1/BOTH/2/OFF Switches Thoughts & Musings

Sep 28, 2008
922
Canadian Sailcraft CS27 Victoria B.C.
As usual great stuff MaineSail!
I have a question that relates primarily to the use of the Echo Charger. I recently purchased a new boat and have customized my wiring on my previous boats to essentially what you have described. I learned from you the need to have all charging sources going to the HB if I were to install the EC. My new boat has a factory installed 1-2-B AND a Start-OFF switch, which the starter is connected to. I don't want to bother with disconnecting this, so my questions:
1) If I run my AO directly to the house bank, do I *need* to remove the jumper from the AO-starter post at the engine? My reasoning for not removing is purely difficulty getting to the starter post;
2) Does the start switch introduce anything that I should be aware of? It simply connects the starter motor to the 1-2-B via a jumper to the C post.
I installed a Reserve battery as soon as I purchased the boat and did not run a leg from my charger to this battery since my two banks are significantly different--House is 2-200AH Wet cells and Reserve is a 95AH AGM, so I don't want the same charging currents going to these via shore power, hence my interest in keeping the Reserve topped up via Echo Charger. If the EC didn't require running the Alt directly to the house I would not bother as I am comfortable with managing my battery usage by keeping my switch to House and switching to Start on that switch, however the EC is the best option in my opinion for keeping the AGM topped up without overcharging. Your feedback would be greatly appreciated!
Solstice

The jumper from the alt to the starter connects to the switch and then the start battery. If you leave the jumper in place the Echo becomes redundant as the alternator output will be connected to both the house bank and the start battery through the switch. It should be removed.
 
Jun 6, 2006
6,990
currently boatless wishing Harrington Harbor North, MD
While this will indeed disable the echo charger, removing the large wire (never heard a wire that size called a jumper BTW) between the alternator and starter will not allow any current to get to the starter. It flows from bat to switch (where you can select which battery is used to power things or both) to the alternator + post to the starter.
 
Sep 28, 2008
922
Canadian Sailcraft CS27 Victoria B.C.
And back from the alt to common on the switch.
Many boats - Catalina, Bayliner among them used this as a charging method. A separate wire from the alt to the switch common is not needed as the "jumper" from alt to starter takes care of it, using the normally heavy starting wire that already exists. I will be removing them on a twin engine Bayliner next week as part of a charging upgrade.

And yes it effectively disables the Echo Charge.
 
May 10, 2008
392
Catalina 355 Boston
Thanks for the feedback--I thought I was missing something and now it makes sense that the echo charger would become redundant--This boat is a Catalina, but although they continue to rely on the large (2/0) cables back to the battery from the start post, they now use dedicated switches for that Starter/Alt run.
I know that MS, Stu are owners/former owners of Catalina's and know the wiring setup well, as do I since this is my third. I am also a member of the C34 group and have read all of the excellent posts there as well....Thanks again...
 
Feb 6, 1998
11,667
Canadian Sailcraft 36T Casco Bay, ME
As usual great stuff MaineSail!
I have a question that relates primarily to the use of the Echo Charger. I recently purchased a new boat and have customized my wiring on my previous boats to essentially what you have described. I learned from you the need to have all charging sources going to the HB if I were to install the EC.
Yes, the Echo Charger is designed to take from the house and feed a start or reserve bank. It is a one way device..


My new boat has a factory installed 1-2-B AND a Start-OFF switch, which the starter is connected to. I don't want to bother with disconnecting this, so my questions:
1) If I run my AO directly to the house bank, do I *need* to remove the jumper from the AO-starter post at the engine?
Yes, leaving it there defeats the purpose of the Echo Charger. This is a short jumper and is not difficult to remove. If you already have access to the back of the alt to run the new house bank wire then it is one more nut to remove.



My reasoning for not removing is purely difficulty getting to the starter post;
You can always disconnect it from the back of the alt, cut the connector off, and seal (this is critical that it be 150% sealed from making contact with anything) the end of the jumper wire and affix/support it to the new wire

2) Does the start switch introduce anything that I should be aware of? It simply connects the starter motor to the 1-2-B via a jumper to the C post.
Without a schematic I can only guess at how they did it. I suspect I know how but won't bet on it..


installed a Reserve battery as soon as I purchased the boat and did not run a leg from my charger to this battery since my two banks are significantly different--House is 2-200AH Wet cells and Reserve is a 95AH AGM, so I don't want the same charging currents going to these via shore power, hence my interest in keeping the Reserve topped up via Echo Charger.
This is one more reason it becomes pretty critical to disconnect the alt jumper wire..

If the EC didn't require running the Alt directly to the house I would not bother as I am comfortable with managing my battery usage by keeping my switch to House and switching to Start on that switch, however the EC is the best option in my opinion for keeping the AGM topped up without overcharging. Your feedback would be greatly appreciated!
If you're comfortable with that then it could work but leaves room for error.. You already own the Echo so might as well use it as it is designed to be used..
 
May 10, 2008
392
Catalina 355 Boston
Thanks again Maine...I thought about cutting the connector and sealing it with rescue tape, but I hate the idea of leaving stray cables, even if I do secure it the new. The problem I have is access to the starter post--alt access is good. However this may be the route I end up taking.
As for the schematic for the wiring of the switches--
2/0 from starter post -->Post 1 on Start switch (2 post switch)
Jumper from C post on start switch to C post on 1-2-B. The 2 switches are about 6" apart.
I have not purchased the EC yet, so technically I do not own it. This is a spring project....with such a mild winter here in New England, I'm starting to line up my project list and this is top of list!
 

BrianW

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Jan 7, 2005
843
Hunter 26 Guntersville Lake, (AL)
Maine.... are you placing your gems of knowledge and info in the "Resources" section of this forum? They are solid gold and should be archived in an easy-to-find library and not only through just a general archives search.
 
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May 10, 2008
392
Catalina 355 Boston
While this will indeed disable the echo charger, removing the large wire (never heard a wire that size called a jumper BTW) between the alternator and starter will not allow any current to get to the starter. It flows from bat to switch (where you can select which battery is used to power things or both) to the alternator + post to the starter.
Bill,
Just re-read your post. I may be misinterpreting what you are saying. The Starter gets current from the battery. The Alt jumper (jumper because it is a short wire that is maybe 12G) goes to the starter and from the starter there is a 2/0g wire that goes to Battery switch, which then connects to batteries. If I select 1, the alt charges the house, 2 the reserve, and Both all banks (hence the need for the EC). Am I missing something?
 
Feb 6, 1998
11,667
Canadian Sailcraft 36T Casco Bay, ME
Bill,
Just re-read your post. I may be misinterpreting what you are saying. The Starter gets current from the battery. The Alt jumper (jumper because it is a short wire that is maybe 12G) goes to the starter and from the starter there is a 2/0g wire that goes to Battery switch, which then connects to batteries. If I select 1, the alt charges the house, 2 the reserve, and Both all banks (hence the need for the EC). Am I missing something?
Ignore it. He thinks your starter is getting fed through the alt jumper.. It's not...
 
Oct 26, 2008
6,045
Catalina 320 Barnegat, NJ
Dual circuit Plus ...

MS, I've been waiting for your commentary regarding this type of switch. I installed this type of switch on my boat a few years ago to replace the old switch, which had a cracked case. I also installed the ACR and a new monitor. Even though I understand the difference between these switches, I don't recognize any difference in the way they would be wired (except for the obvious differences in posts on the switch) or used. In essence, you can have a primary bank and a secondary reserve and the banks would be on separately and charged in the same fashion under normal circumstances. However, the biggest difference that I see is that you can't use the secondary reserve except when combined with the primary (which really is the same as the B switch).

With my switch, I can only think of one reason to use the switch in the combined position and that would be to start the engine in the event of either a discharged house bank (if using the house bank to start the engine) or a discharged start battery (if using a separate start battery). In my case, I have just one battery bank (so my switch is essentially just on and off). I did not wire a separate start battery. In the future, I might add a third battery as a reserve, but my circumstances really don't make this a necessity, currently.

Can you explain any differences you would recommend in setting up the wiring diagram to use DCP in the proper way?

I have really enjoyed this article as well as previous articles on this topic because they have really helped my understanding!
 
Sep 28, 2008
922
Canadian Sailcraft CS27 Victoria B.C.
You have more flexibility with the 1/2/both/off switch than the Dual Circuit Plus switch as you can choose each bank individually and aren't forced to combine. Combining does make sense sometimes - if the ACR or Echo Charge were to fail it allows charging of both banks. Combining a good bank with a discharged bank doesn't make sense.

The 1/2/both/off switch is usually already there so it becomes a less expensive option as well.

I think the DCP switch makes a lot of sense on a small sportfishing or similar boat as it isolates the start battery from the one powering the electronics. I don't think it really belongs on a cruising sailboat though.
 
Feb 26, 2004
22,760
Catalina 34 224 Maple Bay, BC, Canada
However, the biggest difference that I see is that you can't use the secondary reserve except when combined with the primary (which really is the same as the B switch).

With my switch, I can only think of one reason to use the switch in the combined position and that would be to start the engine in the event of either a discharged house bank (if using the house bank to start the engine) or a discharged start battery (if using a separate start battery).


Scott, you really should read the whole thing again. Combining a bad bank and a good one is NEVER a good idea, but it is ALL that the DCP switch will let you do. The 1-2-B switch, never used in B except when charging, allows you to SWITCH banks without combining, i.e., not using B.

You know I have been posting about electrical systems for years, and have included some of Maine Sail's articles in this topic, "Electrical 101"

http://c34.org/bbs/index.php/topic,5977.0.html

Some of those links come right back to this board.
 
Sep 28, 2008
922
Canadian Sailcraft CS27 Victoria B.C.
The 1-2-B switch, never used in B except when charging, allows you to SWITCH banks wityhout combining, i.e., not using B.
And with an ACR or Echo Charge it is not necessary for charging either, except for the very rare exception of a failure of the ACR or Echo.
 
Feb 26, 2004
22,760
Catalina 34 224 Maple Bay, BC, Canada
And with an ACR or Echo Charge it is not necessary for charging either, except for the very rare exception of a failure of the ACR or Echo.
Sorry, I missed repeating that, since MS had already discussed that, which is why I suggested that Scott re-read it all again.

Thanks,

Stu
 
Oct 26, 2008
6,045
Catalina 320 Barnegat, NJ
Primarily, I am asking about the do's and don'ts ...

for configuring and using DCP. Stu, I don't mean to be obstinate, but your comment is vague and condescending. I have read the artlicle and I find little in it to address my specific questions about DCP. It's not that the article is lacking in any way ... MS said at the beginning that he will have more to add in regard to DCP switches. I am certainly interested when he does!

You might be able to point out something in the article that is pertinent rather than pointing out the issues that are clear.

For instance, I never indicated that I think it IS a good idea to set the switch on Combined for any reason other than to start the engine when one of the banks is in a discharged condition.

As far as I can tell, when I turn the DCP switch On, it is no different than when you turn your switch to 1. If I ever turned my switch to Combined, it is no different than your switch if you turned it to B.

I understand that you can use 2 independently from 1, and I also understand that you may be saying that there is NEVER any circumstance where you turn your switch to B.

I am saying that I can only think of one reason to turn my switch to Combined and that would be for an emergency start. It seems to me that to say that is a no-no is a little nit-picky since the B position on your switch does the same thing and MS says that it is a common occurance, even with the 1-2-B switch.

Yes, I have an ACR so I already KNOW that all batteries will charge when I have the switch in the ON position. I didn't have to read the article twice (or even once) to understand ... again, your remarks are condescending.

Stu, I know that you have a bone to pick with DCP switches, but try not to let your attitude cloud your response. If you have nothing to discuss about the ways to properly configure it and use it, then what purpose do you have in responding? If there was a compelling reason for me to switch it out again, it really would be no big deal ... I can afford the few extra bucks. But I still don't see a compelling reason. Mitiempo says that he understands how it is used but doesn't think it belongs on a cruising sailboat, and I respect his opinion. I think I would agree with him if I felt there was a real need for an auxillary bank that is stand alone. So far, most people seem to say that one bank is adequate except for a very infrequent need to start the engine with a charged battery, in which case either the Combined position on DCP or the B position on you switch does the same thing.
 
Feb 6, 1998
11,667
Canadian Sailcraft 36T Casco Bay, ME
MS, I've been waiting for your commentary regarding this type of switch. I installed this DCP type of switch on my boat a few years ago to replace the old switch, which had a cracked case.
Scott,


Pro's of the DCP:

#1 Simplicity - This is a very simple ON/OFF switch with a "BOTH" feature. Does not get any easier.

#2 Isolates Starting Battery - This can prevent equipment "drop out" on boats with small house banks when the house bank previously got used for starting. As the house banks get larger the drop out of equipment is a non-issue. These were originally designed for fishing boats who start and stop the motor multiple times per day to to prevent the fishing instruments from re-setting. These boats very often have equally sized house and starting banks. The switch can work well in this application whether you have a sailboat or power boat with equally sized small banks..

Drawbacks To The Dual Circuit Plus:

#1 The DCP switch lacks the ability to properly isolate a failed bank and take it off line while using the "good bank".

#2 Lacks the ability to use the house bank to power starting and house loads while isolating the "start" bank from the rest of the system.

#3 Lacks the ability to use the starting/reserve battery to power house and starting loads while isolating the "house" bank from the rest of the system.

#4 Lacks the proper instructions for wiring configuration with a large house bank (cruising boats) without re-wiring the alternator output. Connecting it via the factory diagram, to a large house bank, will cause relay cycling. As such the alternator output needs to be re-wired to go direct to the house bank when the banks are unequally proportioned..

Blue Sea offers a technical brief on this here: Prevent Relay Cycling In Battery Combiners

Sadly they don't include this tidbit in the installation instructions so may boaters install them incorrectly for the application.

#5 With a bank failure, such as an internal short, it forces the user to use the "BOTH/COMBINE" feature and combine a good bank with a failed bank. This can leave a boater dead in the water as it did for one of my customers as recently as last summer. That customer has since switched back to a 1/2/BOTH/OFF with a second ON/OFF for engine start isolation. It is more complicated, as he has two switches to turn ON & OFF, but he has more comfort in knowing he has redundancy and full isolation without the need for using the "BOTH/COMBINE" feature, the same feature that left him dead in the water.. While these failures are rare they can & do happen. Short of re-wiring the system, when a battery dies, you have no way to isolate a bad bank.

#6 Most boats already have a perfectly good 1/2/BOTH/OFF switch and the addition of an ACR or Echo Charger will get you the same seamless charging benefit without having to drill more holes in the boat, spend more money or to have less redundancy and isolation.

#7 With the addition of two ON/OFF switches in the battery compartments, not to be seen by vessel occupants, the DCP switch can become quite good because you now have the ability to isolate the bad bank. Create a charge bus on the load side of the hidden house bank switch and you now have a very good solution...


As I have said before for your application the switch will work just fine as it is. Your banks are nearly equally sized. While you do give up the "isolation" and "use choosing" ability, if all goes well you'll be fine and you have no reason to rip it out. For most boaters they work perfectly I just think it is important for everyone to know the pro's and con's of these switches. Blue Sea certainly is not going to tell you these things...

I do install them on center consoles and fishing boats but tend to shy away from them in deep cycling applications such as sailboats..

Hope this helps.. I'm in a rush so I am sure I forgot a few points but these should be the key points.
 
Sep 28, 2008
922
Canadian Sailcraft CS27 Victoria B.C.
For instance, I never indicated that I think it IS a good idea to set the switch on Combined for any reason other than to start the engine when one of the banks is in a discharged condition.

As far as I can tell, when I turn the DCP switch On, it is no different than when you turn your switch to 1. If I ever turned my switch to Combined, it is no different than your switch if you turned it to B.

I understand that you can use 2 independently from 1, and I also understand that you may be saying that there is NEVER any circumstance where you turn your switch to B.

I am saying that I can only think of one reason to turn my switch to Combined and that would be for an emergency start. It seems to me that to say that is a no-no is a little nit-picky since the B position on your switch does the same thing and MS says that it is a common occurance, even with the 1-2-B switch.

Yes, I have an ACR so I already KNOW that all batteries will charge when I have the switch in the ON position.

Stu, I know that you have a bone to pick with DCP switches, but try not to let your attitude cloud your response. If you have nothing to discuss about the ways to properly configure it and use it, then what purpose do you have in responding? If there was a compelling reason for me to switch it out again, it really would be no big deal ... I can afford the few extra bucks. But I still don't see a compelling reason. Mitiempo says that he understands how it is used but doesn't think it belongs on a cruising sailboat, and I respect his opinion. I think I would agree with him if I felt there was a real need for an auxillary bank that is stand alone. So far, most people seem to say that one bank is adequate except for a very infrequent need to start the engine with a charged battery, in which case either the Combined position on DCP or the B position on you switch does the same thing.

Scott

There is never a good idea to combine a good battery with a depleted one. but the DCP gives you that as the only option if the start battery is depleted.

Combine is not the same as B - combine is A + B.

There are circumstances to turn a 1/2/both/off switch to B - when A is depleted. The DCP doesn't give you that option.

That time you switch your DCP into Combine you could end up with 2 banks that will not start the engine - Maine has posted an example of this in the past.

If your ACR is wired properly between the banks both banks will charge with the DCP in any position.

Again the combined position and the B position do 2 different things - combine is Both, B is B alone.

You do not have a B, you have a Both.

Hope this helps clarify.

Now I see Maine was posting as I was.
 
Feb 6, 1998
11,667
Canadian Sailcraft 36T Casco Bay, ME
Scott

There is never a good idea to combine a good battery with a depleted one. but the DCP gives you that as the only option if the start battery is depleted.

Combine is not the same as B - combine is A + B.

There are circumstances to turn a 1/2/both/off switch to B - when A is depleted. The DCP doesn't give you that option.

That time you switch your DCP into Combine you could end up with 2 banks that will not start the engine - Maine has posted an example of this in the past.

If your ACR is wired properly between the banks both banks will charge with the DCP in any position.

Again the combined position and the B position do 2 different things - combine is Both, B is B alone.

You do not have a B, you have a Both.

Hope this helps clarify.

Now I see Maine was posting as I was.
Brian,

The "COMBINE" feature of the DCP does the same thing as the "BOTH" position on a 1/2/BOTH/OFF. It electrically "combines"or parallels both banks. The BOTH feature on a 1/2/BOTH is often used to "direct" the charge where with the DCP kit that is done via the ACR. You CAN use the "COMBINE" feature of the DCP to "charge direct" to BOTH banks if the ACR were to fail..
 
Sep 28, 2008
922
Canadian Sailcraft CS27 Victoria B.C.
Brian,

The "COMBINE" feature of the DCP does the same thing as the "BOTH" position on a 1/2/BOTH/OFF. It electrically "combines"or parallels both banks. The BOTH feature on a 1/2/BOTH is often used to "direct" the charge where with the DCP kit that is done via the ACR. You CAN use the "COMBINE" feature of the DCP to "charge direct" to BOTH banks if the ACR were to fail..
I understand and posted that previously. The failure of the DCP is its lack of a dedicated B position. And both you and I prefer charging not go through any switch on a normal basis, only in case of an ACR or Echo failure.