Electrical - Cabin Fans - Install inline 2A fuses to each cabin fan

[smr547]

Mark Miller reports that Greg Hall experienced an electrical fire on board.

1. The comfort fan in the fwd stb cabin broke away from the cabinetry.
2. (A plastic screw had worked loose due to fan vibration)
3. The fan fell, placing stress on the cable
4. The electrical cable then parted and shorted causing the wires to smolder and catch fire.
5. Despite the obvious short circuit the circuit breaker and/or fuse on the circuit failed to trip and the fire continued to burn, consuming the wire in the process
6. The wire burned into the wardrobe
7. Greg managed to extinguish the fire with a wet rag just before it disappeared behind the cabinet
8. Smoke
9. Mark reported that the fan might be connected to the house lighting circuit.

This circuit should be immediately isolated and de-powered. I'm not certain that this has been done. It seems that the fans have not been installed properly and are not correctly fused.

This is a critical incident. I think that Namadgi 3 should not sail until an electrician has effected repairs or at least made the circuit safe.

Steven Ring 23/10/23

@delcosta @CORCpete @mgrybaitis @mrmrmartin @pjwain @pcbaston

[smr547]

Allister reports that the circuit seems to be wired back to the bus bar without a fuse. This is a dangerous installation.

I'll ask Boatworks electrical contractor to check the wiring, make it safe and provide a report.

[smr547]

I removed the safe and wardrobe back panel. The fan's power line had burned all the way back to its junction with the ships lighting system. A wire tracer tool was used to track the lighting circuit back to the main switch panel where it originates from a relay and associated 25A fuse. All fuses were intact and correctly rated.

It is assumed that all fans have been wired into the cabin lighting system at the time they were originally installed.

The fan is rated at 0.27 amps consumption and the attached supply wire is barely capable of carrying 3A. Yet, it has been wired into a 25 amp circuit. This is a problem and it's not suprising that, when a short occurred, the fine wire drew enough current to start a fire and yet not enough to blow the 25A fuse.

The remaining three fans are therefore a fire hazard.

Two solutions are possible:

1. Install a separate circuit for cabin fans, switched at the control panel and fused at 5A, or
2. Install an inline "glass tube" fuse on the supply at each fan. The fuse should be 1 or 2A rating.

I recommend the second option as it is effective are lower cost.

I'll leave this issue open until the work is done.

[pcbaston]

What about using the more common blade fuses. I think the fuse panel uses these too, making spares easier. Here's the in-line fuse holder I am suggesting:

[smr547]

Sounds good to me.

[DimitD]

I have purchased necessary parts and left onboard for repair

[smr547]

Hi @DimitD,

thank you @DimitD for doing that (sorry, I missed your comment).

I'll assume the work is going to be done by one of the electrically-talented members and set #budget=$50 for the parts

[pcbaston]

Steve and Dimitri, Can you tell me what is planned for this issue. I was going to get to this issue during my booking in a week's time. Happy for you to do it before hand, but happy also to do it myself. Please advise so I can take tools and parts Paul Baston

[pcbaston]

Attempted repair. Leads on fan are too short for easy repair. I have removed to repair either at dock or home. I have also determine the best place to take of power is the cabin lamp next to fans. Fitting a fuse between lamp power and fan is feasible and recommended. All other three fans will be a straightforward affair. Just need power for solder iron/heat gun to melt solder sleeves.

[smr547]

Sounds good to me. Thank you for taking this on Paul.

[pcbaston]

I ran out of time and electricity to affect the repairs. I have removed the subject fan to home to effect a repair (replace the wire to motor). I will return it when I can soon. Also, I investigated the fan in the Port Aft cabin, which was not operating. Removing the back covers inside the cupboards is quite difficult and the electrical connections within a little concerning. See pictures: The electrician's tap into the lighting supply circuit behind the Aft Port cabin closet cover.

Looks like the 240VAC supply line was too short in reaching the GPO in the Fwd Stbd cabin.

I repaired the solder joint with a solder sleeve in the Fwd Stbd cabin thus: Solder sleeve repair in Fwd Stbd cabin closet.

and have found a safer, easier connection to attach the 'fused' fan power supply, which I will use to affect repairs: 12Vdc Lighting Supply Circuit to cabin lamps attached to closet in each cabin

Waiting on an opportunity for the vessel to be available (uninterrupted) for a day on shore power.

[pcbaston]

I have rerouted all wires to the lamp connection. Awaiting appropriate sized wire fuze holders. Temporary wiring to spade terminals has all 4 fans working. Any risk to wiring can now be seen and contained within locker away from main wiring.

[smr547]

I'll drop this to priority 2

[smr547]

Nice work Paul

[smr547]

Hi Paul,

Please address the package to

Namadgi 3 Visiting Yacht The Boat Works 1 Boatworks Dr, Coomera QLD 4209

Kind regards Steven