is using FPP with fire pump and shaft alternator on maine engine's PTO possible

[bahgota]

Hello, I'm facing a problem,
we are supposed to build an ASD 31m work boat for fire fighting, supply, towing, berthing and unberthing

but the client wants a FPP and diesel driven fire pump and a diesel driven bow thruster

which we thought of fitting the Firepump on the main engine PTO and use an elecrtical bow thruster instead, and fitting a shaft alternator with higher rating than that of the boat's genset to compensate the electrical load increase,

but the problem, is it possible to fit a FPP to and engine having fire pump and shaft alternator mounted on the PTO of main engine because of speed variation,

or better to use CPP with Engine configuration and PTO genset for powering the bow thruster.will this combination would be more trustable and less maintenance.

please Advice

[Landlubber]

bahgota,

The vessel is obviously going to be in class survey, the customer request is to survey requirements, the fire pump is to be independant of the main engine, actually two are required in most cases.

Why would you want a CPP when the customer has asked for FPP? What the customer has asked for is normal..PTO driven fire pumps are not primary, but could be secondary pumps anyhow. As the boat is only small, the main engine may not even be able to power that much from PTO's anyhow, check with the manufacturer about PTP taleoff power and loading vectors.

Your last question about reliability....no, the redundancy factor is higher, maintenance is a marginal cost as the society determines the rules, the independant power source has to be there anyhow.