Victron DC to DC Charger install
- Thread starter jkidd
- Start date
jkidd
Active member
I got the DC to DC charger install done over the weekend and did some testing with a 15 amp charger hooked to the starting battery. I put the charger in the port lazarette hung from the bottom of the stern cleat. Should work pretty good there. Trying to keep the wires as short as possible. Next I need to find out why my battery monitor stopped working so I can test some more.
Jody,
Looks good!
I'm following your thread closely. I plan to use the same Victron charger.
Other than the cables between your starter battery to the DC to DC charger, is there any wiring or switch between the two batteries? Could you start your outboard engine from the house battery if needed?
Looks good!
I'm following your thread closely. I plan to use the same Victron charger.
Other than the cables between your starter battery to the DC to DC charger, is there any wiring or switch between the two batteries? Could you start your outboard engine from the house battery if needed?
jkidd
Active member
Knipet":dq4eodwe said:
The start battery has a disconnect switch on it and the house battery has a disconnect switch on it. There is a second switch on the start switch that will disconnect power to the dc to dc charger so it can be disabled if you need to. The input and output positive leads each have. 60 amp fuses in them. The leads are #6 awg. The only test I have done so far is to hook an 18 amp charger to start battery and let both chargers go through a charge cycle. Bulk charge mode lasted maybe 20 minutes before it switch to absorption mode. Nothing got hot at all both batteries went into float mode.
Ordered a new battery monitor one that has temperature on it I will be able to use that to either disable charging if the temp gets to cold or turn on snowmobile hand warmers stuck to the sides of the battery case to warm the battery up for charging. I will just monitor for right now to see if I need to go that far.
If the weather permits this weekend I need to service the motor. Then I will discharge the house battery to 90 percent and use the motor to recharge and monitor temps on the charge coil. So far it doesn’t look like I need to change from the 30 charger to the 18 amp charger. I don’t think it will be in bulk mode long enough to get things hot. I’ll have some better numbers after I get this test done.
I removed the combiner switch because you can’t use the lithium battery to start the motor I have a jump start battery for emergencies.
jkidd
Active member
I replaced my Victron battery monitor with a new one that will do temperature and has blue tooth. I want to use the old one with the cranking battery. Suzuki minimum cca is 512 and the shunt is a 500 amp. I can short the terminals of the shunt while starting the motor and hook up the meter and the power after the motor is running. Do you think I’ll blow anything up? This will let me watch both sides of the charger.
If you got the Victron BVM 712 battery monitor, I believe it will also give you the voltage of the starter battery, independent of the house battery. I would think that monitoring just the voltage of the starter battery should be enough since other than starting, it shouldn't have much draw.
jkidd
Active member
Knipet":2759zl2s said:
I did get a 712 but I used the connection for temperature for the lithium battery.
I only need to put the shunt in temporary so I can measure the output current of the charge coil against the output current of the dc to dc charger. This is just for information. I would think that the engineers at Suzuki wouldn't publish the charge coil is a 40 amp unless it was and there would be a margin of error also If you gave it 50 amps of things to run it is still going to deliver 40 amps and what ever you trying to run isn't going to run right.
I kind of like taking the mystery out of things so I know exactly what it is doing and not just making a guess. If I take the house battery down to 90 percent and run the motor at idle to charge it back up I should know what the current in and out of the dc to dc charger is doing and if the charge coil is getting hot.
I'm also going to get numbers at 1000 rpm. My thinking right now is if the charger can't get enough current from the motor it might only deliver 20 or 25 amps to the house battery. When I hooked up the 18 amp charger everything worked and both batteries came up to float mode, but I didn't have anything hooked up to tell me what the current was.
Great discussion. I'm considering using the Victron charger in a more complex system. Is this diagram conceptually correct?
I want to be able to use four charging sources (outboard alternator, generator, shore power, and solar) to charge both start and house batteries. I'd like to utilize some of them simultaneously. For example, both the outboard alternator and solar panels while underway, or solar panels and generator while anchored on a cloudy day, etc. I know I would need to make provisions for not exceeding current levels at particular points, but I'm just considering the concept at this time and wondering if this will work. Thank you.
I want to be able to use four charging sources (outboard alternator, generator, shore power, and solar) to charge both start and house batteries. I'd like to utilize some of them simultaneously. For example, both the outboard alternator and solar panels while underway, or solar panels and generator while anchored on a cloudy day, etc. I know I would need to make provisions for not exceeding current levels at particular points, but I'm just considering the concept at this time and wondering if this will work. Thank you.
Jody, Sounds like a well designed and valid experiment. You mentioned you were going to monitor the heat of the "charging coils". Hopefully this will be easy to do. I believe it is essential in the experiment.
The start requirement for the Suzuki 115 is 512 amps CCA. The usual start current draw for this engine max Is in the 150 amp range. I believe the shunt should handle this easily. You could put the clamp on meter over the start cable and see what it draws.
Another depth to the experiment--and it may put more load on the outboard charging circuit, is to draw down the starting battery to 50% (resting voltage of 12.2) and then measure current from outboard charger circuit with and without the DC to DC charger.
I suspect that the start battery acts as sort of a "buffer" for the outboard charging circuit, if the Victorn acts like the Sterling which I have.
.
The start requirement for the Suzuki 115 is 512 amps CCA. The usual start current draw for this engine max Is in the 150 amp range. I believe the shunt should handle this easily. You could put the clamp on meter over the start cable and see what it draws.
Another depth to the experiment--and it may put more load on the outboard charging circuit, is to draw down the starting battery to 50% (resting voltage of 12.2) and then measure current from outboard charger circuit with and without the DC to DC charger.
I suspect that the start battery acts as sort of a "buffer" for the outboard charging circuit, if the Victorn acts like the Sterling which I have.
.
pcg":1ppnseun said:
That is what I do...this unit
https://www.renogy.com/dcc50s-12v-50a-d ... with-mppt/
is the heart of my 12 volt system. It will charge at up to 50 amps total, balancing either from the main motor (Honda 90) alternator, my 525 watt panels, or both at the same time.
You hook the system to cables coming from the starting battery, to solar, and then out to the house batteries.
One other advantage of this combined system is that it priority charges the starting battery from the solar panels if the motor is off. Normal solar chargers don't do this.
One down side is that it is 12 volts only. I bought Renogy batteries initially (a lot cheaper then Battle Born), but it says hooking in series will damage them and the BMS won't allow it, so I moved the Renogys to my camper and put BattleBorn in the C-Dory. BattleBorn claims wiring in series up to 48 volts is no problem, and "so far, so good".
You could also use a 12 to 24 volt converter.
With the LiFePO4's BMS, in theory, I don't need to worry about discharging. I "stressed" the system during the time when I could still return the batteries, and so far I can't overdischarge the batteries unless I specifically program it.
You get so much more from LiFePO4 anyway, I always worried about overdischarging the AGMs when using the trolling motor. It was a definite problem, and I've fished with people on their bass boats that regularly overdischarged their batteries. Then they complained about having to change house batteries every year.
One of the really neat things is when the sun is shining bright to be able to troll simply from the solar panels. Solar-cooled beer also seems to taste better.
For the generator or shore power, I hooked my Cabelas chargers to the batteries, and then the 120VAC into the generator or shore power, but really haven't done that much. One advantage of carrying the generator is that the trolling motors can act as a backup to take me home if the main doesn't work.
Well, that pretty much sums up how I can charge house batteries from 4 sources.
pcg":2uyx3j0q said:Great discussion. I'm considering using the Victron charger in a more complex system. Is this diagram conceptually correct?
I want to be able to use four charging sources (outboard alternator, generator, shore power, and solar) to charge both start and house batteries. I'd like to utilize some of them simultaneously. For example, both the outboard alternator and solar panels while underway, or solar panels and generator while anchored on a cloudy day, etc. I know I would need to make provisions for not exceeding current levels at particular points, but I'm just considering the concept at this time and wondering if this will work. Thank you.
Rob has answered part of the question, and I am not that familiar with the Renology DC DC charger MPPT controller. Thus I only comment on what I am familiar with.
In your diagram, you have basically all of the positive wires (which is only what you show) to the start battery or a bus going to the start battery. I would have my MPPT solar charger going directly to the LI battery. I would have a dedicated LI battery charger for mains and generator charging going directly to the Li battery.
then also the DC to DC battery charger from start battery to Li bank.
If you felt that you needed a charger hooked up to the start battery, I would use an echo charger.
The way you have it has the battery charger going to the start battery and then thru the DC to DC charger. I feel in that way you have significant chance of over charging the house battery. You will not get the best performance out of your Li batteries.
What size solar panel are you going to use?
Rob,
I believe if you have a 2003 Honda 90 only has a 17 amp battery charging output. That is true for the carburetor engines, In 2007 the 90 is fuel injected and has 44 amps, 35 usable for battery charging
thataway":1xm67om4 said:
Yes, and this low charging from the alternator is borne out by my meters. It is a little better than 17 amps @ 12 volts, which would be 200 watts. It shows more like 230 watts. I guess converting 17 amps @ 14.4 volts to amps @ 12 volts.
The LiFePO4 batteries are amazing. When partially discharged only a bit, they seem to take charge very easily with little internal resistance that you see in AGMs. They don't get as hot either. I hooked them up directly to my truck alternator, which is what I initially intended, and it was scary how fast they charged. However, I'd need some pretty large cables to get back into the camper with that high a current. 50 amps is fine.
The Honda 17 amps current does add up over time, but I'd love to get closer to that 50 amps I can use with the system I have.
This Renogy system seems unique to me. I don't know of any other device that offers so much, combining alternator and solar, and charging the starter as well as the house from solar. However, if it fails, several things fail at once.
The nearly 20-y-old carburated Honda 90 offers little justification for replacement other than it is old and I worry about it. If I don't replace it, it may outlast me. Same with my 23-y-old Honda generator, the one that was too heavy to steal (my only complaint about Honda generators).
My goal is to keep all batteries charged, using any or a combinations of the four charging sources. I thought the whole point of using an appropriate DC to DC charger was to ensure that the LiFePO4 battery bank was charged properly (i.e. no overcharging, proper algorithm, etc.)thataway":vx94poqo said:
Rob,
I'd really like to see photos of your 525watt solar array, I imagine on a summer sunny day it does a good job of charging your batteries. If no photos, where do you have them mounted? How many LiFeP04 batteries do you have and how many Ah? I assume you need the 24v system for your trolling motors?
Question for the group:
I'm confused about the Outboard's alternator to DC to DC charger relationship concerning a LifeP04 battery. Do you need to sized the DC to DC charger large enough to accept what the alternator can give it? Or get one that limits the amperage to the LiFeP04 battery to not overheat the alternator since LiFeP04 batteries can mostly absorb as many watts as given to them?
I'd really like to see photos of your 525watt solar array, I imagine on a summer sunny day it does a good job of charging your batteries. If no photos, where do you have them mounted? How many LiFeP04 batteries do you have and how many Ah? I assume you need the 24v system for your trolling motors?
Question for the group:
I'm confused about the Outboard's alternator to DC to DC charger relationship concerning a LifeP04 battery. Do you need to sized the DC to DC charger large enough to accept what the alternator can give it? Or get one that limits the amperage to the LiFeP04 battery to not overheat the alternator since LiFeP04 batteries can mostly absorb as many watts as given to them?
I think this is a "problem" that many of us have. I felt that way when I had the 90 hp with carbs, for more charging and without the problem of having the drain the carbs each time I was not using the engine in a few weeks.
Now with the 13 year old 150, I would love to have 200 hp on the 25...but no way. Fortunately the 150 puts out in the 44 amp range, so 30 amps to the batteries is fine. The 17 amps "available" may be taken by electronics or bait tanks etc. We find that an average days run restores the LiFePO4 batteries to close to full charge (Victron. meter) We run the freezer and refrigerator, plus induction burner off the Li bank, There remains a lead acid group 27 house battery, which runs the electronic, lights, fans etc. This is charged via a conventional VSR.
Yes, you are correct. However, from mains power, I used a battery charger profiled for lead acid batteries, and turn off the DC to DC charger. I use a second battery charger which is profiled for the Li battery bank. In my case that is an 80 amp charger off the Victron Multiplus inverter charger.
What you are doing is putting all charging thru the battery, which will be limited in output by the DC to DC charger (if you have a 90 hp Honda, this is 18 amps) and runs some risk of over charging and the shortening the life of the start battery. One of the major advantages of the LI battery is quick charge, as Rob pointed out.
When you are cruising, the start battery should be kept pretty well up to full charge state by the outboard charger. When not in use, it should have minimal self discharge, being an AGM battery.
Depending on how big the solar panels are, the MPPT controller will give much more charge than the DC to DC charger can handle.
I may ask why are you considering LiFePO4 batteries? I have gone back thru your photos and some of your threads. Nothing left me convinced that your boat was a good candidate for Li battery. Also what amount of solar power, and why? If most of your boating is in the PNW, solar power is not as good as lets say, Lake Powell. What are the big draws of power going to be?
I am using the Li for several reasons--first I want a light weight high capacity bank for an all electric galley (Microwave and induction cooking), second I have the fairly high draw of a freezer and refrigerator (chest types). This bank is separate from the flooded lead acid which were adequate for prior owners, who used propane cooking. Also, I had been following Li technology for over 15 years in RV and more recently in boats, so I wanted to experiment with it, and see if it is worth while recommending. (Both boats and RV's). I did not put Li in my RV. We rarely doonbock, and we have a 200 amp alternator and diesel generator, with propane refrigerator and cooking. (does have a microwave and air conditioning, which we run the generator for.)
Yes, that makes sense and was a concern I had.thataway":3c62y0k0 said:
We are planning to use this boat primarily for boondocking in the PNW. We may go days without starting the outboard and will have refrigerator, freezer, lighting, computers, etc. to power. We have spent many years boondocking in an RV, but we relied upon propane for refrigeration and won't be doing that with the boat. We'll have solar, but may have days of rain to contend with. I want the increased energy storage capacity and light weight of LiFePO4.thataway":3c62y0k0 said: