LINK 2000 - CAN "LOWBAT" MESSAGE BE WRONG?

[Savanna]

Hi LJH, Opie91 and CharlieJ,

Many thanks for your suggestions and questions, which I will respond to in about 2 weeks time. In the meantime I'm going sailing!

[Savanna]

Hi LJH, Opie91, CharlieJ and Stu Jackson,

Thank you all again for your contributions regarding my Link 2000. While away in the boat I took the opportunity to disassemble the shunt completely and clean it up. It is all nice and shiny now, and the connections are firm and secure.

Stu - Thank you for the link to the "Gotcha Algorithm" - a very interesting article - I learn more all the time.

LJH and CharlieJ - you both asked that I identify the wires coming from the shunt (other than the two twisted pairs). If you refer back to the photo, then the thick red wire coming in from the right comes from the battery bank; the thick red wire departing from the left hand side goes to the distribution board in my "wiring cabinet"; and the thick grey wire departing from the left hand side goes to the windlass. Despite an attempt using torches, unscrewed panels and some contortions, I was unable to discover where the two smaller black wires go. They disappear into a conduit with about 20 other wires (quite a few of which are also black). I would guess (and this is a guess only) that the conduit comes out again somewhere near the distribution board.

Opie91 - You asked what happens when I put a load on the system. A test using my fridge/freezer gave the following results:

Under BAT1 - started with no load. Amp Hours read -4.3. Amps Charged read 0.0. When turned on fridge/freezer this increased to 13.8.

Under BAT2 - started with no load. Amp Hours read +12.6. Amps Charged read 0.2. When turned on fridge/freezer there was no change.

This would suggest to me that something is drawing 0.2 Amps from my non existent BAT2.

Interestingly, with my house bank capacity set at 600 Amp Hours, and the Discharge Floor set at 75%, I would have expected while away sailing that the LOWBAT message should have come on when I had used up 450 Amp Hours. However it came on when I had used about 380 Amp Hours, but as expected it stopped when the batteries were recharged.

Whilst I would be keen to understand what is happening, I can live with managing the problem (I have set the capacity of BAT2 at 1000 Amp Hours, and the Discharge Floor at 100%). So if something obvious comes to mind, I'd be keen to hear about it, but please don't go any great lengths unless it is also of interest to yourselves.

[LJH]

Savanna,

There are a few things that you could do. The black wire (with the yellow crimp) coming off the shunt is supplying what ever your link is recording the 0.2A current flow.
Disconnect it and see what stops working.
You can reconnect it to the bus bar, no current will go through the shunt, or
reconnect it to the shunt and reverse the purple and brown leads on the shunt. This will make the Link thing that BAT2 is charging and will reset BAT to zero.

Originally Posted by Savanna

Hi LJH, Opie91, CharlieJ and Stu Jackson,

Thank you all again for your contributions regarding my Link 2000. While away in the boat I took the opportunity to disassemble the shunt completely and clean it up. It is all nice and shiny now, and the connections are firm and secure.

Stu - Thank you for the link to the "Gotcha Algorithm" - a very interesting article - I learn more all the time.

LJH and CharlieJ - you both asked that I identify the wires coming from the shunt (other than the two twisted pairs). If you refer back to the photo, then the thick red wire coming in from the right comes from the battery bank; the thick red wire departing from the left hand side goes to the distribution board in my "wiring cabinet"; and the thick grey wire departing from the left hand side goes to the windlass. Despite an attempt using torches, unscrewed panels and some contortions, I was unable to discover where the two smaller black wires go. They disappear into a conduit with about 20 other wires (quite a few of which are also black). I would guess (and this is a guess only) that the conduit comes out again somewhere near the distribution board.

Opie91 - You asked what happens when I put a load on the system. A test using my fridge/freezer gave the following results:

Under BAT1 - started with no load. Amp Hours read -4.3. Amps Charged read 0.0. When turned on fridge/freezer this increased to 13.8.

Under BAT2 - started with no load. Amp Hours read +12.6. Amps Charged read 0.2. When turned on fridge/freezer there was no change.

This would suggest to me that something is drawing 0.2 Amps from my non existent BAT2.

Interestingly, with my house bank capacity set at 600 Amp Hours, and the Discharge Floor set at 75%, I would have expected while away sailing that the LOWBAT message should have come on when I had used up 450 Amp Hours. However it came on when I had used about 380 Amp Hours, but as expected it stopped when the batteries were recharged.

Whilst I would be keen to understand what is happening, I can live with managing the problem (I have set the capacity of BAT2 at 1000 Amp Hours, and the Discharge Floor at 100%). So if something obvious comes to mind, I'd be keen to hear about it, but please don't go any great lengths unless it is also of interest to yourselves.

[Opie91]

Savannah,

Like LJH says, you problem is most likely the wire with the yellow crimp on it. Move it to either place illustrated in the picture (if you have not) and see if the problem goes away. Make sure to reset all you amp hour counters.

Good Luck

[Savanna]

Hi LJH and Opie91,
Many thanks for your useful responses, and thank you again for your willingness to share information - much appreciated. I feel I have enough information now to sort out a solution that will work for me. I'm left very curious about the black wire with the yellow crimping, and as and when time allows I will have another attempt to discover what it might be for. Cheers.