You state that you want it to do both, but you mention 3 charge requirements - when driving - when in sun - when you have electricity.
The BCDC can do the first two, but not the third, you will need a 240v mains charger for that.
You haven't stated what your load will be, for how long you will drive, or how much solar you will have, so it's a bit hard to give a definitive answer as to whether the BCDC will be able to keep your house battery sufficiently charged.
I assume that your crank battery set is 24v and the house is 12v. If this is the case, then that circuit will be good, the BCDC 1240 will charge the house from the vehicle alternator or from the solar.
Be aware that it won't do both at the same time as can be achieved with a separate solar controller.
From memory, the BCDC devices can't handle 24v panels due to their open circuit voltage being too high for it. You may want to check that point before getting your panels if you were intending to use anything higher than 12v ones.
Using one device to perform multiple tasks always carries the risk of redundancy in that if the device fails, you have lost all forms of charging. Separate engine and solar charge controllers would reduce this possibility as it is less likely for both devices to fail simultaneously.
With this in mind, you should make your decision based on your confidence in the device not to fail.
Hope this helps.
oldbobsbus said
05:09 PM Nov 27, 2013
I have just changed my house batteries and solar system from 12v to 24v so now both the house and the start are 24v
The house is running independent of the start system but can be connected if needed.
The house is generally charged by the solar but there is an inverter charger there so if need be it can be used to bring the house or start batteries up when connected to shore power.
With very little effort the start batteries can also be connected up the get a boost from the solar system. As can the house batteries be connected to get a boost from the alternator when traveling if required.
There were too many hassles when the house was 12v and the start was 24v
SnowT said
09:25 PM Nov 27, 2013
Brian you have brought up a very valid Point.. you can't use the one thing to do 2 thing's at once..
I now have to go back to the drawing board..[Which is a good thing, it still in the work's]
- bob have a Question... did you have to change the low voltage stuff in your setup..? or are you using a 24/12 convertor..?
Just by chance what batteries are you using.. and the configuration..
It will help me..
Juergen
Aus-Kiwi said
10:27 PM Nov 27, 2013
Depends how batteries are wired up...
oldbobsbus said
06:59 AM Nov 28, 2013
SnowT wrote:
- bob have a Question... did you have to change the low voltage stuff in your setup..? or are you using a 24/12 convertor..?
Just by chance what batteries are you using.. and the configuration..
It will help me..
Juergen
this is my setup and I am using a 12/24v controller/regulator.
There is also a photo of the setup a couple of posts down, I had to change both inverters from 12v to 24v input. but everything else stayed the same as the panels were putting out 32v..
SnowT said
02:05 PM Nov 28, 2013
Bob had a Look at your set up..
If I have it right your running 4 @ 12 v Batteries.. of 200ah range..
In a Series / Parallel configuration..
12v + 12v -- 24v
12v + 12v -- 24v
Your 24v 400Ah
If that is the setup are you running any Low voltage light's etc..?
I do like the setup..
Now to rework my cost's..
Juergen
oldbobsbus said
03:11 PM Nov 28, 2013
SnowT wrote:
Bob had a Look at your set up..
If I have it right your running 4 @ 12 v Batteries.. of 200ah range..
In a Series / Parallel configuration..
12v + 12v -- 24v 12v + 12v -- 24v
Your 24v 400Ah
If that is the setup are you running any Low voltage light's etc..?
I do like the setup..
Now to rework my cost's..
Juergen
Yep off to the right of the controller I have a 24v to 12v converter that runs my 12v water pump and reversing camera, I also have another converter inside that I run some 12v LED lights from as I have run a 24v twin enclosed lead to a point inside the bus..
Apart from that everything in the bus is 240v ...
SnowT said
07:00 PM Nov 28, 2013
Bob,
I was hoping that I did not have to use a 24/12v convertor..
Juergen
oldtrack123 said
12:23 PM Nov 30, 2013
HI Snow
I believe your system is ALL 12V
If so I do not see ANY POINT IN even considering anything involving 24V
The Redarc BCD 1240 is a 12V unit
As others have said the Redarc unit will only select ONE source at ANY TIME
You would be better ,IMHO,to keep your solar seperate with it's own regulator & connected direct to the HOUSE batteries
Then use a DC to DC charger from the alternator,or possibly even just a direct charge connection via an isolating relay [VSR]
The MAINS charger can remain connected as well
However, we would need to know the alternator output voltage before making a decision on THAT
l would expect both the house batterries & the crank Batterries are close together?
So VOLTAGE drop should not be a problem if good sized cables are used!!
The above will give the sources the abilty to work together
Especially when the house batterries are in a low state of charge [LOW S.O.C]
More details of solar capacity ,house battery bank ,Mains charger ,AND vehicle Alternator could help
PeterQ
-- Edited by oldtrack123 on Saturday 30th of November 2013 12:28:02 PM
-- Edited by oldtrack123 on Saturday 30th of November 2013 12:29:21 PM
SnowT said
01:59 PM Nov 30, 2013
Sorry Peter.
I'm in the design phase of the project.. I'm in the stage were I can afford to do the change's..
- Toyota Coaster Bus is going to be the base unit.. - run's a main 24v system for base battery configuration..
House Battery location at this time is up in the air.. - Possible Location is under the main Bed..[One issue is the weight will be to the back..] - If I go with under the Bed the Distance between Battery's will be about 4-5m of cable.. think or running a 70-100mm cable setup..
Solar aiming for 600-750w of solar.. 24v panels' 3 of..
Bus Electrics - 24v
Cables for the system shall be bought from CIG or any welding supply store as they sell the cables cheaper than anyone I know of..
So Basically, I'm after the best information I can get.. - From what I have gotten here is.. 1 - try to match the bus Electric's.. 2 - Individual charge controllers - DC-DC, Solar, 240v charger..
Juergen
-- Edited by SnowT on Saturday 30th of November 2013 02:01:50 PM
brian said
04:55 PM Nov 30, 2013
Personally, I would not be using 24v house, simply due to the limited availability of 24v equipment as compared to 12v stuff.
You are contemplating a DCDC charger anyway, so get a 24v to 12v one.
Most MPPT controllers will easily handle 24v panels to 12v battery charging.
Connect a couple of 12v batteries in series to get 24v, and one goes bung, you have no power.
Connect a couple of 12v batteries in parallel and one goes bung, you still have power, albeit at less capacity.
If you are going to do it like Bob, and simply use inverters to supply everything at 240v, then by all means, go the 24v route.
oldtrack123 said
05:51 PM Nov 30, 2013
brian wrote:
Personally, I would not be using 24v house, simply due to the limited availability of 24v equipment as compared to 12v stuff. You are contemplating a DCDC charger anyway, so get a 24v to 12v one. Most MPPT controllers will easily handle 24v panels to 12v battery charging. Connect a couple of 12v batteries in series to get 24v, and one goes bung, you have no power. Connect a couple of 12v batteries in parallel and one goes bung, you still have power, albeit at less capacity. If you are going to do it like Bob, and simply use inverters to supply everything at 240v, then by all means, go the 24v route.
HI
I agree
But a warning ,IF you go ALL 240V from an inverter into fixed wiring .feeding mulitple sockets & appliances IT MUST COMPLY to AS 3000 & AS3001 AND SUCH WIRING SHALL BE CARRIED OUT BY A LICENSED ELECTRICIAN
PeterQ
oldbobsbus said
06:05 PM Nov 30, 2013
I know that Peter
SnowT said
07:39 PM Nov 30, 2013
Peter
I'm a sparky by Trade..
Have been working in the trade for over 20yr's..
And Some of the stuff I have seen is scary.. Especially when it's in a Van that has Metal cladding..
It's also one of the reason.. I'm gob smacked with the cost of the Double Pole Switches and GPO's..
Juergen
oldtrack123 said
08:43 PM Nov 30, 2013
SnowT wrote:
Peter
I'm a sparky by Trade..
Have been working in the trade for over 20yr's..
And Some of the stuff I have seen is scary.. Especially when it's in a Van that has Metal cladding..
It's also one of the reason.. I'm gob smacked with the cost of the Double Pole Switches and GPO's..
Juergen
Hi Snow
That's good to hear
If you cannot get access to, or need any help with the requirements of AS 3001, just PM me
I do not put THAT sort of info on an open forum
Some may think they know it all & try to do it themselves!!!
PeterQ
SnowT said
08:51 PM Nov 30, 2013
Hey Peter one of the main Reason's I'm being a Pain in the Butt in the Techie Forum's is, that I don't Know Everything.. I know enough to be down right Dangerous.[And would rather get it right than Screw up]
I'm always Learning new thing's, so I keep on asking/making some dumb question's..
Better to Learn the right way, than to be ignorant of the right way to do thing's..
Juergen
oldtrack123 said
09:18 PM Nov 30, 2013
SnowT wrote:
Hey Peter one of the main Reason's I'm being a Pain in the Butt in the Techie Forum's is, that I don't Know Everything.. I know enough to be down right Dangerous.[And would rather get it right than Screw up]
I'm always Learning new thing's, so I keep on asking/making some dumb question's..
Better to Learn the right way, than to be ignorant of the right way to do thing's..
Juergen
Hi Juergen
I rarely consider a genuine question, dumb
So ask away
Ps I for one, believe Myself or anyone else is EVER too old to learn
But am always cautious that what I post is well founded on known facts,& many, many years of experience across a very wide range of the electrical & engineering fields.
PeterQ
Baz421 said
09:27 PM Nov 30, 2013
FYI if interested, this is a good link. Posted it ages ago but reserected again.
It does Not include any DC appliance to be hooked up..
As a Note..
I'm sort of Leaning towards having 2 Heavy Duty Buses to Hook up Both the -ve and the +ve in the DC circuit's To Allow me to Have DC fuses in the Mix..
HI J Just a lttle tip on Parallell battery interconnections IF it is not too difficult ,Always have equal resistance in the charge & load cables of the battery interconnections
It can be an advantage if high load currents are drawn from the house batteries The batteries will share the current more evenly t With a two PARALLELL battery set up that simply means use the same size & length PARALLELLING interconnections. THEN take both the load & Charging cables from the Pos of one battery & the NEGs from the other battery
Also keep the solar reg as close to the house batteries as possible max voltage drop [with FULL current] between reg & batteries should not EXCEED 0.2V
The lower, the better SOC of the batteries
The same applies to the DC/DC charger
Use your voltage drop tables to calculate cable size for run length & current
Yes, you definately should have fuses/ dc olcbs at the Start of all the Dc circuits.
Depending on how the main DC feeds are ,a Main dc fuse or Dc circuit breaker as close as practical to the batteries PeterQ
-- Edited by oldtrack123 on Saturday 30th of November 2013 11:24:03 PM
-- Edited by oldtrack123 on Saturday 30th of November 2013 11:28:57 PM
-- Edited by oldtrack123 on Saturday 30th of November 2013 11:31:03 PM
SnowT said
11:46 PM Nov 30, 2013
Ok Peter..
If I have it correct from what your saying.. It should Look Like this..
I'm not at present close to a calculator, but some of those cables look way overkill for the currents that you are likely to be passing. Maybe you can tell us what size your dcdc charger and other equipment is.
I assume that the solar controller is an MPPT type, as a series one will be no good for charging 12v batteries from 24v panels.
oldtrack123 said
12:07 PM Dec 1, 2013
Hi J
we need the run lengths & MAX currents in the cables to CHECK
If you can show that ,, we can check it out
Brian's comments re panel arrangement is a valid question ,but I would expect you are going for parallelling
[ nominal12V] output??
It is has an advantage over shading with series connection .
When combining mulitple charge sources ,a mppt reg can ,at times be a disadvantage , It may have diificulities ,at times , in matching the MPP of the panels to the load,due to intereaction with the other connected charging sources
This is one of the reasons the Redarc Only runs on one source at any time
This will not be harmful to any of the equipment involved.
A simple solution, if it does become a limiting problem ,is to have an isolation means in the other charging sources OR simply use a PWM reg
PeterQ
SnowT said
12:36 PM Dec 1, 2013
Now this is WHY I need to Ask the Dumb Question..
Yes the Solar panels shall be Paralleled up..[the drawing was wrong in that Area..]
Ok I have more information for you.. I'd Rather go Over size, than under size..
Basically I'm after a Panel to help me meet My running/charging the system to a high standard..
the higher the Better
Juergen
brian said
04:49 PM Dec 1, 2013
Those panels are physically pretty big, are you sure that you can accommodate them on the roof, having due regard to avoiding shading from vents, air-conditioner etc?
The voltage of those panels basically excludes the use of a series type solar controller, so you will need to use an MPPT device. The Redarc unit does not have a high enough operating voltage and Morningstar make both types in 45 amp, so be a bit wary.
I would suggest that you wire the panels separately to the controller rather than paralleling them up top.
I don't know what distance you have from the crank battery to the DCDC charger, so can't give you a size for that, but 8AWG (about 8mm²) will be quite adequate for the others, giving a maximum voltage drop of less than 0.3v at 40 amps for the charging circuits, and allowing that much again for downstream losses.
You could use various size wires for the links etc. but it's generally easier to buy just one suitable size cable and lugs for the lot
Looking at what I need for the Motorhome..
I want to make sure that the house batteries are at full charge at all time's possible..
- I want to be able to charge the Batteries when I drive and also when I'm parked somewhere that has sun or Electricity..
My question is...
Is a REDARC BCDC1240 the best way to do Both...
I have read the instruction document and it seems that I can use the 1 device to do both job's and it has a MPPT charge circuit in it..
Page 11, figure 2.6 is what I think is the best method of wiring the system..
IF I'm wrong please tell me..
This will save me money..
by not having to buy a DC-DC charger and a Solar regulator..
Juergen
You state that you want it to do both, but you mention 3 charge requirements - when driving - when in sun - when you have electricity.
The BCDC can do the first two, but not the third, you will need a 240v mains charger for that.
You haven't stated what your load will be, for how long you will drive, or how much solar you will have, so it's a bit hard to give a definitive answer as to whether the BCDC will be able to keep your house battery sufficiently charged.
I assume that your crank battery set is 24v and the house is 12v. If this is the case, then that circuit will be good, the BCDC 1240 will charge the house from the vehicle alternator or from the solar.
Be aware that it won't do both at the same time as can be achieved with a separate solar controller.
From memory, the BCDC devices can't handle 24v panels due to their open circuit voltage being too high for it. You may want to check that point before getting your panels if you were intending to use anything higher than 12v ones.
Using one device to perform multiple tasks always carries the risk of redundancy in that if the device fails, you have lost all forms of charging. Separate engine and solar charge controllers would reduce this possibility as it is less likely for both devices to fail simultaneously.
With this in mind, you should make your decision based on your confidence in the device not to fail.
Hope this helps.
The house is running independent of the start system but can be connected if needed.
The house is generally charged by the solar but there is an inverter charger there so if need be it can be used to bring the house or start batteries up when connected to shore power.
With very little effort the start batteries can also be connected up the get a boost from the solar system. As can the house batteries be connected to get a boost from the alternator when traveling if required.
There were too many hassles when the house was 12v and the start was 24v
I now have to go back to the drawing board..[Which is a good thing, it still in the work's]
- bob have a Question... did you have to change the low voltage stuff in your setup..? or are you using a 24/12 convertor..?
Just by chance what batteries are you using.. and the configuration..
It will help me..
Juergen
this is my setup and I am using a 12/24v controller/regulator.
http://thegreynomads.activeboard.com/t55628528/assembling-battery-bank-using-different-capacity-units/
There is also a photo of the setup a couple of posts down, I had to change both inverters from 12v to 24v input. but everything else stayed the same as the panels were putting out 32v..
If I have it right your running 4 @ 12 v Batteries.. of 200ah range..
In a Series / Parallel configuration..
12v + 12v -- 24v
12v + 12v -- 24v
Your 24v 400Ah
If that is the setup are you running any Low voltage light's etc..?
I do like the setup..
Now to rework my cost's..
Juergen
Yep off to the right of the controller I have a 24v to 12v converter that runs my 12v water pump and reversing camera, I also have another converter inside that I run some 12v LED lights from as I have run a 24v twin enclosed lead to a point inside the bus..
Apart from that everything in the bus is 240v ...
I was hoping that I did not have to use a 24/12v convertor..
Juergen
HI Snow
I believe your system is ALL 12V
If so I do not see ANY POINT IN even considering anything involving 24V
The Redarc BCD 1240 is a 12V unit
As others have said the Redarc unit will only select ONE source at ANY TIME
You would be better ,IMHO,to keep your solar seperate with it's own regulator & connected direct to the HOUSE batteries
Then use a DC to DC charger from the alternator,or possibly even just a direct charge connection via an isolating relay [VSR]
The MAINS charger can remain connected as well
However, we would need to know the alternator output voltage before making a decision on THAT
l would expect both the house batterries & the crank Batterries are close together?
So VOLTAGE drop should not be a problem if good sized cables are used!!
The above will give the sources the abilty to work together
Especially when the house batterries are in a low state of charge [LOW S.O.C]
More details of solar capacity ,house battery bank ,Mains charger ,AND vehicle Alternator could help
PeterQ
-- Edited by oldtrack123 on Saturday 30th of November 2013 12:28:02 PM
-- Edited by oldtrack123 on Saturday 30th of November 2013 12:29:21 PM
Sorry Peter.
I'm in the design phase of the project..
I'm in the stage were I can afford to do the change's..
- Toyota Coaster Bus is going to be the base unit..
- run's a main 24v system for base battery configuration..
House Battery location at this time is up in the air..
- Possible Location is under the main Bed..[One issue is the weight will be to the back..]
- If I go with under the Bed the Distance between Battery's will be about 4-5m of cable.. think or running a 70-100mm cable setup..
Solar aiming for 600-750w of solar.. 24v panels' 3 of..
Bus Electrics - 24v
Cables for the system shall be bought from CIG or any welding supply store as they sell the cables cheaper than anyone I know of..
So Basically, I'm after the best information I can get..
- From what I have gotten here is..
1 - try to match the bus Electric's..
2 - Individual charge controllers - DC-DC, Solar, 240v charger..
Juergen
-- Edited by SnowT on Saturday 30th of November 2013 02:01:50 PM
HI
I agree
But a warning ,IF you go ALL 240V from an inverter into fixed wiring .feeding mulitple sockets & appliances IT MUST COMPLY to AS 3000 & AS3001 AND SUCH WIRING SHALL BE CARRIED OUT BY A LICENSED ELECTRICIAN
PeterQ
I'm a sparky by Trade..
Have been working in the trade for over 20yr's..
And Some of the stuff I have seen is scary.. Especially when it's in a Van that has Metal cladding..
It's also one of the reason.. I'm gob smacked with the cost of the Double Pole Switches and GPO's..
Juergen
Hi Snow
That's good to hear
If you cannot get access to, or need any help with the requirements of AS 3001, just PM me
I do not put THAT sort of info on an open forum
Some may think they know it all & try to do it themselves!!!
PeterQ
I'm always Learning new thing's, so I keep on asking/making some dumb question's..
Better to Learn the right way, than to be ignorant of the right way to do thing's..
Juergen
Hi Juergen
I rarely consider a genuine question, dumb
So ask away
Ps I for one, believe Myself or anyone else is EVER too old to learn
But am always cautious that what I post is well founded on known facts,& many, many years of experience across a very wide range of the electrical & engineering fields.
PeterQ
FYI if interested, this is a good link. Posted it ages ago but reserected again.
http://www.smartgauge.co.uk/batt_con.html
What I have nutted out so far..
This is My Mud map so far of the DC Wiring..
It does Not include any DC appliance to be hooked up..
As a Note..
I'm sort of Leaning towards having 2 Heavy Duty Buses to Hook up Both the -ve and the +ve in the DC circuit's To Allow me to Have DC fuses in the Mix..
Hope this help's with the whole concept so far..
Juergen
HI J
Just a lttle tip on Parallell battery interconnections
IF it is not too difficult ,Always have equal resistance in the charge & load cables of the battery interconnections
It can be an advantage if high load currents are drawn from the house batteries
The batteries will share the current more evenly
t
With a two PARALLELL battery set up that simply means use the same size & length PARALLELLING interconnections.
THEN take both the load & Charging cables from the Pos of one battery & the NEGs from the other battery
Also keep the solar reg as close to the house batteries as possible max voltage drop [with FULL current] between reg & batteries should not EXCEED 0.2V
The lower, the better SOC of the batteries
The same applies to the DC/DC charger
Use your voltage drop tables to calculate cable size for run length & current
Yes, you definately should have fuses/ dc olcbs at the Start of all the Dc circuits.
Depending on how the main DC feeds are ,a Main dc fuse or Dc circuit breaker as close as practical to the batteries
PeterQ
-- Edited by oldtrack123 on Saturday 30th of November 2013 11:24:03 PM
-- Edited by oldtrack123 on Saturday 30th of November 2013 11:28:57 PM
-- Edited by oldtrack123 on Saturday 30th of November 2013 11:31:03 PM
Ok Peter..
If I have it correct from what your saying.. It should Look Like this..
Juergen
Hi J
Yes ,you've got it
Then connect the loads, POS to B1 + and Load Negs to B2 -
PeterQ
If I'm correct the cables are as shown..
I have gone over what I think I need.. Found a nice Page that spit's out the Cable size after you input the figure's..
Now let's see if I have it right..
Juergen
Hi J
we need the run lengths & MAX currents in the cables to CHECK
If you can show that ,, we can check it out
Brian's comments re panel arrangement is a valid question ,but I would expect you are going for parallelling
[ nominal12V] output??
It is has an advantage over shading with series connection .
When combining mulitple charge sources ,a mppt reg can ,at times be a disadvantage , It may have diificulities ,at times , in matching the MPP of the panels to the load,due to intereaction with the other connected charging sources
This is one of the reasons the Redarc Only runs on one source at any time
This will not be harmful to any of the equipment involved.
A simple solution, if it does become a limiting problem ,is to have an isolation means in the other charging sources OR simply use a PWM reg
PeterQ
Now this is WHY I need to Ask the Dumb Question..
Yes the Solar panels shall be Paralleled up..[the drawing was wrong in that Area..]
Ok I have more information for you.. I'd Rather go Over size, than under size..
Juergen
yes..
Possible Solar Panels
Basically I'm after a Panel to help me meet My running/charging the system to a high standard..
the higher the Better
Juergen
Those panels are physically pretty big, are you sure that you can accommodate them on the roof, having due regard to avoiding shading from vents, air-conditioner etc?
The voltage of those panels basically excludes the use of a series type solar controller, so you will need to use an MPPT device. The Redarc unit does not have a high enough operating voltage and Morningstar make both types in 45 amp, so be a bit wary.
I would suggest that you wire the panels separately to the controller rather than paralleling them up top.
I don't know what distance you have from the crank battery to the DCDC charger, so can't give you a size for that, but 8AWG (about 8mm²) will be quite adequate for the others, giving a maximum voltage drop of less than 0.3v at 40 amps for the charging circuits, and allowing that much again for downstream losses.
You could use various size wires for the links etc. but it's generally easier to buy just one suitable size cable and lugs for the lot