Hi all,
I've been contracted to retrofit some workboats.
They're fitted with a 24V battery bank for the engine starter motors. The short circuit current for the battery bank is 10kA, the starter motors have a cold-cranking current of 1300A. Currently, the isolation between the batteries and the motors is an obsolete, manually operated switch-disconnector.
I've been asked to design a solution allowing remote isolation of the batteries so that if there is an electrical fire, the source can be disconnected from a compartment that isn't burning. Since the standards we're working to require that the point of isolation remain next to the batteries, I had planned to do this by installing new, modern switch-disconnectors fitted with shunt trips activated using a button (in another compartment) on a small fused line run from the batteries. Unfortunately, I've realised that nobody sells a reasonably sized switch-disconnector capable of breaking such a high short circuit current and nobody sells a circuit breaker with a rating high enough to avoid tripping when you crank the engines.
Hoping someone here might have an idea how to do it without designing a solution around relays with exotic insulation. Any ideas?
I've been contracted to retrofit some workboats.
They're fitted with a 24V battery bank for the engine starter motors. The short circuit current for the battery bank is 10kA, the starter motors have a cold-cranking current of 1300A. Currently, the isolation between the batteries and the motors is an obsolete, manually operated switch-disconnector.
I've been asked to design a solution allowing remote isolation of the batteries so that if there is an electrical fire, the source can be disconnected from a compartment that isn't burning. Since the standards we're working to require that the point of isolation remain next to the batteries, I had planned to do this by installing new, modern switch-disconnectors fitted with shunt trips activated using a button (in another compartment) on a small fused line run from the batteries. Unfortunately, I've realised that nobody sells a reasonably sized switch-disconnector capable of breaking such a high short circuit current and nobody sells a circuit breaker with a rating high enough to avoid tripping when you crank the engines.
Hoping someone here might have an idea how to do it without designing a solution around relays with exotic insulation. Any ideas?
