[C320-list] Battery Isolation

[Robert Seastream]

What does the newer code specify in lieu of wing nuts?  Wraparound  
clamps such as used on (older) automobile batteries with lead posts?
On Apr 23, 2009, at 6:15 PM, Kirk McCullough wrote:

> Warren
>
> The only thing the surveyor noted in his report regarding the DC  
> systems
> were the wing nuts used on the battery posts. Wing nuts are no longer
> acceptable under the newer code. He was happy with the rest  
> including the
> wiring of the house and starter banks.
>
> I don't mind the brain exercise I get when deciding on which bank to
> charge.... should I do the house bank or maybe I should do the  
> starting
> bank? The link 20 system tells me the state of each and simplifies the
> decision, although as I mentioned below, the starting battery is  
> normally
> fully charged, since it gets little use.
>
> The only other thing that taxes my mind to these levels is when to  
> get into
> the dinghy and check the crab pots. :)
>
> Kirk
> #124
>
>
> -----Original Message-----
> From: c320-list-bounces at lists.catalina320.com
> [mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of warren  
> updike
> Sent: 22 April 2009 14:40
> To: C320-List at Catalina320.com
> Subject: Re: [C320-list] Battery Isolation
>
>
> I believe one of the recommended approaches cited on the C320 web  
> site is
> just exactly that: to connect the starting bank on 2, and the house  
> bank on
> 1. I can't imagine a surveyor having an issue with any such approach  
> as long
> as the proper sized wires are used, solid connections, conduit,  
> fusing, etc.
>
>
> The difference is merely one of ease and convenience. With my dual  
> circuit
> switch my power is either on or off. Shore charger and alternator  
> charge the
> house bank and the combiner manages the starting bank.  I don't ever  
> think
> about it. Turn it on when I arrive. Turn it off when I leave. No  
> thinking
> about whether to switch between 1 or 2 or Both as I transition from  
> power to
> sail to dockside.  On or Off. I can handle that.
>
> Incidentally, I also installed a battery monitor. Acts like a fuel  
> gage to
> let me know how much capacity remains in the house bank and sounds  
> an alarm
> should it get too low. It's a very sophisticated device; but, it  
> simplifies
> the power management. It's either at 100%, 50% or somewhere in  
> between.
>
> I don't like to think too much when I'm having fun. On or Off. No  
> thought.
>
> Warren & Pattie Updike
> Catalina 320, #62, "Warr De Mar"
> Middle River, Chesapeake Bay
>
>
>
> -----Original Message-----
> From: Jeff Church [mailto:jc387 at att.net]
> Sent: Tuesday, April 21, 2009 4:00 PM
> To: C320-List at Catalina320.com
> Subject: Re: [C320-list] Battery Isolation
>
> Kirk,
>
> I'm not sure. I'd have to ask that picky surveyor.
>
> I guess the question arises in my mind because everyone I asked
> suggested that I use either a combiner or isolator. No one even hinted
> that I should just use the switch to control charging. I'm not saying
> that your solution is wrong, I just wonder what the "experts" or a
> surveyor would have to say about it.
>
> JeffC
>
>
> Kirk McCullough wrote:
>> Jeff
>>
>> I just had a survey in February for insurance reasons. The surveyor
> checked
>> out all electrics mainly from a safety angle and gave me a clean  
>> report.
>>
>> What would be the concern with this arrangement?
>>
>> Kirk
>> #124
>>
>> -----Original Message-----
>> From: c320-list-bounces at lists.catalina320.com
>> [mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Jeff  
>> Church
>> Sent: 18 April 2009 18:41
>> To: C320-List at Catalina320.com
>> Subject: Re: [C320-list] Battery Isolation
>>
>>
>> Kirk,
>>
>> Catalina installs the optional starting battery that way on the 387.
>> They just parallel the house batteries and connect the starting  
>> battery
>> to #2 on the battery switch,  without using an isolator or  
>> combiner. I'm
>> not sure what a picky surveyor would say about that.
>>
>> JeffC
>>
>>
>> Kirk McCullough wrote:
>>
>>> Is it not just about as easy to leave the house and starting  
>>> batteries
>>> un-combined or un-isolated and just select which one to charge with
>>> the 1-2-both switch? That's what I do and the starting battery is
>>> always good to go. I don't use it for anything but starting and even
>>> then if I happen to be on house while at anchor I often just use  
>>> them
>>> to start the engine.
>>>
>>> I didn't see or maybe didn't properly understand the benefit of the
>>> ACR when it was explained to me recently, so I just bought a new  
>>> Blue
>>> Sea 1-2-Both switch when I bought new 4D deep cycle batteries last
>>> fall, just to be sure I wasn't getting any leakage across my old
>>> original Guest 1-2-Both I replaced it. All is good.
>>>
>>> Kirk
>>> #124
>>>
>>> ----- Original Message ----- From: "Jeff Church" <jc387 at att.net>
>>> To: <C320-List at Catalina320.com>
>>> Sent: Friday, April 17, 2009 7:35 PM
>>> Subject: Re: [C320-list] Battery Isolation
>>>
>>>
>>>
>>>> Bob,
>>>>
>>>> Me too. That's why I thought as soon as the combiner closes,  
>>>> current
>>>> from both the charger and starting battery would flow through the
>>>> house batteries until the resistance of the house bank increased.
>>>>
>>>> What would happen if there was a shorted cell in the house bank?  
>>>> With
>>>> a combiner couldn't the starting battery discharge thru the shorted
>>>> house battery?
>>>>
>>>> I was also told by the guys at Charles that since the discharged
>>>> house batteries present the least resistance, most of the bulk and
>>>> absorption charge will flow thru them, so the smaller starting
>>>> battery will not over charge.
>>>>
>>>> Jeff
>>>>
>>>>
>>>> Robert Seastream wrote:
>>>>
>>>>> I thought a discharged battery has an extremely low resistance,  
>>>>> thus
>>>>> presenting a near short to any charging source.
>>>>>
>>>>> Bob Seastream
>>>>>
>>>>>
>>>>> On Apr 17, 2009, at 10:00 AM, <crashley at gte.net> wrote:
>>>>>
>>>>>
>>>>>> At the risk of offending Orlando again, I'll take a crack at  
>>>>>> this.
>>>>>> When you
>>>>>> turn the charger on into an open circuited or discharged house
>>>>>> battery, it
>>>>>> takes a little while (several seconds) for the battery voltage to
>>>>>> climb up
>>>>>> to the initial charging voltage which should be about 14.4V. This
>>>>>> delay is
>>>>>> because the battery looks like a large capacitor. The ACR has a
>>>>>> time delay
>>>>>> in it so when it senses that the house battery voltage is 13.5V  
>>>>>> (or
>>>>>> higher)
>>>>>> the timer starts and 30 seconds or so later the relay closes. At
>>>>>> this point
>>>>>> the house battery is at 14.4V and the starting battery is at  
>>>>>> 12.7V
>>>>>> (open
>>>>>> circuit voltage) so it will start charging too. I think the only
>>>>>> possible
>>>>>> issue here is that if the house battery is a lot larger than the
>>>>>> starter
>>>>>> battery, which is normally the case, the starter battery will  
>>>>>> see a
>>>>>> longer
>>>>>> "absorb" charge time than it needs, but I don't think this is a  
>>>>>> big
>>>>>> problem.
>>>>>>
>>>>>> Long live space junk!
>>>>>>
>>>>>> CR Ashley
>>>>>> Rosebud C320 Hull #882
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> -----Original Message-----
>>>>>> From: c320-list-bounces at lists.catalina320.com
>>>>>> [mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of  
>>>>>> Jeff
>>>>>> Church
>>>>>> Sent: Wednesday, April 15, 2009 10:57 AM
>>>>>> To: C320-List at Catalina320.com
>>>>>> Subject: Re: [C320-list] Battery Isolation
>>>>>>
>>>>>> Chris,
>>>>>>
>>>>>> Like I said, maybe I didn't totally understand what the guys at
>>>>>> Charles and
>>>>>> PS (2 independent sources) told me.
>>>>>>
>>>>>> Why wouldn't the ACR sense 14 volts, or more, the moment that the
>>>>>> charger
>>>>>> switches on? My battery monitor does. I know that there will be
>>>>>> some voltage
>>>>>> drop due to the discharged house, but the charger output is
>>>>>> 15 or 16 volts initially.
>>>>>> .
>>>>>> Jeff
>>>>>>
>>>>>>
>>>>>>
>>>>>> crashley at gte.net wrote:
>>>>>>
>>>>>>> I disagree. It doesn't surprise me that the guys who make the
>>>>>>> expensive MOSFET devices will tell you what they did. The ACR  
>>>>>>> will
>>>>>>> not
>>>>>>> close until the battery being charged reaches 13.5V. The starter
>>>>>>> battery should be sitting at around 12.7V before that so it  
>>>>>>> will not
>>>>>>> discharge into the higher voltage battery, it will actually  
>>>>>>> start
>>>>>>> receiving charge current as well. I agree that the ACR will  
>>>>>>> allow
>>>>>>> current to go in either direction, but in this case it should  
>>>>>>> not.
>>>>>>> The
>>>>>>> only time this might occur is if the charging source goes away  
>>>>>>> in
>>>>>>> which case the ACR will open when the house battery drops to
>>>>>>> 12.7V, so
>>>>>>> it should not allow the starter battery to discharge too much  
>>>>>>> into
>>>>>>> the
>>>>>>>
>>>>>> house battery since 12.7V is a fully charged state for lead acid
>>>>>> batteries.
>>>>>>
>>>>>>> PS: I am an EE and have been designing battery chargers and
>>>>>>> dischargers for spacecraft for 28 years. Talk about $$$$!
>>>>>>>
>>>>>>> CR Ashley
>>>>>>> Rosebud C320 Hull #882
>>>>>>>
>>>>>>>
>>>>>>> -----Original Message-----
>>>>>>> From: c320-list-bounces at lists.catalina320.com
>>>>>>> [mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of  
>>>>>>> Jeff
>>>>>>> Church
>>>>>>> Sent: Tuesday, April 14, 2009 10:53 PM
>>>>>>> To: C320-List at Catalina320.com
>>>>>>> Subject: Re: [C320-list] Battery Isolation
>>>>>>>
>>>>>>> When I was designing my setup I spoke at length to several  
>>>>>>> engineers.
>>>>>>> The techs at Charles and Perfect Switch (PS makes MOSFET  
>>>>>>> isolators
>>>>>>> ($$$$) for the military and NASA) told me about this particular
>>>>>>> problem.
>>>>>>>
>>>>>>> My understanding is that when the charger comes ON, the ACR  
>>>>>>> senses
>>>>>>> the
>>>>>>> voltage and the switch closes. At that point current flows  
>>>>>>> from any
>>>>>>> available source towards the path of least resistance. In this  
>>>>>>> case
>>>>>>> the house batteries are the path of least resistance and  
>>>>>>> current will
>>>>>>> flow from both the charger and the starting battery to the house
>>>>>>> batteries until the resistance in the house and starting  
>>>>>>> batteries
>>>>>>>
>>>>>> equalizes.
>>>>>>
>>>>>>> An isolator does not allow any current to pass from one  
>>>>>>> battery bank
>>>>>>> to the other.
>>>>>>>
>>>>>>> I'm not an EE so maybe I got it wrong.
>>>>>>>
>>>>>>> JeffC
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> crashley at gte.net wrote:
>>>>>>>
>>>>>>>
>>>>>>>> JeffC,
>>>>>>>>
>>>>>>>> The Blue Sea Systems battery combiner relay (ACR 7600) has a  
>>>>>>>> voltage
>>>>>>>> sensor so it will not close until the house battery is being  
>>>>>>>> charged
>>>>>>>> at 13.5V so the starter battery should never discharge into the
>>>>>>>> house
>>>>>>>>
>>>>>>>>
>>>>>>> battery.
>>>>>>>
>>>>>>>
>>>>>>>> CR Ashley
>>>>>>>> Rosebud C320 Hull #882
>>>>>>>>
>>>>>>>>
>>>>>>>> -----Original Message-----
>>>>>>>> From: c320-list-bounces at lists.catalina320.com
>>>>>>>> [mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of  
>>>>>>>> Jeff
>>>>>>>> Church
>>>>>>>> Sent: Wednesday, April 08, 2009 5:59 PM
>>>>>>>> To: C320-List at Catalina320.com
>>>>>>>> Subject: Re: [C320-list] Battery Isolation
>>>>>>>>
>>>>>>>> Good info. I looked all over for a Schottky diode isolator and
>>>>>>>> didn't
>>>>>>>> find out that Guest made one. It also didn't occur to me that
>>>>>>>> relay-type devices could create RF noise. I just found the  
>>>>>>>> Guest
>>>>>>>> unit
>>>>>>>> (#2530) at Pyacht.com for about $140.
>>>>>>>>
>>>>>>>> I recently installed a Sure Power Schottky-diode isolator  
>>>>>>>> when I
>>>>>>>> installed a starting battery on my 387. According to several
>>>>>>>> sources,
>>>>>>>> using an isolator is a better approach than using any of the
>>>>>>>> combiners or other relay-type devices. The biggest problem  
>>>>>>>> with a
>>>>>>>> combiner/relay is that when the charging device initially  
>>>>>>>> starts and
>>>>>>>> the combiner closes, the depleted house bank can immediately  
>>>>>>>> draw a
>>>>>>>> lot of current from the  starting battery. Some of the  
>>>>>>>> devices like
>>>>>>>> the Echo Charger might not operate that way, but you should  
>>>>>>>> check on
>>>>>>>> that before buying one. The advantage of the combiner is that  
>>>>>>>> it is
>>>>>>>> easier to install and
>>>>>>>>
>>>>>>>>
>>>>>>> less wire ($$) is required.
>>>>>>>
>>>>>>>
>>>>>>>> In order to install an isolator you will need to remove the  
>>>>>>>> wire
>>>>>>>> that
>>>>>>>> connects the alternator to the starter motor, and run a #6  
>>>>>>>> wire from
>>>>>>>> the alternator to the input terminal on the isolator. Then  
>>>>>>>> from the
>>>>>>>> #1 and
>>>>>>>> #2 output terminals on the isolator you run wires to the  
>>>>>>>> battery
>>>>>>>> switch
>>>>>>>> #1 and #2 terminals, or directly to the house and starting
>>>>>>>> batteries.
>>>>>>>>
>>>>>>>> Good luck.
>>>>>>>>
>>>>>>>> JeffC
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> jelliott at landspring.net wrote:
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>> I'm learning more... These are relay-based devices; Blue Sea  
>>>>>>>>> tech
>>>>>>>>> support says they may induce RF noise if installed at the  
>>>>>>>>> panel vs.
>>>>>>>>> at the battery (not desirable in my case).  Have you  
>>>>>>>>> experienced
>>>>>>>>> this?
>>>>>>>>>
>>>>>>>>> The Guest isolators use Schottkey diodes, which induce a  
>>>>>>>>> load (and
>>>>>>>>> corresponding heat), but don't suffer the potential RF  
>>>>>>>>> problem.
>>>>>>>>>
>>>>>>>>> As usual, there is a tradeoff...
>>>>>>>>>
>>>>>>>>> Julian
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>> The Yandina is the one I used (mine is a WM re-label of this
>>>>>>>>>> product.) It's as simple as described. The Blue Seas Relay  
>>>>>>>>>> will
>>>>>>>>>> definitely do the trick as well...
>>>>>>>>>>
>>>>>>>>>> Regards,
>>>>>>>>>>
>>>>>>>>>> Jon Vez
>>>>>>>>>> Solstice #582
>>>>>>>>>>
>>>>>>>>>> -----Original Message-----
>>>>>>>>>> From: c320-list-bounces at lists.catalina320.com
>>>>>>>>>> [mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of
>>>>>>>>>> jelliott at landspring.net
>>>>>>>>>> Sent: Wednesday, April 08, 2009 4:09 PM
>>>>>>>>>> To: C320-List at Catalina320.com
>>>>>>>>>> Subject: Re: [C320-list] Battery Isolation
>>>>>>>>>>
>>>>>>>>>> John,
>>>>>>>>>>
>>>>>>>>>> I see WM has a Blue Sea Systems Starting Isolation Charging  
>>>>>>>>>> Relay
>>>>>>>>>> which seems to do the trick.  Is that what you installed?
>>>>>>>>>>
>>>>>>>>>> Also seen similar items from Guest and from a company called
>>>>>>>>>> Yandina (http://www.yandina.com/NewCatalog.htm).
>>>>>>>>>>
>>>>>>>>>> Looks like this fits the bill with a fairly straightforward
>>>>>>>>>>
>>>>>>>>>>
>>>>>>> installation.
>>>>>>>
>>>>>>>
>>>>>>>>>> Almost too simple to be real...
>>>>>>>>>>
>>>>>>>>>> Julian
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>> Julian,
>>>>>>>>>>>
>>>>>>>>>>> I have the exact setup you describe. I used a battery  
>>>>>>>>>>> combiner
>>>>>>>>>>> from West Marine. It's a simple device that you simply  
>>>>>>>>>>> wire to
>>>>>>>>>>> each pole on the back of your current switch--one wire to  
>>>>>>>>>>> the '1'
>>>>>>>>>>> and the other to the '2'.
>>>>>>>>>>> It's
>>>>>>>>>>> about the size of a match box and takes a couple of  
>>>>>>>>>>> minutes to
>>>>>>>>>>>
>>>>>> install.
>>>>>>
>>>>>>>>>>> It
>>>>>>>>>>> will combine the batteries when motoring via the  
>>>>>>>>>>> alternator and
>>>>>>>>>>> isolate them when not receiving a charge. Is the 'easy'  
>>>>>>>>>>> solution
>>>>>>>>>>> to this problem....
>>>>>>>>>>>
>>>>>>>>>>> Regards,
>>>>>>>>>>>
>>>>>>>>>>> Jon Vez
>>>>>>>>>>> Solstice #582
>>>>>>>>>>>
>>>>>>>>>>> -----Original Message-----
>>>>>>>>>>> From: c320-list-bounces at lists.catalina320.com
>>>>>>>>>>> [mailto:c320-list-bounces at lists.catalina320.com] On Behalf  
>>>>>>>>>>> Of
>>>>>>>>>>> jelliott at landspring.net
>>>>>>>>>>> Sent: Wednesday, April 08, 2009 10:59 AM
>>>>>>>>>>> To: C320-List at catalina320.com
>>>>>>>>>>> Subject: [C320-list] Battery Isolation
>>>>>>>>>>>
>>>>>>>>>>> I am in the process of modifying my electrical system, and  
>>>>>>>>>>> am
>>>>>>>>>>> curious as to how others electrically isolate the house  
>>>>>>>>>>> bank from
>>>>>>>>>>> the starting battery.
>>>>>>>>>>>
>>>>>>>>>>> I have two 4D's under the settee paralleled as my house  
>>>>>>>>>>> bank, and
>>>>>>>>>>> a separate  starting battery located in the port lazarrette.
>>>>>>>>>>> Both are
>>>>>>>>>>> connected to independent channels of a Xantrax Truecharge
>>>>>>>>>>> 20.   The
>>>>>>>>>>> house
>>>>>>>>>>> bank is monitored with a Link 10.
>>>>>>>>>>>
>>>>>>>>>>> The banks are still not electrically isolated; I assume  
>>>>>>>>>>> this is a
>>>>>>>>>>> result of a common connection to the alternator?  How do  
>>>>>>>>>>> others
>>>>>>>>>>> handled
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>> this?
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>>>> I
>>>>>>>>>>> understand there are battery isolators that do this?  Any  
>>>>>>>>>>> advice
>>>>>>>>>>> on how to "break" this return circuit (if that's the  
>>>>>>>>>>> cause) would
>>>>>>>>>>> be appreciated.
>>>>>>>>>>> I
>>>>>>>>>>> am not very interested in adding a second switch which I  
>>>>>>>>>>> know
>>>>>>>>>>> some
>>>>>>>>>>> have done.
>>>>>>>>>>>
>>>>>>>>>>> Thanks,
>>>>>>>>>>>
>>>>>>>>>>> Julian
>>>>>>>>>>> Polaris #340
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>
>>
>>
>>
>
>