Tayana -48 Owner's Manual page 97

Always turn the main power switch off because touching any
part of thruster, as an incidental start while touching moving
parts can cause serious injuries.
Always turn the control device off when the thruster is not in use.
The maximum continued usage time of the electrical thruster is
approximately 3 minutes. The electric motor has a built in
thermal cut-off switch that will shut off the electric motor if it is
overheating and re-engage it when it has cooled down some.
This should be considered when planning your maneuvering.
This also means that the thruster will limit its total running time
per time period so that you cannot count on thruster to hold you
in current and side wind for extensive periods. Depending on the
surrounding temperature etc., the thruster will be able to run
approximately 10% of the time.
Never use a thruster close to somebody in the water, as the
thruster will draw objects close by into tunnel and contact with
rotating propeller will cause serious injuries.
Never run a thruster when the boat is not in the water, as this
can damage the electric motor seriously. If the thruster stops
giving thrust while the electric motor is running, chances are that
there is a problem in the drive system. You must then
immediately stop trying to run it and turn it off.
Running the electric motor for more than a few seconds without
resistance from the propeller, can cause serious damage to the
electric motor.
When leaving the boat always turn off the main switch for the
thruster.
We advise to always keep the main engines running while using
a thruster. This will keep the batteries in a good charge
condition.
This will also give better performance to the thruster, as a higher
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