Bow Thruster Dims The Lights

[RichandHelen]

When I use my bow thruster all of my lights dim - from my nav lights to the image on my GPS. What's going on?

[svHyLyte]

The device evidently pulls so much power, there's a voltage drop in your overall electrical system.

[ranger58sb]

And the bow thruster is apparently serviced by the house bank of batteries.

Could also be that the battery bank capacity is insufficient for overall loads, or maybe the batteries are old or undercharged or both...

-Chris

[rwidman]

Is this something new or has it always done this?

If it's something new, your batteries are probably getting weak or they are not being charged properly. It's also possible that the connections between your batteries and the distribution panel or ground are loose or corroded.

If it's always done this, it could be any of the above or it could be that you never had enough battery capacity in the first place.

Bow thrusters draw a lot of current.

[savoir]

That's normal. Electric winches and the anchor windlass would do the same.

[Mariano]

What type, brand, etc..? Coud be that brushes are worn out or dirty, short circuit in the winding, loose contact, dying batteries, lack of grease,and the list goes on forever.

In your car, when your battery is low or dying and you hit the start lights go down, but when it's ok you wont notice it.


Mariano

Fair winds

[jamhass]

Many folks install a dedicated battery close to their thruster and/or windlass to both ensure full voltage at the motor and minimize the drain on their main electrical system.

[paulajayne]

Originally Posted by jamhass

Many folks install a dedicated battery close to their thruster and/or windlass to both ensure full voltage at the motor and minimize the drain on their main electrical system.

^^^^^^^

This

[chris4911]

Mine has 4 dedicated gel batteries and still does it, along with heavy use of winches or windlass

[wiekeith]

Originally Posted by RichandHelen

When I use my bow thruster all of my lights dim - from my nav lights to the image on my GPS. What's going on?

Does it also do it when the engine is running?

[Mr O]

Glad you brought this subject up because my thruster has been pulling the voltage down to 8.3v when activated for a few seconds. Fully charged bank of 5 AGM batteries. SidePower folks say it should be above 9.6, if I recall. The motor is off to be checked, although it looked like the brushes were fine, the shaft spun smoothly, as does the prop shaft. Relay contacts were dirty, but would that cause huge power draw? FYI, the batteries load tested fine and connections good. 8 large cables go from batteries in aft cabin to bow thruster, so I don't suspect much line drop. I'll try to post again once I get word from Imtra whether there was an issue with the motor.

[rwidman]

Originally Posted by jamhass

Many folks install a dedicated battery close to their thruster and/or windlass to both ensure full voltage at the motor and minimize the drain on their main electrical system.

Electrically, this is much more complicated than this post would make it seem.

[Mr O]

Originally Posted by jamhass

Many folks install a dedicated battery close to their thruster and/or windlass to both ensure full voltage at the motor and minimize the drain on their main electrical system.

Yes, the tech support folks at Imtra (SidePower) suggested that I consider installing a separate battery bank near thruster. Not deep cycle, but starting batteries. Makes sense since it's similar situation to starting an engine: high cca's and short load cycle.

[rwidman]

Originally Posted by Mr O

Yes, the tech support folks at Imtra (SidePower) suggested that I consider installing a separate battery bank near thruster. Not deep cycle, but starting batteries. Makes sense since it's similar situation to starting an engine: high cca's and short load cycle.

Read my post above. You can't just run a pair of wires to it from the other batteries to keep it charged.

Unless your boat has always done this, something has changed and you should find and fix it.

You mentioned something about "large wires" from the batteries to the thruster. Perhaps the wires are just not large enough. Ask the folks at Imtra what gauge the wires (cables) need to be for that distance and back.

so I don't suspect much line drop

Don't "suspect", measure the trop at the battery and the drop at the thruster.

[Mr O]

Originally Posted by rwidman

Read my post above. You can't just run a pair of wires to it from the other batteries to keep it charged.

Unless your boat has always done this, something has changed and you should find and fix it.

You mentioned something about "large wires" from the batteries to the thruster. Perhaps the wires are just not large enough. Ask the folks at Imtra what gauge the wires (cables) need to be for that distance and back.

Don't "suspect", measure the trop at the battery and the drop at the thruster.

True, but this is a factory install which has not had problems until recently. The gauge of the wires is not suspect.