question

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northcaptain asked

Ampere interrupting capacity fuse requirement for Victron Smart Lithium.

Fuses are classified by their Ampere Interrupting Capacity = AIC. Class T fuse = 20 000 A MRBF fuse = 10 000 A ANL = 6 000 A I've been searching if there is any mechanism inside a Victron Smart Lithium to limit the current to the 2C that is described in the manual, but i have not found. Neither any Victron recommandation for fuse type. As per ABYC rules, any wire more than 7 inch (17.5 cm) need to be protected by a fuse. MRBF fuse have the possibility to be installed directly to the positive battery screw. But do they have sufficient AIC ? Could someone from Victron explain what is the recommended fuse type AIC or Class T for the interrupting requirement of a shorted Smart Lithium ?

Lithium Batteryfuses
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2 Answers
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dc-marine answered ·

Same question here. Does Victron recommended the use of MRBF on their Smart Lithium batteries over the ABYC E-11’s 20,000 AIC minimum rating requirement (Class T) when dealing with battery banks that require a minimum of 10,000 AIC and/or when short-current value cannot be established ?

E-11 quote:

11.10.1.2.3

For batteries or battery banks with a CCA rating greater than 2200 CCA or 500 amp hours, battery overcurrent protection shall have a minimum ampere interrupting capacity (AIC) rating as follows:


11.10.1.2.3.1

at least as great as the battery manufacturer’s short circuit rating, or


11.10.1.2.3.2

20 kA at 125 VDC or higher, if a battery manufacturer’s short circuit rating exceeds 10 kA.


I’m asking because I’ve come across two installations so far by Pacific Yacht Systems that are using MRBF to individually fuse each Victron Smart Lithium batteries to a buss (6x 12/100ah and 5x 24v/240ah), but without a main Class T fuse after the bussing of all batteries. I do not believe this practice to comply with ABYC E-11 but I’m curious to hear thoughts from others.



2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

dc-marine avatar image
dc-marine answered ·
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

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