110v charging system (task)

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The original battery charger aboard in 2007 has been removed (Jul08).
This task, and associated test plan for the "blue wire" control wire, are associated with this original Raritan charger.
The writeup below is being struck thru -- but not deleted -- in case we want to use the old unit awhile longer.

NOTE: See 120-V AC Battery Charger entry in the Systems List for high-level writeup of the charger [ThomS quick study c.Sep07]

Under the port side bench in the main cabin (forward of the nav station, aft of the freshwater tank) is a unit that appears to be a battery charger for when the boat is hooked to shore power.

Ted disconnected it from the 12v system when he repaired the alternator. [Specifically, the circuit within the 110V charger (converter) unit that inhibits it from charging the batteries while the engine is running has been disconnected at the engine end -- i.e., the "blue-wire" signal wire that tells the converter that the engine is running, hence expecting to be being charged by the engine's alternator. Note that the connections which carry the charging current from the converter to the three batteries were never removed.]

Someone needs to:

  1. look through the manual to see how it works
    1. DONE: reported in 120-V AC Battery Charger|Systems list
    2. TODO: another person should review this c.Oct07-Feb08 work in this section.
  2. verify how it should be connected to the 12v system
    1. DONE: see above reference. It (the "blue wire") connects to the down-stream side of the fuel-pressure switch (see item 11's right-side contactor in the Engine_schematic_dgm.)
  3. verify that it is properly connected to the 110v system (i.e., the charging function, NOT the "blue-wire" charge inhibiting function.
    1. DONE: I.e., the 110v -to- 12v charging circuit works [Ship's log c. Nov07-Jan08 TODO: find dates]
    2. DONE: Continuity check between all 3 shore power wires and ship's ground (i.e. stern pulpit) shows OPEN (no connection) with ohmmeter
  4. TODO: test the "blue-wire" charging inhibition circuit:
    1. connect shore power and charge the batteries with the converter
    2. momentarily connect the "blue wire" at the engine end to any 12V "+" source
    3. observe (we expect) that the converter desists charging of the batteries; note that by a drop in voltage from c. 13.x volts to 12.x volts at the terminals of the OFF battery.
    4. TODO: now we can permanently re-connect the "blue wire" charge-inhibition signal as mentioned above
    5. power it up to see that it works
      1. hook up shore power, turn on the inverter, and observe batteries charging, especially leave one battery OFF at the main battery switch but see that it is indeed charging.
      2. start the engine, and observe that the battery that is NOT turned ON isn't being charged any more; i.e., we assume that if this battery isn't being charged by the 110v inverter, then even the batteries which ARE still being charged are being charged only by the engine.
    6. if above steps seem to work, re-connect it to the 12v system at the engine-running point.
    7. verify that the 110V converter charges the batteries properly, and inhibits charging when engine is running (can use the one-battery-OFF test above)
  5. document how to use it (the 110V shore power charging subsystem) for future reference.

NOTE: See [12-V Schem walk-thru sect 4] for description of connection to 12-V DC battery circuits for charging. The discussion there, along with the 12-V primary power schematic, answer to the "look thru the manual" and "verify how it should be connected" action items above.

NOTE: in Jul08 the original battery charger (converter) and its wiring were removed; a new system is planned, to be usable with newer 12-volt battery technologies; see Matt's new "replace batteries and battery wiring" to-do item in Outstanding Tasks section above.

TODO: write up operator steps for normal use (after new (>Jul08) battery & charger system installed