperature.
I can't say that I can recommend on a public forum that putting in a copper busbar in place of a fuse is ok on the general principle that someone else might misinterpret in a different context and justify to themselves that they can save a few dollars on the fuse.
I would like to understand why the "lynx 1000" system is listed in the marketing literature as a 1000 amp system does not have a 1000 amp fuse for the lynx Shunt? The largest that I can find is an 800 amp CNN fuse from Littelfuse. The specs in on the Victron website indicate that the shunt can handle 1000 amps continuous. What am I missing here?
I found a fuse that I believe will work great. It is rated for 1,000 A, 100Vdc, 100 kA interupt rating (much better than CNN). These fuses are kind of expensive, but they will allow you to use the Lynx shunt to it's full potential.
Also, if the total sum of the fuses on either the left or the right side of the shunt total up to 1000A or less, then you don't need the main fuse in the shunt. In such case, you could use a copper buss bar instead.
These fuses seem to be backordered everywhere, but I'm bringing them into stock along with custom 1000A rated Copper bars (for when you don't need the fuse). They should all be in my stock within a few weeks and I'll post some pictures when they arrive.
I found that some of Littlefuse LT17 telecommunication fuses will fit inside the Lynx shunt. The attached is 800A with 100kA interrupt. It appears that with a little modification Victron could get a class t to fit inside their Lynx shunt case.
