Next steps for the Alternator Regulator effort

[john61ct]

I think if it makes sense to ship with plain pigtails hard-wired, maybe terminate with a decent barrel connector, include a bit of heat-shrink tubing, and have a minimum decent crimper tool for that size available as an optional add-on purchase?

[hellosailor]

Anything that penetrates the moisture-proof enclosure is going to allow air and moisture to penetrate along with it. And of course, if the PCB extends through the case, there's a chance it can be impacted and cracked. Many laptops have had motherboard failures because the power plug penetrates the case and goes directly to a component on the motherboard, with no stress relief.

An unsealed case and conformal coating might work out better that way.

Conformal coatings, or sealed cases, or plastic cases, may all add a thermal problem. Generally regulators run hot (Balmar's potting being a known problem that helps kill them) so a heat-sinked case and mounting might be the better way to go. Bear in mind the regulator could typically be operating at 170F in an engine space, even with no load on it. Heat dissipation, biggest longevity issue.

[CarinaPDX]

I am not up on the current design. Generally I would want the PCB to be designed to fit in a "standard" plastic box. The Hammond Mfg. series 1591 and 1594 with standoffs fit 80mmx50mm PCBs with corner cutouts. It is fine to leave the purchase as an option. Some may want sealed boxes, or larger boxes with room for connectors. Or not.

Conformal coating is a mixed bag. Plain PCBs with a thin coating hold up well as long as salt spray doesn't get to them - otherwise all bets are off. My Denon car stereo survived 30 years (on a very wet boat), and was removed only because it was past time to upgrade from cassette to CD and HD radio. OTOH my Icom M802 SSB, thought to be in a safe location, got a dollop of salt water onto it and corroded the components on one corner. Like real estate what matters most is location, location, and location. Personally I would want to mount the regulator in a locker adjacent to the engine compartment, safe from most heat and all water (fingers crossed).

A terminal strip on the board would be good. Personally I don't like the idea of using RJ45 connectors - they are not nearly as robust as I would like. The most common problem is the little plastic catch that holds them together weakens and allows a physical disconnect (I have replaced a lot of plugs for this reason - paid for the crimpers a long time ago in rescued cables). For those who want a DeviceNet connector, a short pigtail to a terminal strip would work, as others have said, and simple to drill and mount on the case or run through a grommet.

Great project.

Greg

[Q Xopa]

My Alternator Regulator wish list
(much of this already available on your Alt Reg project)

• Separate Remote voltage sense, non current carrying, wire
• Fully programmable/ and customizable output parameters
• Selectable ‘No Float’ option
• Optional Selectable High Voltage Disconnect (HVD) relay control output connection,
• HVD controller output operated at either a selectable Voltage level increased to a programmable level or battery charge rate falling to a selectable value,
• Wireless/ wired or App and customizable also sounds nice
• Monitoring of some parameters. Perhaps as a ‘delux’ model option
• Dual customizable outputs for different House and Start batt banks. Maybe this could be another deluxe model option?
• Output reductions only based on max settable Alternator temperature, no time based
• Have a say min temp engine and belt, reduced Alternator output warm up period.

[Jon Hacking]

Originally Posted by CarinaPDX

...what matters most is location, location, and location. Personally I would want to mount the regulator in a locker adjacent to the engine compartment, safe from most heat and all water...

Many folks have mentioned putting these regulators in or near the engine room. I think this is very much the wrong place. They should be next to the batteries. The battery voltage and the current into the batteries are the critical things to measure. Each requires a twisted pair, and those leads should be kept as short as practical. The field, stator, temperature, power, and enable wires can be long without hurting anything.

Mounting these regs in or near the battery compartment keeps them cooler, and presumably dryer. So the boards should only need to keep moist salt air away, or a very light and very occasional splash.

I've been playing with these regs for a year or so. I bought my own cases, each with a pair of big wiring glands ... and found that trying to wire them up by passing wires through those glands was a royal pain in the patootie. And I almost never bothered to put the tops of the cases back on. Even mounting the boards on standoffs was an issue, as I had to mount the standoffs accurately to the case, mount the boards to the standoffs, then mount the cases to the wall, which made it difficult to get at the boards later.

It would be SOOO much easier if I could just screw the (potted?) board to the wall, and forget a case. The board is all surface mount components anyway, which are almost impossible to repair. Maybe solder 1m or so of each of the twisted pair wires to the boards first, as the rest of the connections aren't as critical.

I like the idea of pigtails with connectors on the ends, but would suggest that crimp on mating connectors be shipped with. The twisted pair leads should have screw lugs, so they can connect directly to shunts and bus bars.

[Jon Hacking]

Originally Posted by Q Xopa

• Selectable ‘No Float’ option...

Xopa, presumably you want this for LiFePO4s, as other battery types all benefit from a Float stage. What Al's regulators do for their LiFePO4 charge cycles is to manage the alternator so that NO current goes into the batteries after they're charged. This allows the alternator to carry on with house loads, which can still be considerable, without damaging the batteries at all.

[john61ct]

Originally Posted by Jon Hacking

Xopa, presumably you want this for LiFePO4s, as other battery types all benefit from a Float stage. What Al's regulators do for their LiFePO4 charge cycles is to manage the alternator so that NO current goes into the batteries after they're charged. This allows the alternator to carry on with house loads, which can still be considerable, without damaging the batteries at all.

Firefly Oasis are also best off with no float.

So exactly how, is the "NO current" into the batteries accomplished? Separate output to battery , a relay isolating the batt from House loads?

[Q Xopa]

Perhaps I wasn't clear, but what I meant by 'Selectable'. So it could be used for either Lead based chemistaries, (by selecting Float ON) or as is seemingly becoming more popular LFP, by selecting Float off.

The trouble for most chargers that we are trying to use on LFP banks is there is a float stage which isnt ideal for LFP. As we know there are tricks to get around this like setting Float votage lower than Absorption etc. If we could just switch that stage off it would be much easier.

[Jon Hacking]

Originally Posted by Q Xopa

Perhaps I wasn't clear, but what I meant by 'Selectable'. So it could be used for either Lead based chemistaries, (by selecting Float ON) or as is seemingly becoming more popular LFP, by selecting Float off.

The trouble for most chargers that we are trying to use on LFP banks is there is a float stage which isnt ideal for LFP. As we know there are tricks to get around this like setting Float votage lower than Absorption etc. If we could just switch that stage off it would be much easier.

Xopa, It sounds like you're used to relatively unsophisticated regulators. Al's regulators allow you to select what type of battery bank you have with much more precision than just a single switch. There are currently 8 preprogrammed battery types, 1 for LiFePO4 and 7 for different types of lead/acid chemistries (gel, AGM, sealed, etc) and 4 different bank sizes. Al has researched battery technologies pretty thoroughly. Acceptance and Float voltages are different for each type, and all parameters, including bank size, can be modified pretty easily if you don't like the defaults.

John61ct, one of the main features of these regulators is that they monitor current into the battery with a shunt, and make their charging decisions based on voltage AND current, where other regulators only use voltage and time. Since it's monitoring the current into the battery, it can easily drive the alternator so that it covers house loads but no current is actually going into the batteries. Nothing like relays or separate charging circuits are needed.

[john61ct]

Let me see if I'm any closer to understanding the details of exactly how this is accomplished.

So the output is put out on a common circuit (buss) carrying both the battery' charge input (measured with a shunt) and the current feeding loads.

When the shunt detects a low acceptance rate at Absorb voltage, showing that the bank is Full

presumably this endAmps a user-adjustable setpoint

then the regulator voltage drops to a lower Float, also user-configurable, let's say 12.2, which matches the battery's recently-fully-charged internal voltage if it were now isolated.

Correct so far?

To the extent a load device is online, it is "pulling" the current it needs.

The regulator is not regulating current, just voltage, if a say 60A load comes online, it makes sure the 12.2V is maintained so the load does not start discharging the bank.

The bank is never in fact isolated from the Float level current, we're just relying on the low Float voltage to prevent current from flowing into the bank.

Is all that correct?

I've never heard of an alt regulator actually dialling current up and down dynamically, so I imagine what you mean is that sensing bank acceptance is used as an input intp the process of regulating voltage.

[Jon Hacking]

Originally Posted by john61ct

Let me see if I'm any closer to understanding the details of exactly how this is accomplished.

John, great questions! There are a few things that should be clarified, so I'm goin to try to take it in sections.

So the output is put out on a common circuit (buss) carrying both the battery' charge input (measured with a shunt) and the current feeding loads.

OK, let's say there's a bus that's connected to the alternator output as well as the house loads, but between the bus and the batteries is a shunt that measures all current going into or out of the batteries.

When the shunt detects a low acceptance rate at Absorb voltage, showing that the bank is Full. Presumably this endAmps is a user-adjustable set point

Both correct. When the current required to keep the bank at the Acceptance voltage gets down to about 1% of the amp-hour capacity of the bank, the batteries are essentially full, and lead/acid batteries should go into Float mode. While you can set what you call endAmps, it makes more sense to set your bank size correctly. There are switches for 4 common bank sizes, and you can tell it your exact size if you want, but that's usually not needed, as that 1% is only approximate.

Then the regulator voltage drops to a lower Float voltage, also user-configurable, let's say 12.2, which matches the battery's recently-fully-charged internal voltage if it were now isolated.

I think you meant 13.2v, as 12.2v would be a relatively discharged battery, but otherwise this is essentially correct. Float voltages change for the different lead/acid battery types, and they're temperature sensitive, so the regulator compensates and uses different values as the temperature changes. You can change the Float voltage, but I'd be surprised if you need to.

To the extent a load device is online, it is "pulling" the current it needs. The regulator is not regulating current, just voltage, if a say 60A load comes online, it makes sure the 12.2V is maintained so the load does not start discharging the bank.

Again, I think you mean 13.2v instead of 12.2v. But the rest of what you said is how other regulators work. Al's regulator DOES monitor the current AND the voltage. So with LiFePO4 batteries in "Float" (for want of a better term) it drives the alternator such that NO current goes into the bank, and only house loads are generated. Voltage here is immaterial, but it tends to settle out at about 13.35v for LiFePO4.

The bank is never in fact isolated from the Float level current, we're just relying on the low Float voltage to prevent current from flowing into the bank.

I would not put it this way. I think the regulator works differently for lead/acid and LiFePO4 batteries, although I'm not positive. I think that lead/acid batteries are maintained at a proper, temperature compensated Float voltage, but LiFePO4s are treated differently, with active current monitoring after they finish their Acceptance phase. The ATMega64 microprocessor controlling the regulator makes this possible.

I've never heard of an alternator regulator actually dialing current up and down dynamically, so I imagine what you mean is that sensing bank acceptance is used as an input into the process of regulating voltage.

I hadn't heard about a regulator monitoring current as an input parameter either, so you're not alone. And yes, monitoring the current during the Acceptance phase is critical to deciding when the batteries are full and the system should switch out of Acceptance.

[john61ct]

Originally Posted by Jon Hacking

When the current required to keep the bank at the Acceptance voltage gets down to about 1% of the amp-hour capacity of the bank, the batteries are essentially full, and lead/acid batteries should go into Float mode. While you can set what you call endAmps, it makes more sense to set your bank size correctly.

Actually some batts spec at .005C, others .015C, LFP I would not go lower (higher SoC) than .02C

Some mfg spec no change in acceptance over an hour.

Yes meant 13.2V as an example "low Float"

Originally Posted by Jon Hacking

Al's regulator DOES monitor the current AND the voltage. So with LiFePO4 batteries in "Float" (for want of a better term) it drives the alternator such that NO current goes into the bank, and only house loads are generated. Voltage here is immaterial

OK, monitoring current is one thing, and a great thing wrt endAmps at the bank.

I was expressing doubt that the device is **regulating** current, I am guessing it only adjusts voltage, maybe many times per second to keep Float constant while carrying the varying loads' current.

As all VRs do, just with the shunt feedback loop being special.

And I'm not concerned at all with the canned presets, as long as all the charge profile setpoints are exposed for user adjustability.

[thomasow]

*Getting a bit sidetracked into specs, but there is clearly an opportunity for better communications. So with regards to the past few posts, yes the regulator is able to Regulate current. There are 4 concurrent PID regulation engines running simultaneously: Battery voltage, Battery Current, Alternator Temperature, and Engine load (watts). (Contrast this to only one regulation point in most regulators). Each of these PID engines are able to allow the advancing, or the pullback of the alternators field - impacting output. Of course, if the appropriate sensor is not connected – the related portion will stand down. e.g, if there is not a battery shunt then there is not current regulations, nor current based decisions – just traditional voltage and time. No (or failed) alt temp probe, falls back to blanket (configurable) field drive % limit.

In the case of using the active current regulations during 'float' mode, the regulator does actively regulate battery current. Vbat limit is still in place, but is used more as a safety backstop in case something goes wrong (Or, if the user has not installed current sensing, VBat regulation becomes the primary focus - just like all other 'regulators'). A 3rd option is to totally turn off the alternator output when in 'Float' mode.

"Float-as-you-like-it" if you will:

• Voltage regulation (like most all regulators today),
• Current regulation (Yes, active regulation of battery current - not just voltage)
• or Turned Alternator Off.

Your choice.


There are 23 parameters for the Charge Profiles, from target voltages, to current and temp limits, timeout values, current / voltage triggers and more. All of which are configurable if one wishes, and many of them may be configured to be disabled / ignored. My goal was not to tell the world: "This is how is MUST be done", but instead provide a flexible device which could be customized - especially important as new battery technologies come on line. And more so as we learn how to better approach these new technologies with no need to try to 'figure out how to get around' things for the desired behavior, just configure the Charge Profile for what you truly want.

But I also did not want to overwhelm most people by requiring them to set these 23 different factors. Hence the built in profiles selectable via the DIP switch. They were developed by surveying over 70 different battery manufactures & batteries for their preferred charge profiles and grouped into the default profiles. Another comment, I tended to be conservative with those built in profiles. Folks who want to do an aggressive Fast Charge (higher acceptance voltage) profile are able to via a custom profile, but the built in ones are more conservative.

There is more. To be honest, few if any of the 'features' I have noted folks asking for are not already designed in (outside of the App, but as you can see -that is being worked on, anyone want to help???) with the core regulation code being several years stable, the past few years have been focusing on communications.

OK - like I said, did not want to side track too much, but I do believe it is important for folks to have a clear idea of the capabilities already in place today as we talk about the Next Steps, which could well bring in new features!

[Jon Hacking]

Originally Posted by john61ct

... I was expressing doubt that the device is *regulating* current, I am guessing it only adjusts voltage, maybe many times per second to keep Float constant while carrying the varying loads' current...

John, you bring up great points. Actually, an alternator is a "current amplifier." The more current you put through the field, the more current comes out the output, with a gain of roughly 20:1 (dependent on many factors, like rotational speed). So regulating for current is actually very easy.

Battery voltage changes relatively slowly, depending on how much current is being put into, or taken out of, the battery. And it's voltage that can hurt a battery, so that's what all regulators monitor. But actually, all regulators change the voltage by driving more or less current into the battery. Alternator regulators can't change the voltage directly, they can only modify the current, and it's the current in/out that changes the battery voltage.

[john61ct]

So in the case of an already Full bank (as per shunt endAmps), FloatV set to say 13.7V (higher than batt resting V)

and varying-amp loads coming and going

your VR is (can be set to) constantly adjusting current output to service the loads while ensuring "no" current is being accepted by the bank?

_____
Or, if the goal is to completely isolate the bank once Full, can a relay be triggered to do that based on reaching endAmps?

Assuming a buffering load dump (e.g. cheap lead Starter batt) is still available.

And can a "pre-shutdown" event be configured to close that connection before the engine gets turned off?

Thanks very much for the education, sorry if it's a derail