Great thing about the field effect ammeter is one can relocate the sensor easily. No moving the shunt, or cables required, just unbolt cable slide off round sensor and move to another cable.
Can also put it on the (+) cable, which is how mine is presently working.
Mine is still reading total alternator output, but at some point I will move it to read amps into or out of the battery(I already have this displayed elsewhere, not visible from driver's seat), with the display on dashboard, next to my 3 wire voltmeters, next to my turns counting 10 turn bourns potentiometer which adjusts the vehicle's voltage regulator to what I determine is best for the battery at that moment.
Yes, than maniacal laughing you just heard way off in the in the distance, was me.
My existing door seals, when i cleaned them, My finger kind of ripped the interior pleating on the outside. I've not really examined how the seals are held in place on the door, but no doubt it should be replaced for better performance.
I think a secondary seal inside the original would keep the metal fridge box skin from being in direct contact with the coldest air inside, and negate the need for replacing the torn original seals, which still appear to seat tightly and would easily pass a dollar bill test.
The Milk freezing episode on my regular setting just got some wheels turning with an eye on efficiency improvement, although I can obviously get away without any more effort. The hyper ventilated Danfoss db35f compressor is in yawn/cruise mode at 2000 rpm and a 1.8 cubic foot box.
It is just the door is the weak link and the only area where improvements could be made.
I recently turned my 1.8 cubic foot Vitrifrigo c51is 12vDC compressor fridge off, defrosted it, cleaned and fluffed door seals, left door open for 16 days.
On restarting it, I set it to my usual spot on the dial, about 2.8 of 7, went shopping, placed a gallon of milk inside at 7:30 pm, and the top of it was frozen in the morning, despite also putting in a half gallon of warm tomato juice and some other things grocery store cold at the same time.
Usually, this setting does not allow freezing of things in the box.
I hypothesize that the cleaned, fluffed, not compressed for 2+ week door seals sealing tighter, contributed to this unintentional partial freezing of some items within. Looking at door seal, which is not really in good condition, It appears as if I could add another seal inside the current one, and have it rest on the interior plastic, instead of the metal of the fridge box on which the current seal seats. This seemingly would vastly increase the effectiveness of the air seal, but also keep the warm exterior metal box of fridge fridge from being in direct contact with the inside, across the seals width, conducting heat inside the box.
Anybody ever considered upgrading the seals on their fridge, not just replacing original, but adding an second seal inside, or perhaps outside, the original?
I've got much added extra insulation on the other sides of the fridge, and a very well ventilated condenser, but the door itself is lacking in thickness and the door seals are not what they were new, and I believe the design is a bit inefficient with metal from fridge body wrapping around to inside the door seal, conducting heat inside.
I believe much room for improvement exists here and would reduce battery draw and extend battery and compressor life. I have a solid area on the door and a flat mating plastic surface inside the current seal for adding another seal.Guess I could replace original seal too.
Just got to get the right amount of compression I guess as well as cut perfect 45's at the right length and glue edges together.
The screwy31 is a 12v group31 USbattery, and I can say the 15.3v finishing/absorption voltage, was key to keeping the specific gravity walk every cycle down to a minimum when cycled deep, daily.
14.7v was a joke and Specific gravity would tank if all it got each day was a few hours of 14.7v.
The 12v battery in that link says a 15.5v absorption voltage! And only 15.6v equalization.
Now a word from out resident USBattery nemesis......
He might start sputtering something about Herb Tarlick and paisley ties :)
For nearly 18 months, I have had only the one 90Ah Northstar AGM battery for both house loads and engine starting. The location underhood where engine battery is supposed to reside, is empty.
This battery has no issues cranking my engine at 65Ah from full. I am not sure of my plan in the future. I was thinking about a small 16 or 18AH Odyssey AGM battery just for emergency jump starting and a possible portable 12v battery, but I thought that a year ago and never bothered.
The Odyssey can handle huge charging amps too.
I would like the t-1275 for PSOC cycling on solar only, if I were to be less mobile, or did not have access to grid power for plugging in MeanWell. In my experience, the NS AGM is not happy without high amp recharges every so many deep cycles.
After figuring out the screwy 31's charging sweet spots, the Northstar AGM is easy. Just hold absorption voltage until amps taper to 0.XX amps, to determine full, and when possible high amp recharge it from its most depleted state. That is key to its performance, in my observations.
The screwy 31's amp taper at absorption voltage had very widely swinging Specific gravities. I found it much harder to finesse the screwy 31 to 'full' but honestly 'full' only happened after 45 minutes at 16v and then SG each cycle thereafter dropped a little more with the 14.9vABS and 15.3v finishing charge regimen.
The NS Agm is likely in the 450 deep cycle range (under 60% SOC) with several hundred shallow cycles and several thousand engine starts.
Perhaps when it is due for replacement, the firefly carbon foam AGMS will have been more battle tested, or I will get 100Ah of Lifepo4 prisimatic cells. Honestly another Northstar would be great too, as this battery has impressed me since cycle 1.
Anybody have a link to the nifty shunt/voltmeter mod for the Megawatt? I can't find it on Ebay.
Not sure what you want, An Ammeter?
No shunt required with this ammeter:
I have a GTpower meter on my Meanwell output, but I modified the leads to 8awg( from 12awg) so it can handle 40 amps continuous without heating excessively.
Modifying these with 8awg is not too hard, but I did destroy one with a solder bridge.
Another wattmeter clone comes with 8awg leads but proved to be a huge disappointment as the Wh and AH figures were inaccurate in extreme.
As far as modifying the MW for a larger 10 turn voltage trim pot, Mexwanderer/Mrwizard are in the process of doing a pictoral/write up on the process.
If a Megawatt stays at full output for an hour this is no stinky bueno.
I use my Meanwell rsp-500-15 as a bulk charger, absorption, float charger.
At its maximum output(40 amps), it does get hot.
I have enhanced airflow through and over unit, and added more heatsinking and can usually keep it below 120F at maximum output.
I believe Mex's quoted words above are not only to indicate 3 stage converter X is likely to drop to float, or to a lower absorption voltage( thus slowing charging) while the batteries could accept 36+ amps, but that the Megawatt at 36 amp output for and hour might overheat the unit.
Those considering using these as a bulk charger, not just as an Absorption charger to take over when the converter decided to drop voltage while generator is still running, need to consider increasing heat removal from Megawatt/Meanwell to promote longevity, especially in hot ambient temperatures.
I have a thermocouple on the inside of my Meanwell on a heatsink. Ambient temperatures have a Huge affect on internal temps. At 70F it rarely exceeds 106f at 40 amps output. At 90f it will easily climb to mid 120f at 40 amps output, and that is with extra fans and more heatsinking, and airflow over the whole unit.
Once amps drop to less than 32 the heat the Meanwell makes is back down below 100F. Those 8 extra amps really cause a lot more heat.
My original cheapo xtra gritty 10 turn 1k ohm pot I bought for cheapowatt and transferred to Meanwell developed weird spots mid range which would cause overvoltage clicking to occur in Meanwell.
Faderlube f5 fixed it, temporarily
That pot had 3 screws holding a cap on which allowed the f5 to be sprayed inside easily. Do not think that is possible with my newer 10 turn Bourns pot.
F5 might have to wick down the rotor
Have a reason for the ambivalence toward Deoxit Gold g5?
Cell phone micro usb connections 'should' never require the aggressiveness of d100.
Gold's description seems perfect for a micro USB connector.
DeoxIT® Gold (formerly ProGold), is a unique conditioning solution that improves conductivity and provides long-lasting protection on gold, base metals and other precious metal contacts and connections (gold, silver, rhodium, copper, bronze, nickel, etc.).
Use on plated connectors, contacts and metal surfaces for maximum performance and protection.
Recommended for critical applications where only slight cleaning action is necessary. If the surface looks clean, applying DeoxIT D-Series contact cleaner first is usually not necessary. DeoxIT® Gold is designed to dissolve small amounts of oxidation. Apply DeoxIT® Gold after DeoxIT® D-Series contact cleaner on plated metal surfaces, except where noted with DeoxIT® Shield S-Series below. The more critical the connection or part, especially low current applications, DeoxIT® Gold should be the final step.
For reference, DeoxIT® Gold has approximately 0.5% cleaning action.
BTW the link I posted in previous post is for a sub 2$ plug in wall charger for a Samsung s3 battery which has been removed from phone, as it seems the failure of the microUSB receptacle in the phone, is a given, the only variable is the time/ insertion removal cycles to failure.
and the amount of leverage applied to plug during its life.
I flew 2518 miles for Turkey. Last night My Samsung S4 mini decided she no wanted to charge battery. I noticed at 22% SOC.
I had USB power meter with me, It showed 0.00 amps. My other USB devices worked normally showing expected amperages. I have been careful with micro USB receptacle, It does not appear loose. Micro USB cables tight, quality, cared for, blemish free. Magnifying glass reveals nothing obvious.
Deoxit gold g5 lubes/cleans/refreshes terminals somewhat regularly..
It appeared phone just did not want to charge battery.
Soft reboot. nothing
CAshe delete reboot. nothing.
COnnector wiggle finesse, no change at all.
It made the plugged in/ charging sound. The battery icon had the lightning bolt through it indicating charging, but percentage screen crept downward. USB meter showed 0.00 amps
Flight day after tomorrow.
Am Used to using phone as boarding pass. Music at proper volume through headphones mostly obscures screaming children. Printing boarding pass in sister's house could prove a tool throwing curse fest. I Don't check bags, right to security, don't want to print at airport.
Batteries + stick and brick. Overpriced duracell replacement in stock. Check for charging in store. No charging, but employee's Samsung phone showed 1.21 amps. Kept overpriced battery (42.59$) for travelling, turned off phone, but forgot to press OK/Cancel after turn device off.
Drove back to sister's. Plug in phone, presented with cancel/OK screen. Pressed cancel.
Look at USB meter. 0.98 amps flowing.
Who freaking hoo!!
I will be purchasing an wall plug in style external battery charger for $8.49 for when it happens again. Can't really buy one in any stick and brick.
If you come a bit NOB next time, Deoxit Gold G5 awaits your s3 micro USB terminals, after d5 of course, if required.
I know most of this conversation is about bulk charging, and keeping maximum amperage flowing for as long as possible to reduce generator run times, and whether AGMS are any better than flooded in this department.
While I have a battery monitor, I trust it less and less the more cycles that have accumulated either without the high amp recharge, and/or the incomplete recharge, say getting to 95% instead of 100%
Many successive 95% recharges then require a very long time for amps to taper to 0.4a at 14.7v. I've seen it take 3.5 hours to taper to 0.4 amps once 14.7v has been reached at 40 amps initial bulk current. After many PSOC cycles and low and slow solar only as the charging source, then plugging in the meanwell, I've seen it take 10 hours for amps to taper to 0.4a after it first reached 14.7v.
When many PSOC cycles have accumulated, at least on my NS AGM, the progressive capacity loss, or temporary sulfation, or whatever term one is comfortable with using, not only means that a true full 100% recharge/ recovery, not only takes longer, but amps begins tapering sooner as well. I've been quite surprised to see the battery still 35Ah from full and reaching 14.7 at only 27 amps. Usually this is more like 22 to 24AH from full when amps start tapering at 14.7v.
I imagine if one were relying on generator only, no solar, that 50 to 80%, even if 80 is not really 80% anymore, takes longer and longer to achieve, the more partial state of charge cycles that have accumulated.
I really try not to go that many cycles without either the 100%, and this usually requires alternator or meanwell contribution, which also means no less than 40 amps initially. My battery craves the high amp recharge. Ideally, in my observations, it would get 25 to 40 amps from its most depleted state, every recharge. It is not happy with low and slow solar only, and I determine this by voltage held under load for AH removed the next discharge cycle and the one after that. This behavior is predictable and repeatable.
As my battery monitor is usually at my right elbow, I check it often each recharge and discharge cycle, and likely have much more trends and tendencies data than most here. In the future, if/When I decide I require more capacity, I am torn between getting another AGM or t-1275, as I love the no amperage limitation on Northstar or Lifeline or Odyssey AGM's. I love the high CCA, the no watering, and seeing 12.7v on a 90AH battery when the screwy31 at 130Ah capacity would show 12.4v at the same level of depletion under the same loads, fills me with warm and fuzzies.
Only caveat is the AGM I will use, requires the high amp recharge after so many cycles, to remain healthy and full of grunt and would not be a good long term solar only recharge battery.
Whether the Amperage limited AGMS are more suited to solar recharges, is unknown to me, but It is incredibly obvious, how much better my AGM performs after a high amp recharge, and recent battery temperature data also makes it obvious the battery does not appear to perform better, just because it is hotter from thre high amp recharge, as the next night 24+ hours later, when the battery temperatures have returned closer to ambients, performance is still increased despite the likely low and slow to 98% having not completed the job the next day.
The time it takes amps to taper to the required level to consider an AGM 100% charged, increased with PSOC cycling and battery Age/overall cycles accumulated. In wintertime, My 200 watts of solar needs to achieve absorption voltage on my 90AH AGM by 10:30am, or there is no hope of 100% happening that day without pluggin in and letting the Meanwell finish the task.
My observations on my Northstar AGM-27 battery, indicate that how many amps the battery can accept depends on how many cycles it has gone without a full charge, or without a high amp recharge.
Lots of low and slow recharges until 92% and then if 40 amps are then applied( to a 90Ah battery) amps will start tapering much faster than if the day before had a high amp recharge until 100% was achieved.
I don't really have the data to compare to a flooded battery, not in any scientific manner anyway, but the screwy31 ( 130AH)had no issues accepting 40 amps for quite a while when depleted.
At which point in the SOC that amps started tapering at 14.X volts, compared to the AGM is not data I have on Hand.
And as i do ot ever use a generator, how I recharge is not as important as to someone doing successive 50 to 80%. I Aim for no less than 95% and 100% every 5 cycles.
So how much partial state of charge cycling has been going on, in my opinion, will have huge impacts on when amps begin to taper when held at absorption voltage, and this makes direct comparisions of the AGM vs Flooded in the bulk phase, unwise.
No doubt a test could be set up that would be valid, for that particular AGM brand vs that Flooded brand in X type of use/ charging regimen, but a flat out statement that AGM always charge faster given the same amperage charger as it takes longer to reach absorption voltage, has dozens of qualifiers for it to actually be true anrf repeatable.
But just the fact that when new and healthy an AGM has less resistance, means it will be able to charge faster, if the amperage is there to do so. If the charging source cannot instantly achieve absorption voltage is not there, amps will likely start tapering a bit later on the AGM, and perhaps one could shut off their generator sooner than the guy with flooded jars of the equal state of health and the same number of PSOC cycles accumulated.
the original purpose of 12v plugs, was to get hot and light cigars or ciggarettes.
Too bad the 12v plugs now get nearly as hot passing more than 60 watts to modern devices,
The ciggy plug connector/receptacle, is a crime against DC electricity.
Keep house battery out of alternator loop for testing
What is engine battery voltage with engine running?
Perhaps your alternator's Voltage Regulator is only allowing 13.2v.
Perhaps it fried a diode or 2 and is only working on 1/3 or 2/3rd capacity.
Can't one check for AC voltage to determine a failed alternator diode?
If the Alternators voltage regulator is allowing more voltage than either battery, there will be no backfeeding going on when driving regardless of resting voltage differences between engine and house battery.
Thanks for bringing the cooler weather to florida, even Temporarily.
I've been using the Meanwell rsp-500-15 for 2 years now as my exclusive plug in charging source, and my scorn for automatic charging sources has only grown in intensity since.
While it is rated for 500 watts, it regularly surpasses 600 watts when the battery is depleted enough.
I employ 45 amp anderson powerpoles to disconnect it from DC when not in use.
When I unplug the 120vdc but it is still connected to DC, there is a click as the overvoltage protection kicks in.
Or if I lower voltage faster than surface charge depletes I will hear the same click.
The rsp-750-15 and -1000-15 have features that the rsp-500-15 does not. The desire for 1000 or 1500 watts suggests to me this will be used not just for top charging but for bulk charging and the OP asked about 50 to 80% charging.
When Maxed out, my rsp-500-15 makes a lot of heat. The very high rpm 40mm fan is very loud. I added more fans and heatsinking to keep this fan from coming on at lower amperage outputs, and to extend its life. I would recommend additional airflow aimed over meanwell casing, for use when maxed out charging depleted batteries.
Perhaps add some of these to meanwell casing for additional heat dissipation:
My voltage range on the rsp-500-15, with a 10 turn 1000 ohm bourns potentiometer, is 13.12v to 19.23v.
While I intended to use a wind up timer, I have never bothered installing one. But if I did, I'd want a 6 hour timer, as 4 hours would have the unit shut off early as my AGM battery takes no less than 3.5 hours for amps to taper to 0.5% of capacity once absorption voltage has been reached( usually 25 to 35 minutes at 40 amps), and with many partial state of charge cycles accumulated, can take much longer for amps to taper to 0.5% of capacity at absorption voltage.
I thermoepoxied a Ktype thermocouple to my alternator's Stator casing.
I wish casing temps were more indicative of rectifier temps.
But my data with this thermocouple location shows the alternator casing heats excessively only when not moving and at or near maximum output.
At 65MPH and 80 amps output the casing averages 109f.
Idling hot at 54 amps output and that 109f increases to 160F in under 2 minutes.
Driving 25mph at low engine rpms also causes the temperature to rise quickly.
My observations indicate alternator casing heat is of course dictated by load, but also by airflow not only caused by more rpms spinning the alternator fan faster, but by underhood airflow.
Underhood airflow is a big variable vehicle to vehicle.
How representative of actual rectifier heat, vs the casing heat is, is unknown to me. Guess i could run another thermocouple to (+) output stud to better represent rectifier heating.
Right now I only have 90AH of agm battery, total, and have to rely on lights and blowermotor on high and other electrical loads to keep the alternator maxed out for these tests.
I once considered making a cold air intake to feed my alternator. Easier was to install a simple heatshield between alternator and nearby exhaust manifold and this seemed to increase hot idle speed amperage by about 5 amps.
My neighbors bought a new residential fridge for their stick and brick, and it was a perfect fit in the receptacle.
However the fridge instructions said 2 inches of space was required over the fridge, and 1 5/8 between back of fridge and wall behind fridge. They had only 1/4" under a cabinet basically enclosed the whole top of the fridge.
I warned them this would cause the fridge duty cycle to increase a lot, but they really liked how it looked, being such a tight fit.
I said lets throw it on a Kill a watt, and My IR gun showed 120 degrees( 72 ambient) above and behind fridge within an hour of plugging it in.
The IR gun readings alone were enough to make my point. I modified their cabinet above fridge with a false back and opened up the cabinet so the fridge could breathe properly. The Kill a watt readings were not recorded before and after cabinet modification, though I do wish I had collected that data. Temps after venting cabinet above fridge were rarely over 92f in ~70F ambients.
My small DC compressor fridge can vent to RV exterior, or interior, or both. Venting condenser heat was a priority in designing the cabinet in which it is installed. One 80mm cabinet exhaust fan runs 24/7.
One can easily wire a 12v fan and it need not even cycle on and off with compressor. The Noctua NF-f12 moves 53CFM for 0.05amps and is very quiet. This minor electrical consumption will be negated by the lower duty cycle of the fridge, and decrease the time required to remove the heat from warm items placed within.
Premature Norcold DC fridge compressor failures of the 90's and early 2000 are attributed to improper installs where condenser heat evacuation was not a consideration of those installing them. The heat removed from box and generated by compressor motor, has to go somewhere. The better this heat can be transferred to atmosphere, the less energy it will use to maintain sub 40f temperatures inside.
You don't start the equalize voltage from a partial SOC
You don't do it, unless the batteries are already fully charged
I am surprised 40 or 50 xantrax amps can actually get the 2? GC-2 depleted batteries to 16 volts in what 'appears' to be within an hour or 2 time frame.
My single 90AH AGM battery when depleted can take 40 amps for 30 minutes before absorption voltage is hit. It then requires a minimum of 3.5 hours before amps taper to ~0.35a at 14.7v which is generally considered fully charged.
The battery needs to be held at absorption voltage for a period of time before pushing it to 16v for an EQ cycle.
Sounds like the batteries are really on their last legs, and new ones are in your future, but the new ones will not appreciate being pushed past 14.8v when less than fully charged either.
The hydrometer will reveal a lot, so would an ammeter. Voltage readings alone without knowing how many amps at that electrical pressure, are flowing, can be very confusing and not indicate much at all.
Some residentials place the condenser on the fridge's side walls, instead of having a finned visible heatsink one can easily vent.
Besides extra insulation, proper venting of condenser it the best way to increase efficiency, and also the easiest way to ensure poor performance if not vented properly.
Mine DC compressor fridge sucks coolest possible filtered ambient air and pushes it only once through condenser, across compressor and controller then out of the fridge cabinet entirely.
Even if the control of current flow into house batteries were Ideal, one's house batteries are still at the mercy of the vehicle's voltage regulator which is more concerned with not overcharging a single barely discharged engine starting battery.
Most people take a voltage reading once at idle and will proudly declare my alternator puts out 14.2v, but the sad fact is the voltage yoyo's all around with load and rpm, and is never ideal for proper recharging of depleted house batteries.
UNless of course one can control their vehicles voltage regulator.
My VR was in my engine computer and would choose 14.9v, or 13.7v and very rarely 14.1v. it would decide 14.9v when the batteries were full, and 13.7 when they were not, and 14.1 just to screw with me.
With Mex's help, I now decide on the vehicle target voltage with an adjustable regulator to Which I added a remote potentiometer to and mounted it on my dashboard next to 3 wire digital voltmeters. 3rd wire is voltage sense.
Amazing, well not really, how many more amps flow into depleted battery, when I choose 14.7v, compared to 13.7v.
Alternators with internal voltage regulators can be modified for external regulation. Balmar makes 3 stage voltage regulators with adjustable setpoints and durations and all sorts of bells and whistles.
I find twisting a potentiometer dial located next to a voltmeter to release more serotonin than a 700$ voltage regulator ever could.