I am designing my busbar system to connect several LFp batteries to a three phase Multiplus system. I could use a simple Smart Shunt for reliable monitoring the state of charge. Another option would be using the Lynx Smart BMS 500 (not the NG version).
I consider this option to create an emergency switch, to disconnect the batteries from the Multiplus system.
What would the advantage (or disadvantage) be of using the Lynx Smart BMS instead of a regular Smart shunt? This BMS contains a heavy duty DC contactor with a 500A or 1000A rating.
The BMS will not work natively, you have to buy one of the M8 battery data cables and connect this between the 2 terminals on the Lynx BMS to fool it into working. It will not provide any battery protection. When connected to the GX device, the GX device will assume you want the Lynx BMS to manage the system, you will have to change the system setup settings so that it does not use the Lynx as the controlling BMS but set it as the battery monitor. All this is outside of the designed use case so Victron support will not be available or warranted. You will still need a fully functioning BMS for cell level protection. Why not just buy a Tyco or equivalent contactor if all you want is an emergency disconnect.
Someone on YouTube advises this solution without mentioning the details you refer to. You are right, I can’t find this way of using the BMS in the manual.
I personally think the Tyco relay you refer to is inside this Lynx module. It’s one of the very few relays suitable for such application. Using independent relays also creates the possibility to switch of battery pack individually so that they are also separated from each other.