Sometimes its necessary to not only remember how you engineered a system but to actually document it with placards on the devices so that YOU and anyone else who attempts to operate the equipment learns the necessary procedure.
When designing the dc switchboards I wanted fail safe panels to prevent accidents from wrong switching attempts etc. The first item was the starting batteries. I didn't want them interconnected with any other battery bank - a pure stand alone battery bank dedicated to starting the genset and the main engine. I figured I could always use jumper cables from another battery bank, if it came to that, to get the genset started. Once started the a/c battery chargers would service the other battery banks and I could restore dc charging voltage and hence dc systems operation. In the alternative, I could start the main engine and allow the Balmar external alternator regulators to charge any other battery bank. Near triple redundancy plus the other three banks (house, navigation and engine room) are capable of being parallel interconnected with battery switches.
What I forgot - and did not have placarded clearly was that if I started the main engine from the start battery bank, it was only a matter of time - days - until the start batteries voltage would be depleted below the main engine fuel solenoid holding voltage which when energized opens and allows fuel to the engine. You really don't turn on-off the ignition to a diesel engine - you actually open/close the fuel supply to enable starting or stopping of a diesel engine. Said another way - when the start battery bank reaches 12.1vdc the fuel solenoid starts to close and restricts diesel flowing to the main engine... the engine stalls and comes to a dead stop. Looking at the digital LED voltage panel I should of realized the problem but it did not register (a senior moment?)... had I posted a simple placard - MUST USE ENGINE ROOM OR NAVIGATION BATTERY BANK FOR POWER TO THE MAIN ENGINE FUEL SOLENOID WHEN UNDERWAY TO PREVENT START BATTERY BANK DRAINING.
Some lessons are re-learned again and again in life - until you put checks and balances in place. Take the time next time you learn a lesson to fix it right - complete with a placard to remind ANYONE who is operating the boat - you are not always going to be there.
When I checked the age of the NAV and E/R battery banks, they were six years old. So it seemed like a good time to replace and enjoy the next 5,000nm of voyaging home with new batteries - I had replaced the house bank with new batteries a year earlier. I located a local suppler of LTH batteries - licensed manufacture by Johnson Controls - so now I'm the happy owner of four model 8D LTH wet-cell lead-acid batteries. (best bang for the buck in my opinion). The standing joke is you can tell how good a lead-acid battery is by how much it weights... at 140 pounds each my back says they are real good batteries. Remember it was four old batteries to carry out of the engine room and then four new batteries to carry down into the engine room... oh my aching back, shoulders and neck... this is obvious the biggest problem with 8D batteries - extremely hard to carry and handle. Next time I'm going to 6v golf-cart batteries - I have the 4/0 marine cable and will have the crimper when that time comes... in 5 years?
Now it is time to enjoy a slice of tropical paradise... it is 0800 hours in the morning, January 19th and its 78 degrees fahrenheit in Cancun Mexico.
Norm, how is your winter weather in Indiana? OK, it will be much better in three to four months... about the time I'm home in Oregon preparing to continue north to Alaska... lol
:-)
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Darn it - lost the main engine twice... was able to restart but rather than continue underway towards the pirate infested Mosquito Coast I decided to return to a good port of call - El Cid Marina Mexico, to diagnose and resolve this intermittent problem.
BTW - here are pixs of the Mexican Navy who asked to board and do a "routine" inspection... which involved a detailed "tap" and "peek" for void spaces... guess they think people hide "stuff" when traveling south from the USA to Panama? Oh well... after many hours of waiting they said "OK to go".
Next time, I'm considering saying they have no jurisdiction since we were American Flag in international waters and suggest they call the U.S.State Department for permission or ask the next country, i.e. Panama authorities to do a "routine" boarding upon arrival since we departed Mexico with complete documentation and the Port Captain's Government Authorization to proceed to Panama... undoubtedly the left hand does not know what the right hand is doing... lol
The Mexican ship was the ARM BAJA CALIFORNIA (P162) (Interesting name? Assigned to the Caribbean?) It has a length of 282.2 feet (86.0 m), a draft of 11.8 feet (3.6 m), a beam of 34.4 feet (10.5 m), and displaces 1,850 short tons (1,678.3 t)
Enjoy the pixs... some have not been published since it shows Mexican crew faces which would compromise undercover officer's identities.(Even though they are wearing bandana masks they asked me to not publish them.)
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