Click for Glendinning Click for Burger Click for Abeking Click for Walker Click for Northern Lights

Mystery Box in Engine Room

Discussion in 'Ocean Yacht' started by jlresq, Nov 5, 2019.

You need to be registered and signed in to view this content.
  1. jlresq

    jlresq New Member

    Joined:
    Oct 25, 2017
    Messages:
    103
    I have a 14” X 18” closed electrical box wall mounted next to my battery charger in my ER on my 56 SS. It has three switches on the outside labeled hi/low, on/off and hi/low respectively. I opened the box and found two transformers and a few relays. It has one 110v lead going in and two 12v leads coming out. Any idea what this box is for?
  2. Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    14,432
    Location:
    Fort Lauderdale
    Sounds like a battery charger or an AC to DC converter. A picture would help.
  3. jlresq

    jlresq New Member

    Joined:
    Oct 25, 2017
    Messages:
    103
    Working on the picture but if so, why would t have three switches on it —- hi/lo, on/off, and hi/low.
  4. Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    14,432
    Location:
    Fort Lauderdale
    One Hi/Lo for each 12 volt lead, and on/off for the machine itself.
  5. captholli

    captholli Senior Member

    Joined:
    Jan 4, 2010
    Messages:
    1,164
    Location:
    In The Bilge
    Please take a pic of the inside wiring arraignment and the outside face plate to make this easier .
  6. jlresq

    jlresq New Member

    Joined:
    Oct 25, 2017
    Messages:
    103
    Will do this weekend.
  7. jlresq

    jlresq New Member

    Joined:
    Oct 25, 2017
    Messages:
    103
    Here Is a photo (I hope) showing the AC line from the bottom and two DC lines from the top. The three toggle switches are not pictured but are on the left side of the box. Hope this helps.

    Attached Files:

  8. 45SS

    45SS Member

    Joined:
    Sep 12, 2018
    Messages:
    34
    Location:
    New Jersey
    Any chance they run engine room fans?
  9. jlresq

    jlresq New Member

    Joined:
    Oct 25, 2017
    Messages:
    103
    No fans in the ER. Blowers are 12V.
  10. Tashmoo

    Tashmoo New Member

    Joined:
    Oct 24, 2016
    Messages:
    58
    Location:
    Cape Cod
    block heaters
  11. Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    12,649
    Location:
    Satsuma, FL
    That is a 120Vac to 12 or 24Vac step down box.
    AC step down transformers. The relays may be for bypass or for bright / dim for the lights.
    It converts 120Vac (dockside electricity) down to a voltage (12 or 24 (32?)ACv) for interior lights.
    You may think you interior lights are DCv from the battery, but the same bulbs can run from ACv.

    Until it sells (probably never) one like it is on e-bay.
    https://www.ebay.com/itm/STAHLIN-12...972370?hash=item46a13f0452:g:jMUAAOSwZ15dqLgi
    I think this ad proposes power for electric fishing reels. Not sure a DCv motors can run on ACv. So bunk on the title of the ad.

    But, low voltage Light bulbs can run on ac or dc volts..
    Does all of your low voltage lights work off the dock, with no gen-set or inverter running?

    I had a similar system on my 34 (glass) Pequod many years ago.

    jlresq, Where is your ship hiding. If close, I can show you all about these things.

    ,Ralph
    Last edited: Nov 8, 2019
  12. jlresq

    jlresq New Member

    Joined:
    Oct 25, 2017
    Messages:
    103
    She is docked in Huntington, NY and thanks for the explanation. What are the hi/lo switches for?
  13. captholli

    captholli Senior Member

    Joined:
    Jan 4, 2010
    Messages:
    1,164
    Location:
    In The Bilge
    Look under your cockpit covering boards port and starb for 12 volt electric reel outlets or for an outlet for a gin pole with a 12v winch .
  14. Trak

    Trak Member

    Joined:
    Mar 15, 2014
    Messages:
    50
    Location:
    Lighthouse Point, FL
    .

    This is actually a AC to DC step down box. See those little square things with yellow red and black wires going to them? Those are full wave bridge rectifiers. They convert the low voltage AC from the transformer to DC. It is an unregulated chopped DC but it would work fine for lighting or electric reels.
  15. Carver440

    Carver440 New Member

    Joined:
    May 5, 2006
    Messages:
    18
    Location:
    Cleveland, OH
    It is for Electric Downriggers or reels. Had one on my Pursuit. You should find outlets somewhere near the stern, they may look like regular electric outlets, but they are there for the power fishing equipment.
  16. jlresq

    jlresq New Member

    Joined:
    Oct 25, 2017
    Messages:
    103
    If that is the case, I can just turn the box off since I never use those. So now the question comes down to whether it is for lighting or reels.
  17. Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    12,649
    Location:
    Satsuma, FL
    Trak Has good eyes. I did not see the diode packs. So it does out put a noisy DCv.
    Still could be uses for lights but electric fishing reels seems a better use now.

    I'm guessing the hi - low switches are for different voltage power reels (or down riggers).
    To know for sure, pull out a volt meter and check it all out.

    Think we all are learning something here.
    Last edited: Nov 9, 2019
  18. jlresq

    jlresq New Member

    Joined:
    Oct 25, 2017
    Messages:
    103
    Sounds good.
  19. Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    14,432
    Location:
    Fort Lauderdale
    Follow the DC wires.
  20. jlresq

    jlresq New Member

    Joined:
    Oct 25, 2017
    Messages:
    103
    Looks like electric reel outlets is the winner. Thanks to all.