Battery Isolators,Separators, and Switches?

[Scalf77]

OK, I have not actually tried this yet. If had a Blue Sea 7620 or 22 I could try it out. But I believe this modification will make the 7622 unidirectional. I know many members here really like the bidirectional feature, but I like you do not. I use a traditional relay that will turn on when the van is running and thus disconnect the 12 volts that I have attached to the NC side of the relay, to the two start isolation circuits. According to the Blue Sea documentation two of the start isolation circuits tied to 12 volts will isolate the batteries. This way, when you are not driving the it will be in isolation mode.

Like I said I have not tested this, and I don't know if the switch will be able to override the isolation so that could be a drawback. Even so a simple switch could be added before the relay and you could go back full Bidirectional mode.



A second way would using the same idea but having the output of the switch go through the relay. In this case the switch would have to set to the off position. When the van was running the relay would pick the NO contact and put the 7622 into auto mode. When the van was not running the switch would work as normal, so having it off would isolate the batteries.



Not sure if any of these two methods interest you.
I think if I was going to do it I would use the second one.
-greg

[coyotearms]

That's a lot of food for such a quick replay! If I understand what you are thinking by the 2nd diagram is to use the manual switch in its auto position to act as it usually does when the engine is running and act like it's in the disconnect position when the engine if off, correct? I cannot tell right off because I don't know the functional diagrams for either the relay or the manual switch.

But after thinking about what you are proposing and looking at the manual again, what about something simple that puts one of an ISOLATION leads positive when the engine is off? One way would be with a small relay that connects an ISOLATION lead to house 12V only when the engine is running. What do you think? I haven't thought through how the manual switch would work or how jumping for emergency starting would work, again because I don't know how the manual switch functions, but wanted to throw that out to you.

[Scalf77]

Ok, I changed it a bit and added a few details for clarity, also 7622 or 7620 will be interchangeable.

First I removed the 6007 Manual Blue Sea Switch, to simplify the whole thing and I added a switch to the Van Run Circuit (switch 1) that I should have put in previously.

Switch 1 SPST enables van run circuit to control SPDT relay #2 (85).

In normal applications the Blue Sea Switch PN2146 (on -off -on), would be in the middle position and the 7622 would monitor the voltage and connect the batteries accordingly. The off position of the switch would disconnect the 7622, while the on position would connect the 7622.

SPDT Relay #2 controls the output of the Blue Sea SPDT switch, when Relay #2 is active (Van Running). ( 87 -Normally Open) puts an open value to the output of relay#2 (30). This would be equivalent to the Blue Sea SPDT Switch being in the (middle) position putting the 7622 in Auto-mode. The position of the Blue Sea SPDT switch will be irrelevant, as it essentially disabled, the LED indicator will still work.

When Relay #2 is not active (Van Off – or Switch#1 Off) ,the (87a -Normally Closed) input or the output of the Blue Sea SPDT Switch to the relay#2 (30) output. This makes the Blue Sea SPDT switch fully functional. If the Blue Sea Switch is left in the off position, when the van is not running it would forced the 7622 off.

Note: if you don't want to wire in the Blue Sea SPDT PN2146 switch then I would wire a ground wire to (87a -Normally Closed) input of the relay.

So when the van is running you get the full features of the Voltage Monitoring capabilities of the Blue Sea 7622 ML-ACR. It will cost you the power turning on relay #2.

If you wanted to add the Blue Sea 6007 switch back in, the switch has four position

Off- Neither circuit 1 or 2 are connected
1- Circuit 1 is connected (or the Blue Sea 7622 is being used)
2- Circuit 2 is connected (manually connecting the batteries together)
Combined - Both circuit 1 & 2 are active


I hope this helps make it a little clearer, although I have not had my second cup of coffee yet. I believe this is better then using the isolation connections.

-greg

[1der]

Just want to check in on something I am wanting to do and get input on its merits and pitfalls.

Is there another downside, other than forgetting to select the right position when camping, to using just a Batt 1 / Batt 2 / Both barrel switch like I had in my boat? If that is the only downside, then I am willing to live that since there is nothing more "encouraging" then being 50 miles from port in a remote anchorage and not being able to start the engines!

For our van set-up, I would like to have two frame mounted batteries for the house running off the stock 135 A ?? v10 alternator plus a circuit to allow external charging (generator, battery charger, solar, etc) of the house battery bank when stationary. I already have a 1500w inverter currently running off the starter battery and would switch this and its loads (currently refer, computer, future mwave, some led lights) over to the house bank.

If the house batteries are AGM and starter is lead acid, how to do I make sure to get proper charging profile each bank? Or is better to go with sealed lead acid all around?

Thanks for any input

[coyotearms]

Originally Posted by Scalf77

SPDT Relay #2 controls the output of the Blue Sea SPDT switch, when Relay #2 is active (Van Running). ( 87 -Normally Open) puts an open value to the output of relay#2 (30). This would be equivalent to the Blue Sea SPDT Switch being in the (middle) position putting the 7622 in Auto-mode. The position of the Blue Sea SPDT switch will be irrelevant, as it essentially disabled, the LED indicator will still work.

So when the van is running you get the full features of the Voltage Monitoring capabilities of the Blue Sea 7622 ML-ACR. It will cost you the power turning on relay #2.



-greg

Yes, just knowing your relay #2 is a normally closed 87a-30 connection that opens when the engine is running makes your plan clear. And I am assuming you only mentioned 87 to just clarify that 87-30 are connected when engine is of, but since 87 is not connected to anything, it really doesn't matter. So to summarize what I think your circuit does: 1) when the engine is running a) the Blue Sea control switch position has no effect and b) both battery banks are connected and both the alternator and solar both have the ability to charge both battery banks and 2) when the engine is off a) the Blue Sea control functions normally and b) therefore if left in the middle position, the 7622 is bi-directional again.

That last observation means if one wants all solar to go to house when camped, the Blue Sea control switch has to be moved to the batteries disconnected position (down), and before driving one has to remember to turn it back to normal. That would not be entirely bad since there are nice sunny days when one is sure whacking both banks will charge both before the sun goes down, but on questionable days that would not be the case.

[quote="Scalf77"]
Note: if you don't want to wire in the Blue Sea SPDT PN2146 switch then I would wire a ground wire to (87a -Normally Closed) input of the relay.[\quote]

I am afraid I don't understand what this means. If SPDT PN2146 is relay #2, 87a is part of it. Do you mean SPDT PN1246 is the Blue Sea 6007?

If you would like to, we could PM each other until we figure this out (maybe after you respond to this post so other folks don't get entirely confused by my response)? Your choice.

-Fred

[daveb]

Originally Posted by 1der

Just want to check in on something I am wanting to do and get input on its merits and pitfalls.

Is there another downside, other than forgetting to select the right position when camping, to using just a Batt 1 / Batt 2 / Both barrel switch like I had in my boat? If that is the only downside, then I am willing to live that since there is nothing more "encouraging" then being 50 miles from port in a remote anchorage and not being able to start the engines!

For our van set-up, I would like to have two frame mounted batteries for the house running off the stock 135 A ?? v10 alternator plus a circuit to allow external charging (generator, battery charger, solar, etc) of the house battery bank when stationary. I already have a 1500w inverter currently running off the starter battery and would switch this and its loads (currently refer, computer, future mwave, some led lights) over to the house bank.

If the house batteries are AGM and starter is lead acid, how to do I make sure to get proper charging profile each bank? Or is better to go with sealed lead acid all around?

Thanks for any input

A manual switch is fine and used by many boaters and RVers. It also takes out any complexity that could create more field issues. But I still haven't had any problems with charging whether shore or even solar in limited light using the 7622. Automatic is the key reason I think its better. In my case I would leave the switch in the wrong position and end up with low or dead batteries using a manual switch.
I did replace my starting batteries with AGM's because IMO standard wet cell auto batteries were having an issue with the day to day solar charging.

[Scalf77]

Yes, just knowing your relay #2 is a normally closed 87a-30 connection that opens when the engine is running makes your plan clear. And I am assuming you only mentioned 87 to just clarify that 87-30 are connected when engine is of, but since 87 is not connected to anything,

I mention 87, only because when the relay becomes active, it becomes closed, which you are correct has nothing on the input, so it would default the 7622 to be in auto mode or Bidirectional.

it really doesn't matter. So to summarize what I think your circuit does: 1) when the engine is running a) the Blue Sea control switch position has no effect and b) both battery banks are connected and both the alternator and solar both have the ability to charge both battery banks and 2) when the engine is off a) the Blue Sea control functions normally and b) therefore if left in the middle position, the 7622 is bi-directional again.

That is correct, but if you leave the blue sea switch in the off position, it would disable the 7622. So yes , if you want all your solar to go to the house leave the switch in the off position. You don't have to remember to change the switch because when you start the engine, the run circuit relay will put the blue sea back into auto mode or bidirectional voltage monitoring capabilities. The open input of the relay is the same as the Blue Sea Switch being in the middle or auto. The main importance of this is that if you had a excessive load that pulled your alternator low, it would disconnect hopefully in time to protect FICM since you are a diesel. This also make the 7622 look unidirectional, because now when the engine is off it will be off and not monitoring the house voltage and turn on if you have a solar charge.

That last observation means if one wants all solar to go to house when camped, the Blue Sea control switch has to be moved to the batteries disconnected position (down), and before driving one has to remember to turn it back to normal.

Actually you only have to move the Blue Sea Switch if you are camped and want to put some of your solar power to your van batteries, other wise just leave it off. The relay circuit will always turn it to auto mode when the engine is running.

I am afraid I don't understand what this means. If SPDT PN2146 is relay #2, 87a is part of it. Do you mean SPDT PN1246 is the Blue Sea 6007?

Yes, I am sorry that was a little confusing, the SPDT PN2146 is just the Blue Sea Switch, PN2146 is the Blue Sea Part Number. If you did not want to use the Blue Sea Switch you could just tie 87a to ground. That would disable the 7622 while parked, just like if the switch was off.


Yes, feel free to PM me

-greg

[coyotearms]

Greg, Great! I forgot that engine off means control comes back to the Blue Sea Control switch (PN 2146) and as long as that switch is down (banks disconnected position) all solar goes to house when engine is off and to both banks when engine is on. Don't touch anything and it functions just like the Sure Power 1514 (uni-directional) separator. And with one possible caveat, if a dash switch is used to apply +12v from house circuit to terminal 30 of your relay #2, one also has the emergency start function from the drivers seat. That one caveat is that I wonder if it is o.k. if the dash switch in the on position would hurt anything when the engine was running, because in that case the 6722 is connected due to sensing charging of the mains by the alternator AND by that dash switch. That seems to be an issue that could need more knowledge of the inner workings of the separator circuit. What do you think?

-Fred

[Scalf77]

Should be no problem to use the switch for a emergency start, when the van stats running the 7622 would go back to auto. It would be no different then having the switch on, starting the van and then turning the switch to auto. Even if you did not have the extra relay, and had the switch on while running it would not hurt the 7622. But you would loose the auto disconnect if the voltage went to low.

-greg

[coyotearms]

Today I purchased the Blue Sea 7622 and will very shortly install it in the simplest way possible with the connection to engine and house batteries, ground and connecting the "remote" wire to my existing dash button circuit that provides 12v from the house bank to combine battery banks for emergency starting "left over" from the Sure Power uni-directional separator the 7622 is replacing. I will leave for later the wall mounted switch, which in my case is somewhat difficult to do. I will also see how it goes with bi-directional battery management, i.e. whatever bank gets to the threshold voltages via the alternator or solar connects the banks. If that does not work to my satisfaction, I will then add the relay and wiring so nicely figured out by Scalf77 in his most recent past schematic above.

What convinced me to try bi-directional for a while was a call to Blue Sea. I was told that even though boaters usually give much higher importance to making sure start batteries are always charged, the reason Blue Sea only makes a bi-directional separator is because, "it all works out." First of all, bigger boats usually have engine generators, auxiliary generators AND solar. Those systems usually incorporate high current switches such as Blue Sea also sells (also seen on some of Scalf77's schematics) to manually deal with that important task. I was told that it is a different story for smaller boats with outboard engine(s) that bristle with electronic gear. There a uni-directional separator makes sense. This is because the engines usually don't have more capability for charging than it takes for their use, yet the electronics is so important and demanding that solar systems need to work hard to keep up that fancy stuff like radar and fish finders, and rope starts are available in many cases---makes sense to me. They also told me that a bi-directional separator in an RV ends up "favoring" the house bank when solar is working because both banks will not be connected when either 1) the house bank is low, even with solar coming in, the battery voltage won't be high enough and 2) when there are house loads on that bank, again, the voltage will at times be too low to connect the banks---makes sense to me too. And let's face it, if you cannot start your RV with the help of the house bank, it is usually not a life/death situation!

So by installing the 7622 now in the simplest manner as described above and given a trip to Alaska that is coming up shortly, this is a good time to see how well bi-directional charging works. That solution also seems appropriate because I just replaced my six year old AGM engine batteries with top of the line Diehard AGM's (http://www.sportsmobileforum.com/vie...p?f=14&t=11960). Since my three Deka house batteries are still in pretty good shape, I also feel more comfortable using the bi-directional system for those times when the van does not get driven as frequently when at home, even though I try to get 'er out every week or so if it is a long enough drive to get everything to operating temperatures and have a chance to accelerate strongly at least once.

I also made a call to Blue Sky, whose solar controller I use and had a fascinating discussion with them about tweaking some of my three-stage charging parameters. The most interesting aspect was the suggestion to "equalize" the batteries, something I thought of as a no-no for AGM's. By "equalize" I was told that means enable equalizing in the controller and set the Accept Charge voltage to the maximum allowed for about an hour once every 15 days or so. For example Deka gives optimum and maximum Charge voltages of 14.45 and 14.75 @ 60-70F, so using 14.4 and 14.6 for Accept Charge and Equalize makes sense, and it is still a little conservative for both as over charging is the WORST thing for AGM's. I am also a little conservative with Float voltage. Where Deka says optimum and maximum Float voltage should be 13.55 and 13.85, I use about 13.4. NOTE what I actually set the Blue Sky controller to is slightly different (lower) than the above voltages because what they want are values that correspond to 25C (77F). The built-in temperature compensation takes care of actual temperatures. In fact, the unknown exactl accuracy of the temperature compensation is the main reason I like to go a little conservative with set voltages.

The only mystery left to figure out is to make sure Deka house battery voltages are also o.k. for The Diehard engine batteries. The reason this worries me is because engine charging systems really are not designed to charge batteries to their ultimate charge state as that takes multi-stage charging electronics that is not usually (never?) found in vehicles. ANYONE OUT THERE HAVE SOME KNOWLEDGE IN THAT AREA? Sears is not the best place to get that kind of info!

I am sorry this post got so long! But I learned so much from this thread and was motivated by it to learn more that I wanted to share some of it. It is amazing how deep some of this stuff gets when the main goal is to just get out of town at hit the open road once and awhile.

Edited 4/7/2014: The Deka house batteries I have are model 8A27M. And the actual (@ 25 C) voltages that I input into the Blue Sky controller (Solar Boost 3012iL with IPN ProRemote) were: Accept Charge Voltage = 14.3, Float Voltage = 13.4, Equalize Voltage = 14.6 for 2 hr every 15 days. I also chose a temperature compensation slope = -4.3 mV/degree C/per battery cell, which I calculated from Deka voltage vs temperature data in their their Technical Manual, "Valve-Regulated Lead Acid (VRLA): Gelled Elecgtrolyte (gel) and Absorbed Glass Mat (AGM) Bateries."

Editted 2/5/2015: Above I mentioned a planned three-month trip to Alaska (http://www.lugnutlife.wordpress.com) when we would get more experience with the default bi-directional function of the Blue Sea. Even when we used campgrounds we rarely picked sites with power. Admittedly, with 24 hours of sun during part of the trip, the amount of solar was not typical for many places, but the sun wasn't high in the sky much of the time either. Anyway, under those conditions we did not have concerns with the bi-directional functioning. It became clear that quite often during solar charging and when we were using electrical things, especially 110v stuff with the inverter on, we could hear the Blue Sea disconnecting (it is quite loud) as those things brought down the battery voltage enough. I have to say, however, I don't remember hearing such when our all-electric DC refrigerator cycled on. From that experience we don't see it a necessity to modify the circuitry of the install to make the Blue Sea uni-directional, but it would be nicer to install the three-way switch (connect, disconnect, auto) that comes with the unit to manually choose to disconnect the engine and house banks at those times when solar does not seem quite adequate and we want every photon of charge to go to the house bank. After all, we have a 2.5 gal AC water heater that we are able to use at times of abundant solar, say, traveling around the SW USA in summer. While the van sits at home and not driven every week, however, keeping both banks charged (which we can do even through a Seattle winter with at least the CO and propane detectors on) by throwing the switch to auto (the default mode w/o the switch) would be very nice. So installing that switch is now on the to-do list.

EDITED 2/26/2015: I finished the installation of the Blue Sea remote control switch P/N 2146 for the battery isolator 7622. I wired it slightly differently than the instructions with terminal 3 getting +12V when the existing dashboard emergency start button is pressed and with terminal 8 getting +12v from a wire near the location of the switch (instead of both terminals getting +12V all the time. So now in the CONNECT position of the switch, the house and engine battery banks are only ENABLED to be connected via the dashboard switch. The AUTO and DISCONNECT positions of the switch work normally and all lighting modes of the LED's (both are either on or off) work normally. Most importantly, when in the DISCONNECT position, I can be assured that solar charging is totally dedicated to the house battery bank when camping and when solar might be limited (the whole idea behind installing the remote switch).

Also note that the switch is installed in a 1 gang 14 cubic inch "old construction" plastic electrical box and the fuse holder shown below provides protection for the +12v for the LED circuit using a 2 Amp AGC glass fuse.