Balmar regulator advanced programming (long)

[rbarkas]

I've been fine tuning the electrical system on our boat and I've gotten to the point where everything is working well. Now time to optimize.

My quest has led me to the Balmar 614 regulator. The default settings for a given battery type that Balmar uses are quite conservative. I've noticed that the regulator switches from bulk to absorption and then from absorption to float quite a bit earlier than I would expect, and also, no matter how long the engine is run, the batteries never seem to become fully charged. They charge to a point - let's say 85-90%, but then never seem to get any higher.

The regulator is set to the "FSB" battery type (Standard flooded cell). The batteries are sealed lead acid - 4 X 110AH. The alternator is a Delco 105amp heavy duty (continuous duty I believe) converted by a skilled local marine electrician to external regulation.

The default settings for this battery type are 14.4 bulk, 14.2 absorption and 13.4 float.

What seems to happen is that once the regulator switches to float mode no further charge current reaches the batteries. My shore power charger floats the batteries at 13.58 volts - with the shore power charger the batteries do reach 100% state of charge

There are 4 Balmar regulator settings that I intend to change:
1) FSB - Float voltage - from 13.4 to 13.6 volts
2) FbA - % of field current to allow switching from bulk to absorption...
from 65% to 55%. This setting is one of the params that the regulator
uses to decide when to switch from bulk to absorption.
3) A1c - Minimum time for absorption mode - from 18 minutes to 60 minutes
4) B1c - Minimum time for bulk charge - from 18 minutes to 30 minutes

I don't think that the slight increase in float voltage can hurt the batteries and I suspect that the other settings will act to reduce the total time to charge.

I've searched the net extensively looking for reports of other people tweaking some of the Balmar advanced settings but haven't found anything.

Anyone out there have any experience altering these (or other) Balmar settings to optimise charging system performance? Any thoughts on the changes that I've described?

[Maine Sail]

Originally Posted by rbarkas

My quest has led me to the Balmar 614 regulator. The default settings for a given battery type that Balmar uses are quite conservative. I've noticed that the regulator switches from bulk to absorption and then from absorption to float quite a bit earlier than I would expect,

Bulk and absorption are often timed with the 614 and other Balmar regs. You can change these values. A 14.2 absorption for wets is a little low IMHO. I would prefer a 14.4 for absorb and 14.6 - 14.8timed for 18-30 minutes. Check with your battery maker for max absorption voltages first though and remember that charge voltages need to be temp compensated especially when you get above 14.4V. A "timed bilk" means that once the terminal voltage gets to 14.6v it will charge at 14.6 volts for 18-30 minutes then revert to 14.4 volts.

Balmar is quite confusing with their terminolgy as BULK is normally not a "voltage limited" setting it is normally full fielding the alternator until it reaches an ABSORPTION voltage limiting set point. I prefer to think of it as a "double absorption" setting, high absorb and low absorb. Bul by all previous definitions BULK has been full field applied to the alt or max current not limited voltage. The marketing folks at Balmar though have tried to convince us otherwise though..

Originally Posted by rbarkas

and also, no matter how long the engine is run, the batteries never seem to become fully charged. They charge to a point - let's say 85-90%, but then never seem to get any higher.

Yes and cruisers have known this for a long time. Unless you run the motor for 10+ hours you'll rarely if ever get back to 100% state of charge (SOC). This is due to battery acceptance. The higher the SOC the less current the batteries will accept thus the last 15% takes a long time to put back in. Your shore charger has time on it's side the alt does not..

Originally Posted by rbarkas

The default settings for this battery type are 14.4 bulk, 14.2 absorption and 13.4 float.

I usually run wets at slightly higher voltages and am generally not a big fan of the Balmar factory "wet" settings but they are "safe" general settings.

Originally Posted by rbarkas

What seems to happen is that once the regulator switches to float mode no further charge current reaches the batteries. My shore power charger floats the batteries at 13.58 volts - with the shore power charger the batteries do reach 100% state of charge

There should still be some current flowing but at less than 2% of bank capacity. Your regulator should not be going into float from absorb until the batteries are accepting less than 2% of their 20 hour rated capacity. Ideally as a "sailor" you should never be even seeing float, unless just leaving the dock at full charge, or your using the motor way to much... Getting to float should take many, many, many hours, if not your going into float prematurely. Reducing voltage, which is pressure, also reduces what your batts will "accept".

Originally Posted by rbarkas

There are 4 Balmar regulator settings that I intend to change:
1) FSB - Float voltage - from 13.4 to 13.6 volts
2) FbA - % of field current to allow switching from bulk to absorption...
from 65% to 55%. This setting is one of the params that the regulator
uses to decide when to switch from bulk to absorption.
3) A1c - Minimum time for absorption mode - from 18 minutes to 60 minutes
4) B1c - Minimum time for bulk charge - from 18 minutes to 30 minutes

I don't think that the slight increase in float voltage can hurt the batteries and I suspect that the other settings will act to reduce the total time to charge.

I have seen many instance when the Balmar regs go into float way to early and charge slower than a dumb one as a result. A max of 60 min at absorption is very often nowhere near enough time at 14.4 to get a large bank charged so you may need to max out both "bulk" and "absorb" times if max is 60 min. You have to experiment with your bank though! If you go int float before reaching 2% of battery Ah capacity then your not holding absorption long enough.

Originally Posted by rbarkas

I've searched the net extensively looking for reports of other people tweaking some of the Balmar advanced settings but haven't found anything.

Sadly, most people, including many "pro's" install them and trust they are set right, very often they are not...

Originally Posted by rbarkas

Anyone out there have any experience altering these (or other) Balmar settings to optimise charging system performance? Any thoughts on the changes that I've described?

You really need to experiment with your installation. The best parameter to measure by is if you hit float before your current is less than 2% of the 440Ah capacity or 8.8 amps then your not holding the absorb voltage long enough. I prefer to set float to kick in for about 1.2-1.6% of bank capacity but this can be tough because if you start at 80% SOC and have timed settings well they will be different than if you start at 50% SOC.. Remember regulators have no clue as the current they only monitor temp, time and voltage so you'll need to mess with the time settings to dial it into your bank. Balmar regs try and determins SOC by comparing time at volts, time to get to volts, volts and field current but I have often found these measurements to be odd in the way they operate. Personally I wish Balmar just allow you to turn off float or adjust it to a max of 14.4V. If I had a dollar for every time I have seen a Balmar reg go into float before it is should... well....

Feel free to read this article about regulators.

Musing Regarding External Regulation

[Stu Jackson]

I agree with Maine Sail. If you read the manual, as you have, the critical issues are voltage and time.

Another way to put what Maine Sail about "cruisers know this" into perspective is that depending on an alternator to fully charge your bank should be discarded.

The reason is battery acceptance:

What I've seen, for example is this, from our Link 2000:

--- Return from a day sail, bank is down 15 amp hours, plug into shore power with our 75 amp charger, batteries will only ACCEPT 15 amps (360 AH house bank, they're pretty fully charged if only 15 ah down)

--- Most people will then assume that it will take an hour to replace the 15 amp hours at 15 amps of charge

--- NOT!

--- As the batteries absorb that 15 amp charge, they get fuller

--- The charge RATE goes down to 10 amps after 15 or 20 minutes and the bank is now down to 10 amp hours down

--- Now, it should only take another hour to charge those minus 10 amp hours at 10 amps -- assumption again; we're now up to an hour and twenty minutes to fully charge, right?

--- NOT again, because this keeps recurring

That's why a full charge takes a LOT longer that most people expect.

What goes OUT is easy, what goes BACK takes longer.

Please believe me, guys, because I see this all the time now that I have the Link 200 installed and working.

This is why people say the BEST investment for un-knowledgeable and knowledgeable skippers alike is to buy a battery monitor FIRST. Wish I did, because I'd been chronically UNDERCHARGING my house bank, even after all the spouting I do here and on other forums!

Believe it!

So work to maximize your regulator's performance in charging, but also remember that to fully charge your bank you'll need overnight shorepower. Use your alternator to work between 50% and 80 to 85% of SOC.

Main Sail also contributed this about acceptance: Battery Acceptance Observations - SailboatOwners.com

[Stu Jackson]

You may also be interested in this: Alternator Output Management with External Regulators [Small Engine Mode]

Depending on whether or not you bought the optional battery and/or alternator temperature sensors with your regulator.

I've found this very handy, as described in the link. Haven't checked Balmar's website (Welcome to Balmar DC Charging Solutions) to see if your model regulator has this feature. I just did. It looks like an "enhancement" of the 612 I have.

You might also simply select another one of the standard programs and voltages, and just change the times.

I agree, too, that I haven't heard of this before in all the discussions we've had about regulators. One of these reasons, I think, is that few people have gotten into the details as you have! Good for you!

But as mentioned in may of Maine Sail's and my discussions: IT All Depends on How You Use Your Boat.

If you're a marina hopper, this simply won't matter if you primarily use shorepower for extended periods.

If you want to stay off the grid, this "out of the box" thinking could be really helpful. So many folks don't understand that "defaults" on prgrammable equipment is just that, and can be changed. It's like our "infamous" Gotcha topic about the algorithms and defaults in battery monitors. See: Link-series Charging Algorithms -- The "Gotcha" Factor! You could do a search on "Gotcha" on this, co.com and our C34 Message Board and see the earlier discussions. If you're trying to emulate the performance of a shorepower charger and maximize your alternator output, you're on the right track,especially if you're really "off the grid." If you plug in after a few nights on the hook, doesn't matter too much, but could help. And, as Maine Sail said, solar would keep them up for you for periods you're not using the boat.

So, what are your use intentions?

[rbarkas]

Thanks Maine Sail and Stu - very informative material, just what I was looking for.

We recently returned from a 5 week circumnavigation of Tasmania - unfortunately we spent a lot more time motoring than we would have liked due to conditions. Most of our 'normal' use will be using the engine to recharge once (hopefully) per day rather than motoring for 8-10 hours a day.

Based on this hoped for once a day pattern and taking into account all of the info you've just helped me with, I think I'll change the regulator settings as follows:

Bulk voltage: 14.5 (still conservative but I worry about gassing the sealed batteries)
Bulk time: 1 hour
Absorption voltage: 14.4
Absorption time: 6 hours (Balmars max allowable)
Float voltage: 13.8

I was also very interested to see Maine Sails recommendation of fuses on the battery bank output. I've been wondering about that as I worry about what might happen to us and our poor boat in the event of something like a dead short inside the alternator or some similar mishap. I'm thinking about using a 400 amp fuse on the house bank and 250 amps on the start battery. The biggest legitimate load we could ever see on the house bank would be about 125 amps if the inverter is used without the engine running.

Thanks again for your help and info. I was aware of acceptance rate as a charging limit but the poor behaviour of our system (before tweaking) was kicking in well before the final 10-20% of recharge. I'll report back if any other useful info or more questions arise.

[Stu Jackson]

Maine Sail and I have been proponents of fusing the alternator output before it goes to the house bank, plus including a switch (or a combo breaker) to allow turning that off if the alternator goes wonky. One of my ftriends had that happen to him in Mexico and he didn't like "sparky" very much when he had to disconnect the fuse with 9/16" box end wrench! That's why a shutoff on that line makes good sense. I have one and have to install it on my boat. I have a Blue Seas mega-fuse there now.

Is your alternator output to your house bank or through the battery switch? How is your system arranged vis-a-vis the battery switches? 1-2-B or multiples?

[rbarkas]

Alternator is connected directly to house bank with a VSR to the start battery.

Separate switches on start and house. I just added a switch to combine the banks in the event I need to start the engine from the house batteries.

I'll now be adding fuses at the start and house bank positive posts.

I have a link 10 installed as well and I'll be reprogramming it to avoid premature assumptions about battery fullness.

[Stu Jackson]

Sounds to me like "You Got IT" --- all of it. Correctly, too.

Here's a handy dandy summary of much of what Maine Sail and I have been writing for the past few years.

Electrical Systems 101

[rbarkas]

Just thinking about fusing....

It makes sense to fuse the house bank at the point where the load is connected. Same for the start bank. I'm inclined to fuse both banks at 250 amps.

The third possible fuse is between the alternator B+ and the house bank. Yes, such a fuse would protect the cabling in the event of an alternator failure mode that included a short to ground. But if the fuse were to fail due to vibration or some 3 millisecond spike or some such then when the fuse blew it would in all likelihood take the alternator diodes out with it.

The question I'm pondering is whether protection against the alternator or alternator cable shorting to ground is worth the risk of a mechanical failure of the fuse.

If I do install a fuse between the alternator B+ and the house bank positive I'd be inclined to overspec it as much as possible - perhaps a 250 amp fuse on the 105 amp alternator.

[Maine Sail]

Originally Posted by rbarkas

Just thinking about fusing....

It makes sense to fuse the house bank at the point where the load is connected. Same for the start bank. I'm inclined to fuse both banks at 250 amps.

The third possible fuse is between the alternator B+ and the house bank. Yes, such a fuse would protect the cabling in the event of an alternator failure mode that included a short to ground. But if the fuse were to fail due to vibration or some 3 millisecond spike or some such then when the fuse blew it would in all likelihood take the alternator diodes out with it.

The question I'm pondering is whether protection against the alternator or alternator cable shorting to ground is worth the risk of a mechanical failure of the fuse.

If I do install a fuse between the alternator B+ and the house bank positive I'd be inclined to overspec it as much as possible - perhaps a 250 amp fuse on the 105 amp alternator.

Your alt is current limited and does not need a fuse at the alt end if you don't want one unless your wire is smaller in ampacity than the alt can deliver. If connected to the batt the wire should be protected to its ampacity rating close to the battery..

Fuses should be sized to the max ampacity of the wire and derated as such in engine spaces.