Link 20 confusion.

[chris_gee]

Aargh. I have two lifeline GPL27T batteries crosslinked in parallel, with a third something separate. There is a link 20, a starter switch thing that says on or off, a combiner switch, and a separate switch that says Bank 1, 2 ,3.

Now looking at the link manual it implies it runs two banks the usual house and start. It also by default assumes 2 x 100 so sets capacity at 200.

However on the panel it refers to battery one and battery 2. No mention of banks. However I assume it means bank by battery.

While having work done various switches appear to have been impacted by big feet leading to two yellow lights suggesting shortage.

Now having put the things on a battery charger I note that when it is on one of the parallel connected house batteries it reads 14.2 volts on battery 1 and 2. That suggests both are getting that charging current, as when charging stops it drops. But since I am not charging the starter bank so far as I know that means battery 1 and battery 2 refer to the house batteries not banks. . So how then would I monitor the other banK?

I found that the capacity was set for bank 1 which drains with the stereo on to 100 amp hrs not 200 and therefore is house?? I also found that the battery type F10 1 = wet 2 =gel was set to one. If the house bank is these batteries ie AMD are they gel or acid or specifically as which are they regarded? I know there is a difference in how the acid is held but given a choice of two which are they? The same choice applies to my battery charger.

I tried resetting the amp hours to 200 but am now getting a flashing red light despite approx 2 hours of motoring at 75 amps and 13 hours on the charger at 8 amps now auto reduced to about 4. Changing back to 100 doesn/t effect this.

I would have thought there were two banks each of which had their charge status shown. albeit as a notional battery. The starter on dial was only connected to the starter bank, unless the all switch was used. However I have found at times if the other 3 way switch is on 2 , the motor won't crank unless I switch to position 1.

I have a suspicion one of the house batteries may be then acting as starter.
In other words maybe there is a dog's breakfast.

Currently all 3 batteries show about 12.4. Would a need to clean all terminals effect things? I found on the delivery trip that all 3 negative terminals were loose.

Okay my physics was a long time ago. I am installing a windlass. Does this go to the starter battery?

I suspect I may need an electrician in - the PO did some of the wiring but before I spend another boat dollar or two maybe on new batteries is anyone with a few clues able to explain this in simple terms? Thanks in advance.

[Omatako]

Chris

Whilst I am no expert, my experience with Link 20 is that it has two shunts that measure current flow. The way they need to be connected is with the negative cable from each bank running to one side of each shunt and the other side of the shunt connecting to the ground bus.

ALL negative feeds from ALL circuits go to the ground bus of the battery they are fed from and NONE to the negative side of the batteries. Then there are a number of other connections that go to the positive sides of the banks, I can't remember them all but the installation instructions are reasaonably clear. If you want I can PM you the said manual.

What is important about the first paragraph is that any device that leads back to the battery negative will not be "seen" by the Link20. So in short, only one cable must be connected to the neg side of the banks, that is the fat battery cable that runs to the Link shunt.

My 1-all-2 switch only controls the charge to the banks and the postive feeds to the appliances. The Link does not differentiate where this switch is set. You can pretty much set this switch up as you choose. Mine is set up with the whole house bank on 1 and the other bank on 2 but you can split your house bank into two if you can find a valid reason to want to

Also, Link20 allows you to set the size of your banks in terms of amp hours and the Link will better be able to calculate the remaining capacity. You can also reset the amp hours to zero any time you choose and start the consumption calcs from base. These settings are also clearly descrbed in the manual.

Hope this is of some value although your description above does sound a little like a can of worms.

[camaraderie]

Follow the very thin little wires that run from the back of the link to find out what they are measuring. The wires are color coded and identified in your manual.
What Andre says about onle ONE negative wire being attached to your bank and THAT wire being run to one side of your shunt #1 and ditto for shunt #2 is critical.
It is unclear from your post just how your battery switch and charger are wired in. All you can do once you are sure the link is wired right is to run various loads and see which bank they register on. As you guessed "battery 1" means battery BANK #1...not individual batteries unless you only have one battery in a bank.

You have nowhere near enough battery capacity to run a windlass in my judgement. You should add capacity. You do NOT need to have your starter battery as one of your two banks on the Link. Use one deep cycle bank as your windlass battery and the other as your house batteries on the Link.

As to the 12.4V reading...if this is being taken at rest after full charging at the dock AND with no loads on the batteries...you have a serious degradation of capacity and you batteries are nearly shot. To be sure...clean everything up...charge overnight and then turn everything off of a few hours. Then take volt readings AT each battery terminal with a voltmeter.

By the way...default on the link is 200ah's capacity which is exactly what you have in your bank. The F1 setting for wet cells is correct as only GEL takes a different link setting.

[chris_gee]

Thanks sorted it out more or less. The external charger on the battery did not register on the link 20 but went through a smart charger thingy which applied the charge to all batteries so the starter bank showed up at charging v.
I havent yet done a full floating charge = the marina is not liveaboard so effectively it is day time only but it looks like I won't need new batteries just yet.
The winch only draws 30-40 amps so with the motor running I am told should be fine on the starter battery. At this stage I don't have refrigeration so the bank while small will probably do in the meantime.
Some maintenance panel may be a good idea though.