Thrusters - Recommend Battery Bank, Location, and Wire Size

Question:

Hello PYS, I am going to upgrade my boat with two bigger thrusters, the Side power SEP250 24v cca700.  How much power do I need? Is it enough with two optima blue? Does the battery need to stay right beside the thruster to make it work? I reckon that it is important with the lenght of the cable.  - Morten

Answer:

Hi Morten, you’ll need to confirm with the manufacturer to know exactly what battery bank size is recommended for your new thrusters.  Regardless of battery size, it’s advisable to have the thruster battery bank to be located as close to thruster as possible to reduce voltage drop under thruster load. The size of the wire, depends on amperage of load, generally most thrusters are wired with 4/0 wire size. Recommend going with starter type battery to maximize the cold cranking amps of the battery.  - Jeff