Click for Westport Click for Nordhavn Click for Cheoy Lee Click for Walker Click for Cross

electronics protection

Discussion in 'Electronics' started by comship, Sep 7, 2007.

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

    comship Senior Member

    Joined:
    Jan 27, 2007
    Messages:
    174
    Location:
    Greece
    We are currently building a new 32m Yacht in Italy. The Yacht shall feature BUS system controlled by AMX products. Our past experience has shown that during the change over from one generator to another or from a generator to shore power, the instant abnsence of current creates problems to these electronic devices. of course the incorporation of UPSs would solve the problem but we would need more than 500 kg of UPSs and batteries. Could anybody suggest any other way to protect these devices?
  2. K1W1

    K1W1 Senior Member

    Joined:
    Sep 30, 2005
    Messages:
    7,390
    Location:
    My Office
    Hi,

    If it is the changeover from shore to ships power causing you problems then it can be overcome by setting up a seamless transfer system, this does not require 500kg of batteries.

    Are you using any sort of Shore Power converter?
  3. comship

    comship Senior Member

    Joined:
    Jan 27, 2007
    Messages:
    174
    Location:
    Greece
    Off course but my concern is changing between the three generators ( Two ONAN 2x 40kW and 1 x 22.5 kW)
  4. yotphix

    yotphix New Member

    Joined:
    Jan 5, 2007
    Messages:
    97
    Location:
    Southern California
    I'm reasonably certain that an Atlas system can be configured to provide automatic seamless transfer between generators.

    Is it the nav electronics you are concerned about? They should be running of the house bank anyway so that they will function for a time even without gen or shorepower no?
  5. K1W1

    K1W1 Senior Member

    Joined:
    Sep 30, 2005
    Messages:
    7,390
    Location:
    My Office
    Hi,

    The generators should be able to be setup by the PMS ( Power Management System) to transfer seamlessly, it is related to the paralleling feature.

    I am assuming here that you can parallel and load share with your generators.

    I would also advise that you install a good quality power filter/ line conditioner in the line that supplies the AMX PC. There are other things apart from Voltage Spikes that can cause these systems huge problems

    YOTPHIX- You wouldn't have to install an ATLAS System just to changeover your generators seamlessly.
  6. yotphix

    yotphix New Member

    Joined:
    Jan 5, 2007
    Messages:
    97
    Location:
    Southern California
    No, you wouldn't, but since most yachts are going to have some kind of shore power system any way, integrating it all kind of makes sense.
  7. TSI AV

    TSI AV Senior Member

    Joined:
    Mar 21, 2006
    Messages:
    104
    Location:
    Estonia
    Hi,

    COMSHIP, Could You be so kind, as to give some more light on a problem ?

    What exactly happens, when You:

    1. Switch 2 generators into paralell work ?
    2. Distribute the load between 2-3 generators ?
    3. Switch off one of generators from paralell work ?

    Normally, even without special seamless system, it's possible to change over from one DG to another, etc. quite smoothly and without "blackout".

    There may be a lot of reasons why voltage / current is unstable (as I understood).

    But I would agree with K1W1 and recommend to use a stabilizer / power filter before electronics and check follow things:

    1. Voltage on busbars of every generator (while idling)
    2. AVRs function.
    3. Reverse power relays.
    4. Synchronizer.
    5. Engine's reaction when getting loaded.

    And I assume, that ATX, electronics are not connected directly to main busbars, ;)

    So, must be a 440/220 V or 380/220 V and then 220/24-12 V traffo after main busbars. The problem can be there as well...

    rgds,

    Andrei
  8. comship

    comship Senior Member

    Joined:
    Jan 27, 2007
    Messages:
    174
    Location:
    Greece
    First of all many thanks to you Guys for your interest to my problem.
    As I said We are currently designing the system but my main fear is that the AMX equipment becomes unstabilized when I was changing source in our previous yacht.

    To answer to your questions:

    1. two generators will not work in parallel. what the Italians normally do is to distribute the load when two generators are running together. To achieve that you have to do it manually.

    2. the generators feature AVR but as I told you the problem is when I change from one source to another

    3. the generators produce 220V 3 phases 50Hz.

    4. The AMX equipment shall be feeded through a UPS

    As you now have a clearer idea how would you plan the system? When you say stabilizer / power filter before electronics you mean a UPS?

    Would the Mastervolt Automatic switch or the Victron be the solution to my problem as per your opinion ?
  9. TSI AV

    TSI AV Senior Member

    Joined:
    Mar 21, 2006
    Messages:
    104
    Location:
    Estonia
    :confused:

    Hi,

    COMSHIP, a couple of questions:

    You mentioned: "two generators will not work in paralell". And then: "distribute the load when two generators are running together".
    What do You mean ?
    1. If I understood You correctly, generators can not work together in parallel
    (together provide voltage on main busbars) ??? But ... Do You have a synchronizer installed ?

    In this case, I recommend to install a synchronizer. Simple one, as a vector type.
    Or even more simple,... 3 bulbs, what will dark at a moment, when 2 sources phases coincide...

    2. What do You mean by "distribute the load" ?
    My understanding: two generators are working in parallel, and by means of decreasing / increasing RPMs it's possible to distribute the load.

    3. When You switch between two sources, do You have a "blackout" or just voltage / current fluctuations?

    rgds,

    Andrei