Distributed Power Switch Box Placement

Here is yet another thing that changed from plan once I got the bits in hand: placement of the switch boxes. There are the devices that, when instructed by events on the network, do the actual switching of the target devices (lights, pumps, etc).

In the engine room there are two switch boxes: one for 24VDC and one for 12VDC. Each box can switch up to ten devices. I wanted an easy access location for adding new device wiring or overriding fuses, yet out of the way for “normal” operation. The solution was, as with the remote battery switch, to “hang” them on a custom cut acrylic bracket bolted to the backside of the aluminum panel frame that spans the width of the engine room. This puts the switch boxes at your fingertips when sitting at the workbench, yet it is recessed out of the way such that wires or lines of any sort can’t get caught on the unit. Wire from device loads, as they are added, will route behind this assembly, against the hull with the E-Board, then drop in from behind to terminate at the switch box. In the future there will be an easily removed protective front panel across the bottom that will help protect the devices.

Switch boxes lower center and left. Battery switch lower right. User interface components center.

 Another switch box is located in the forward salon under the floor. This will serve the loads that will be atop the main mast (navigation lights, anchor light, deck/spreader lights, etc). The wiring for these devices will exit the base of the mast, down the inside of compression post to the step underneath the forward salon floor, to ultimately terminate at this switch box. The box will also switch the fresh and raw water pumps for the domestic water system nearby, under the same floor.

Mast step switch box.

The mounting of the switch box is temporary for now. I need to come up with something that helps protect the device from moisture, yet provides easy access. I figure I will address that when the final floor is installed.

A few more switch boxes are planned throughout the boat. They will be added as devices continue to be installed.

4 comments for “Distributed Power Switch Box Placement

  1. Anonymous
    July 6, 2012 at 6:12 pm

    Hi Robert,

    I don't think that 'under the floor' is a good location for the box! Even if it is certified for harsh environment.
    'My locations' are chosen in order of importance from:
    1) not too difficult to reach and to wire and rewire
    2) good, at least enough, ventilation (high current = heat)
    3) shortest wire to appliance
    4) not over heat generator (engine, oven, stove …), especially if used for high currents
    Consider that I use this system (not Mastervolt) for all !
    A good location, as example, is under the mast on the BK, replacing the terminal block for mast appliance (removable), fw cabin light, saloon light etc.


  2. July 7, 2012 at 4:30 pm

    Thanks Claudio,

    Yeah, I am not thrilled about the location. I have some other options nearby. The goal is to find the balance between accessibility and wire run lengths, especially for the mast loads. I have some time to think about it. But this location is temporary to enable some testing for a couple devices.

  3. July 7, 2012 at 7:13 pm

    Hi Robert

    I'm with Claudio on this one, "High and Dry" where possible. Ref the mast, the wires on mine (except for the vhf) exit about 6ft above the base through a small drilled hole. The wires go directly to the bulkhead behind the mast, about a 10in jump.

  4. July 8, 2012 at 12:38 am

    Thanks Gerry,

    Yeah, this decision will hinge on whether we go deck or keel stepped mast (undecided). If we go deck stepped, placing the box on the underside of the deck, near the compression post, is the logical place.

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