Partially? How?
First of all, there's no "ignition" for a diesel engine (just as there's no throttle).
What do you mean by "power drop to the starter motor Solenoid during cranking?"
What "pwr. Relay?"
Wow.
2006 Hunter 41DS House Bank Charging off alternator
- Thread starter twenger
- Start date
First of all, there's no "ignition" for a diesel engine (just as there's no throttle).
What do you mean by "power drop to the starter motor Solenoid during cranking?"
What "pwr. Relay?"
Wow.
I was a marine tech way back in 1980, and since got an electrical engineering degree. I have never seen an ACR fail, for any reason. If they are failing, they are installed in systems for which they are not rated or not appropriate; or, they are improperly installed.
Gentlemen, let's keep this civil. We can agree to disagree and we can have different opinions, just keep it civil and not personal.
Thanks.
Thanks.
I retired as a certified Marine Tech. In 2021, 35 yrs.
Way different than 1980s Technology.
Emission standards, new Boats.
Hey @jviss - yes, I do see exactly what you're saying.
I did some research on this (I didn't fully work out exactly when the solenoid is switched on/off before I wired it out of my system). My understanding is that the solenoid has the the start and house bank paralleled together in the start condition. I don't believe that there's any additional circuitry that switches the solenoid off when the key is turned to 'START'. Note that you could isolate the house bank from the start circuit by switching the house bank battery switch OFF before starting, but I doubt that anyone does that regularly, especially underway (I never did).
The BSS SI-ACR notes as one of its key features that the house bank and starter bank are disconnected during engine cranking. This is definitely a good upgrade.
https://www.bluesea.com/products/7610/SI-ACR_Automatic_Charging_Relay_-_12_24V_DC_120A
I did some research on this (I didn't fully work out exactly when the solenoid is switched on/off before I wired it out of my system). My understanding is that the solenoid has the the start and house bank paralleled together in the start condition. I don't believe that there's any additional circuitry that switches the solenoid off when the key is turned to 'START'. Note that you could isolate the house bank from the start circuit by switching the house bank battery switch OFF before starting, but I doubt that anyone does that regularly, especially underway (I never did).
The BSS SI-ACR notes as one of its key features that the house bank and starter bank are disconnected during engine cranking. This is definitely a good upgrade.
https://www.bluesea.com/products/7610/SI-ACR_Automatic_Charging_Relay_-_12_24V_DC_120A
Yes, thanks! I like BSS products.
I rewired my boat myself, and have a starting battery that is charged via an echo charger from the house bank. The alternator is connected directly to the house bank.
Were I to do it over, which I may, I'd have a LiFePO4 house bank and FLA starting battery, and a DC-DC charger for the starting battery.
My boat is currently wired using the configuration per @Maine Sail 's and others (including me) where the 1/2/B/Off switch selects the house bank or start battery to power the house, with a disconnect switch for the start battery. Here's the schematic I drew on a napkin during a boring tech conference back in 2012:
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jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 22,319
This is true. A special wire connection is required to signal the ACR to interrupt the house and start the battery connection.
My recently completed system is exactly as you describe: LiFePO4 house batteries and a FLA house battery. I really like the setup. I think it does a great job of leveraging the the simplicity/benefits of the older technology on the engine/alternator side and the performance/benefits of the newer technology on the house side.
The LiFePO4 batteries(Battle Born) have proven to be solid performers and extremely reliable through the abuse of living aboard full time. Time has proven that the onboard BMS manages the battery's health far batter than I can (I have caused early death to many lead-chemistry batteries in the past by accidental abuse, mainly due to discharging batteries too deeply combined with poor/short charging cycles). The lithium batteries eliminate those concerns, which makes managing the electrical system significantly less stressful and just plain boring. They "just work".
The house bank is mainly charged with a bifacial solar panel (I am amazed at the performance I am seeing out of the panel, even on cloudy/foggy days). The alternator (internally-regulated, "dumb") does what it does best and directly charges the start battery. It has no direct wiring to the LiFePO4 house bank, achieving separation of the banks at all times (including starting). A programmable DC-DC charger (Victron) bridges the gap between the start battery and the house bank to provide house bank charging when the engine is running. When the alernator isn't spinning fast enough to generate enough power to meet the full, 30-Amp rating of the DC-DC charger, the charger detects the voltage drop and automatically throttles it's charging current down to compensate so that energy isn't pulled out of the starter battery in order to charge the house. I was concerned about how effectively this throttling system would work at first, but so far it's worked extremely well.
The 30-Amp Victron charger generates a fair bit of heat (I understand that the 50-Amp models that Victron just released are signficantly better in this department, along with other improved features). I build a backing plate out of aluminum sheeting and a mount that offsets the unit from the mounting surface. This is probably overkill, but the materials were cheap.
I'm a big fan of the switching setup that you and @Maine Sail propose. I may adopt that switching configuration when I finish the installation of my Victron inverter/charger this fall/winter.
Thanks for the great discussion!
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funny my business installed and sold piles of ACR’s. Yet to see a failed one. i even cut one open a 120A model thad was left in place when the customer upgraded to a 200A alt.
he insisted it was defective. Turns out he had not reconnected ACR gnd. Out of curiosityI cut it open and the contacts were perfect and it still functioned just fine. When Fred designed these the contact spec was drastically upgraded over standard cheap bare coper contacts. Again, these have proven far more reliable than just about any product in the marine electrical market. we had one customer who circumnavigated twice and his ACR proved to be his most reliable electrical component..
Great reply, thanks.
What features have the new ones that are desirable? I've noticed LiFePO4 prices coming down, and DC-DC charger prices coming down, as well. There's a 60A DC-DC charger on Amazon that I'm looking at for $189, brand name LiTime. It has a pretty good set of features. They also have a 1kW inverter for $129. Only downside for me is that the smart display is not remote.
Now that my Incharge smart regulator has died, and there's no viable replacement, and I switched to a Balmar, there's one piece missing from my Freedom 10 ( I think it's a 10) system, and I'm considering abandoning it for some more modern gear.
I attached the data sheets for the older, 30A Orion DC-DC charger and the (released this year) 50A Orion. I don't have direct experience with the new, 50A unit, but I do with the older 30A unit. The main improvements between the two are, besides the greater capacity of the 50A, the 50A comes in a much smaller package and operates much more efficiently. The 30A creates a lot of heat due to its lower efficiency. As an EE, you would probably be better than me at identifying the improvements in the internal electronics that are responsible for the efficiency gains. It doesn't look like it from the picture, but the 30A is pretty hefty unit in real life. The heatsink itself is roughly half the size of the unit.
The user configurability of the 50A has some improvements. Most notably, the 50A can be throttled down through its settings (accessible by Bluetooth and and app on your phone). The 30A's output can't be changed, but as I mentioned before, it's automatic throttling feature has worked very well for me so far. I was very close to buying the 50A when I went to install a DC-DC charger for this reason, but at that point there was limited availability of the 50A and I thought the 30A would still suit my needs well. I don't rely very much on alternator charging.There may be better monitoring built into the 50A's display capabilities. The settings are fantastic on the 30A, but you can't monitor the output of the unit on the app, only its status is displayed. This isn't the end of the world if you have a battery monitor installed, like most of us do, but it's still nice to see this information in one place (like the Victron MPPT SmartSolar charge controllers do).
I'm not familiar at all with LiTime. I generally approach electronics like this on Amazon with a lot of skepticism given how I use my boat (day charters and longer offshore trips). I need electronics that are well-engineered (with marine uses in mind), extremely reliable, consistent, and overall extremely safe. I've been very pleased with the quality, build, and engineering of Victron. From the hardware to the software apps, custom programability, and overall thought of interoperability they put into their systems; I've been impressed at every turn. Once the install is completed, their stuff "just works" boringly well with essentially zero input/maintenance.
I don't want to disparage LiTime unfairly (I honestly don't know the first thing about them), I just approach brands on Amazon with a lot of skepticism. If I was setting up systems in a house or an RV I would think differently and would probably be more open to experimenting. I don't look down on anyone that is looking for better value and wants to experiment. I'm sure there's a lot of value out there. The environment on a boat is just plain harsh and the consequences of failures are generally high. It seems like I, personally, get bit every time I try to go for the low cost option. It seems like I end up revisting that project again in short order to throw more money at it.
You probably know this already given your experience and education, but I'll mention it for anyone else reading: with inverters especially, it's important to only install units that are marine-rated due to special internal switching requirements on a boat. They need to combine the neutral and ground only while they're actively inverting. I haven't brushed up on this lately, but my understanding is that, on a boat, AC power sources must only bind the neutral and ground while they're providing power. That means that when they're off, or serving as a pass-through for AC shore power, the ground and neutral are not bonded. My understanding is that most, if not all, inverters intended for generic use don't do this, which is both a safety issue and a potential corrosion issue on a boat. I'm totally open to hearing more thoughts on this.
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Marine AC sources need the Neutral and Ground bonded at the source. When connected to shore power the source is the main panel providing power to the pedestal. When using an inverter or generator, the source is the generator or inverter. When connected to shore power, the boat's AC system is essentially a big extension cord.
When connected to shore power the source is the shore panel providing AC, Neutral & Ground to the boat. Am thinking that calling the shore panel the main panel may confuse a guest if you are no longer in port while actually on the inverter and they had plugged in a heater.
Unless the guest is very knowledgeable, there is no need to tell them anything, except plugging that 1500w heater into the inverter will kill the batteries quick quickly, then they will be cold and without any lights or instruments. It is the owner's responsibility to keep the systems in order.
I have my heat pump and the electric element to my water heater wired into my AC panel so they can't run through my inverter. They can only be run if I'm either on shore power or running a generator. The rest of my AC circuits will run through my inverter. I have two separate control panels, one for DC circuits and one for AC circuits. That way I won't have any surprises...
dj
dj
The 50 A is an entirely new design that runs much more efficiently.
I discuss it a bit here:
Easy LiFePo4 Conversion - Marine How To
Easy LiFePo4 Conversion Before reading this article please read the 101 article on Drop-In's: Drop-In Batteries Be An Educated Consumer Hardly a day goes by where we don't see or hear
marinehowto.com
