As you may know, Victron does not provide direct support to anyone except authorized dealers and distributors and the Victron distributor known as ARW Maritime has directed me to this forum. I am seeking an answer from Victron Engineering.
I am an electrical engineer and an ABYC certified marine electrician. I am seeking some support regarding an installation of a Victron BMV-712 battery monitor.
This is a marine application. I am using the standard 500A/50mv shunt supplied with the BMV-712. The battery bank that is being monitored has a bow thruster connected to the battery. The bow thruster is an intermittent load and draws well over 500 amps. Because the load is intermittent I am not worried about damaging the shunt. It will be a lot of trouble for me to disconnect the thruster negative cable from the battery and reconnect it to the load side of the shunt so I don’t want to do that if it will not help anything. What do I mean by “if it will not help anything”. The BMV-712 measures amp-hours. I suspect that when current in the shunt exceeds 500A the monitor will not accurately measure amp-hours. I suspect it will not measure amp-hours at all. If this is the case then I will not bother to connect the thruster negative cable to the load side of the shunt and I will leave it as is which is connected directly to battery negative. I understand that another system design approach would be to use a shunt with higher current rating. I have some reasons for not wanting to do that. I would rather except some inaccuracy that may come with intermittent overload of the shunt.
Victron is a fantastic engineering company and I am sure the Victron Engineering team can provide very accurate assessment of my question and a very complete answer. I am asking Victron engineering to respond to this question of where does it make sense to connect the negative cable from the thruster in this application.
