Getting Ready to Go

Thursday - Another cool-ish morning at 51°F@10:30. And, I think there is more rain in the forecast. Everyone says that it's colder than usual but everyone seems to say that. I stayed inside for the morning test session. 53°F felt too cold to be sitting outside. 

The paranoid me started the engine this afternoon. Since we are scheduled to leave on Sunday, I just wanted to make sure that the engine will start. It started fine with minimal smoke, though it still smelled like an old diesel. I guess there is no getting away from that. I also checked and filled up the tires on the RV. The last time the RV was driven was when the ambient temperature was 100°F. Now, it’s 55°F and the front tires were a bit low. The little pump took quite a while to get the front tires up to 110psi which registers as 115psi on the pump. I’m not sure which one is correct. Probably neither. 

Friday - Another cool, partially cloudy day. I think the high was in the low 60s (°F). I participated in two test sessions today and worked a bit on the battery heater. The switches below the temperature controller are for the battery heater, battery cooling, and to enable engine charging. The second temperature controller for cooling is not installed. It will simply control a fan to exhaust warm air from inside the box outside. 

The temperature controller for heating is set to turn on at 5°C and turn off at 7°C. I don’t have the silicon pads installed under the batteries but I do have one hooked up and the thermocouple between the two batteries just in case the heater is accidentally turned on.

Saturday - Just about everything is put away. Shortly after taking this picture, the awning was stowed and the kitchen slide went in. I also put in the living room slide as I needed to try out some slick hard plastic floor glides where the slide touches the floor. I think they’ll work but we’ll find out tomorrow at our next location. 

Returning to the RV

Monday - We left West L.A. around 9am with very little traffic until we were ready to leave the basin. A lot of people escaped the crowds towards the desert and AZ. We stopped just west of Yuma and visited with friends, Tom and Lori, at their boondocking spot. It was a short visit but we haven't seen them in over 3 years. The last time was in Bakersfield. We arrived back at our RV around 8pm. Not too long of a trip but I was really tired so Bridget did most of the driving. I drove out of L.A. as that was really familiar. 

Tuesday - Time to unpack a bunch of stuff for the next few days. We will be leaving here on Sunday. When I first arrived on September 1st, four months in one place seemed like a really long time. But, with all of the projects and old/new friends, time has passed quickly. 

Wednesday - The nice weather didn't last long as it is raining and only 51°F right now. I just finished a test session this morning. 

Later - I had played around with the Magnum charging parameters again. Lowered the absorption voltage to 14.2V from 14.3V and the rebulk to 13.0V from 12.9V. So now it cycles between ~90% and 98% SOC and there are no longer long periods of 90amp charging. This is not suitable while being plugged in. It may work better if I had the Magnum battery monitor but not for an additional $170 or so. This would be another shunt installed on the negative cable with a run to the battery bank positive and negative posts for more accurate battery voltage. Right now, the voltage is measured within the inverter/charger so it is influenced by load. 

The good news for today is that the hot tub is working again. I guess it’s been broken for about a week. Fortunately, for me, it was the week we were gone.

Merry Christmas

Sunday - We are still in West L.A. today and plan to head back to AZ tomorrow morning. We’ve had pretty nice weather while here though the nights are cool. We spent the day with Bridget’s son, his wife, and her family. Lots of delicious Filipino food as well as my traditional turkey, dressing, and cranberry sauce. 

Plus, Spam musubi as an appetizer. We had a fabulous time and way too much food…

Tomorrow, we head back to AZ.

Road Trip - Part 2

Thursday - The view from the hotel this morning. Not too bad. I expected a bit more snow on Mt San Jacinto as it’s about that time of the year. And the wind turbines are mostly still. A few of them are slowly turning so I guess that means not much wind right now. 

We went to a place called Tender Greens in Culver City that my cousin recommended. It was delicious. Arugula salad, garlic toast, grilled veggies, and a small grilled steak. Just the right amount for dinner. I picked up some groceries for Christmas dinner at David and Alexa’s home near here. Kind of my standard holiday meal. Sous vide turkey, dressing, and cranberry sauce. Plus, I brought the stuff for Spam musubi. 

BTW, I just noticed that the iPhone lock screen shows my current location. Interesting to what it shows when I’m in Alaska…

Friday - A quiet, non-traveling day. We visited a bit with my cousin yesterday here in Culver City. Right now, we are at a dog park with Bridget’s son, David. We had lunch at a plant-based restaurant called Monty’s in Culver City. 

Later - We picked up my middle son, Kenji, in downtown L.A. i.e. right in the middle of the city. Why he chooses to live here is a mystery. We are taking him shopping to pick up essentials such as socks, shoes, etc. plus some kitchen items. Stuff that he probably wouldn’t purchase himself. We went to a Target and Ross for Less (clothing store) kind of near USC. We then went to a mall to look for shoes but he couldn’t find what he was looking for. 

Saturday - Today is being spent at Bridget’s sons home in Culver City. I’m cooking for tomorrow and they are playing board games… I’d rather be cooking. Turkey in the sous vide (24 hours cooking time), cranberry sauce made, and making jook (congee) from the turkey bones. Before vacuum sealing the turkey, I cut the meat from the bones. I’ve never made jook before. 

The jook turned out fantastic even without the ginger and spring onion garnish. I just used furikake and a little soy sauce. 

Road Trip - Part 1

Tuesday - I tested the temperature controller with the 24watt silicon heating pads. I think these should work fine. I initially tested the controller around ambient temperature with a shutoff temp of slightly higher. I then held the thermistor and it shutoff in seconds. I think these Amazon bargains should work fine. Total of $31 for two controllers and four heat pads. (Spare parts!). 

Wednesday - This morning, we headed west towards California. Our destination for today is Palm Springs which makes tomorrow’s trip into (and through) L.A. much shorter. Todays trip was just over 400 miles with Goggle routing us on a southerly route before heading north west of the Salton Sea. 

Dinner was at Sherman’s Deli at the suggestion of Brian and Michelle from LivinRVision YouTube channel. They said that this is the pie that all others are compared to. We’ll see…

BTW, the pie was not dinner.

Quiet Weekend

Thursday - Last night, it dropped below freezing by a couple of degrees. Enough that the heat pump switched to the furnace. Not much happened today. A test session, then some minor wiring to add in the second circuit breaker to the DC-DC charger. The Renogy recommendation is for a 60-amp breaker on the input and a 50-amp breaker on the output. 

Bridget went out to the arboretum with a couple of friends so I’m trying out another Chinese restaurant. Ba-Dar on Broadway is just about a mile from the park. I had the sizzling pepper beef. It was delicious. And the hot-sour soup was far better than any I’ve had in the last year or so. Definitely, the best Chinese food I’ve had in Arizona. Most Chinese restaurants we’ve tried were sub-Panda Express (which isn’t bad).

Friday - I finally finished the DC-DC charger. There is a trigger wire which would usually be connected to an ignition wire to turn the charger on. I opted to connect it to the trailer tail light circuit just like the auxiliary radiator fan. This way, the charging circuit won’t be loaded until we drive down the road. I need to pick up more 16AWG wire as I seem to have used up my supply. 

Saturday - How about that. Three days without any HomeAssistant screenshots! I spent the afternoon putting things away that we probably won’t be using before our upcoming road trip. Such as the bikes and Blackstone. Plus, I’m keeping the old 2/0 battery cables and the half sheet of foam insulation. I’m storing it under the folding table where I used to have plywood pieces. 

I dug out the iPad to upgrade the iOS to the current version. It’s been month since I last used this device and now I know why. The battery runs down fast. When I picked it up, the battery was at 92% and it’s already down to 88% after ten minutes of use. The battery was supposed to last a long time.

Sunday - Still trying to use the iPad. Overnight, the battery dropped down to 75%. I have the Mac on the campground WiFi trying to do and OS upgrade. And it says about 4 days remaining, Not very encouraging.

Otherwise, not much going on. I’m at the hot tub right now. Definitely the best amenity at this park. It has been really handy for doing projects especially with Home Depot just a short walk away. 

Misc plus Kartchner Caverns

Tuesday - After morning coffee and doughnuts at the clubhouse, I met up with Jerry and we installed a 12V led light strip below the basement storage bays doors. He had an AC led light strip before and the 12V one can be left permanently wired. We added a shutoff switch and are wired into the lights for the storage bays. They look pretty good. I think I want to do this mod as well.

I think that things are working just fine. The batteries discharged for most of the night and around 7am, bulk charging started for about an hour. Then solar charging kept the batteries fully charged until mid afternoon. Lots of clouds today. 

Since the Victron solar controller uses the battery monitor for voltage, it’s actually set up simply using the LiFePO4 recommendations. No monkeying around trying to get it work properly. 

Wednesday - Below freezing! What happened to the warm 70°F weather?

Today, we went to Kartchner Caverns for an 11am tour with Lynne, Jerry, Mike, and Kathy. We had taken the tour several years ago and it was just as good again. Here is a picture from a Google search as no cameras, cell phones, and any other devices, are allowed inside the caverns.

We then went to a microbrewery for lunch. I had a Navajo taco. Lunch was wonderful as was the company. 

More Monitoring…

Sunday - I’m still closely monitoring the charging from the Magnum inverter/charger. Ideally, it won’t charge the batteries to 100% every time while we are connected to shore power. I have been adjusting the absorption voltage, absorption time (aka CV duration), and rebulk voltage to get the profile that I think would work for us. I initially started with the BattleBorn recommendations. It made a good starting point. Using their settings, both batteries would reach 100% and their BMS would disconnect from the charging source. So, I would turn off the charger, discharge the battery and turn down the absorption voltage. This is the voltage that the Magnum switches from CC to CV. The charging mode shows on the Magnum remote display. 

Right now, it’s set to 14.3V and 18minutes. The switch to CV occurs at around 96% SOC, and the 18minutes of CV takes it up to 99% before the charger shuts down. Actually, CV duration should be reduced to 6minutes.

The rebulk voltage is now set to 12.9V and bulk mode charging started at 80% SOC. That sounds fine. When I had it set to 13.3V following the BattleBorn recommendations, bulk mode charging started at 99% SOC. The SOK batteries are a different cell design than the BattleBorn cells so that may account for the difference. 

The voltage shown on the HomeAssistant graphs is being measured at the battery terminals by the Victron shunt. The voltages being used by the Magnum inverter/charger are within the unit itself. There is approximately 12 feet of 2/0 cable between the batteries and the inverter with numerous interconnects. So while charging, the Magnum voltages will be higher due to resistance in the cable and high current. Discharge voltage should be close as the current is low. When the RV is not connected to shore power, the Magnum measured voltages would be lower than actual battery voltage due to high current through the cables. 

Monday - I’m still trying to decide if I’m alright with this behavior. Charger off until ~2:30am with SOC of 74% (that’s good), followed by two CC/CV charges in the morning at SOC of 94% (not optimal), followed by the solar charging in the afternoon, then another CC charge in the evening at SOC of 82%. I think that this may be the best I can do with the Magnum inverter/charger. To get a more accurate battery voltage, I would need to add a Magnum BMK or shunt. Not for $180…

Charging LiFePO4

Friday - This afternoon, I installed the Renogy 40amp DC-DC charger including a 50amp breaker on the input side of the device. Just for future reference, the DIP switch positions I used are in the picture. Off, On, On, On, Off for Lithium batteries, 14.4V. 

This matches the recommendation from BattleBorn for the Renogy 40amp charger. Since there is only about 6” of wire on the output side, I used leftover 8AWG stranded wire. The input side has longer leads so I’ll use the 4AWG cables I ordered from Amazon. 

Saturday - The cables and the new Magnum remote arrived yesterday while I was in the hot tub. The air temperature was 53°F so, needless to say, I was the only one there. 

Around 11am, I switched off the main AC breaker and turned off the inverter. With the DC power still connected, per instructions, I plugged in the new remote panel. It ran through its initialization process and verified that the Magnum ME2012 was firmware v5.94. According to what I’ve read, this is sufficient to provide a CC/CV charging profile.

CC/CV is Constant Current/Constant Voltage. The Magnum is now set up to provide up to 90amps until it reaches the set absorption voltage, which I set to 14.3V. At this point it switches to constant voltage and will maintain this voltage for 0.1hrs. This time is adjustable. You guess on the time to allow the batteries to get fully charged. Since the Magnum is measuring the battery voltage internally, it will read higher than actual battery voltage while charging due to resistive losses in the 2/0 cables. This is about 0.2V at 90amps. After this, the charger goes into “Silent” mode until the battery voltage drops to the “ReBulk” voltage which I have set to 13.0V. According to a table, the is about a 40% SOC which is really low. I tried 13.1V and bulk charging started at an SOC of 99%. All of these parameters are adjustable with the new remote. The short CV time and “Silent” mode are recommended as we have alternate charging options and the allows the batteries to cycle.

I also have the DC-DC charger installed. I just need to run the trigger wire into the next bay and find an appropriate source. Such as the tail light. That way the coach batteries won’t be charging from the engine right after the engine is started. 

BTW, the hydraulic crimper does a fantastic job. This is one of the 4AWG cable for the DC-DC charger before it’s covered with heat shrink. This has been a fun project. 

Battery Project Continues

Tuesday - Yesterday's bulk charge with an absorption voltage of 14.6V proved to be on the high side. Especially with an absorption time of 90 minutes which is the shortest setting available with the current Magnum remote. This triggered the BMS (Battery Management System) on one of the batteries to go into "protect" mode. Essentially disconnecting it from charging. I switched the battery type to gel on the Magnum and turned off charging. After about ten minutes, the battery, the battery came back online. and they both discharged until around noon. I turned the charger back on and it proceeded to finish the 90-minute absorption time before going into float. 

When the Magnum switched to "float" after the 90min absorption, it stopped supplying current to the batteries as the solar controller was still in "bulk" mode as its absorption setting wasn't reached. The Victron solar charge controller does have a LiFePO4 profile and it is set with an absorption voltage of 14.4V and an absorption time of 15 minutes. And a re-bulk voltage differential of 0.4V so it'll start charging again when the voltage drops to 14V.

Wednesday - Todays tasks were removing the batteries and installing the battery disconnect switch and painting the battery box. The switch was installed on the side wall of the bay next to the solar charge controller circuit breaker. The box was also disassembled and glue was added. Steel eyelets were installed for a ratchet strap to anchor the box and batteries. I only painted the sections of the box that I couldn’t get to easily when the box is in the bay. Especially where the wood contacts the steel bottom of the bay. 

Thursday - Participated in the morning test session before going for a walk around the park. I have an Apple appointment later on today as my iPhone 13 Mini doesn't want to power on. I moved the SIM card to my old iPhone X and after a while, it started working on AT&T again. Maybe because the hardware identifier within the phone changed. I believe that the phone is still under warranty as it is less than a year old. 

Update - The iPhone 13 Mini started to work again so I cancelled the appointment. I also finished painting the box and added some aluminum trim to the lid. The ratchet strap is to hold the box and batteries in place. Still a little more work before this project is finished. 

Magnum Issues

Warning, very tech-y post...

Sunday - The Magnum inverter/charger ran on the “Flooded” setting yesterday and it got the batteries up to 14.6V in absorption mode. It then dropped to float and kept the batteries at 13.4V for the next four hours. After four hours, the charger switches to “battery saver” or standby where the current drops to zero. By design, the charger will remain on standby until the voltage drops to below 12.8V at which time another four-hour float mode is initiated. Current will be supplied to get the batteries back up to 13.4V.

The problem with this system is voltage won’t drop to 12.8V until the state of charge (SOC) is ~17%. Clearly, this isn’t going to work. Today, I turned off the main breaker for a few minutes and when I turned the breaker back on, a four-hour float charge cycle was initiated. This got the SOC up to 82% from 60%. 

Monday - Today, the goal was to get the battery voltage down to around 12.7V. At this time, I can turn off the main breaker for five minutes. When AC power is switched back on, the Magnum charger should go into bulk/absorption and charge the batteries up to 14.6V before switching to float. 

This happened at 6:18pm. The voltage was down to 12.68V. I turned off the main breaker for 5min. After it was turned back on, the charger went to bulk charging mode at 100amps, of which 70amps were going into the batteries. The remaining 30amps were the 12V draws within the RV. When the batteries were fully charged, the voltage jumped to the absorption voltage and the current dropped to zero. The charger will sit in the absorption mode for an hour before dropping to the float mode for four hours. After this, the charger will shut down. This was a test to see if I understood how the Magnum inverter/charger works. If dry camping, the generator would end up running for five hours to charge up the battery bank.

I did go out and check temperatures and all was good. No hotspots. The Victron temperature sensor on the negative post registered a max of 107°F at the end of the bulk cycle. The warmest thing was the inverter/charger. 

I think I have found a solution to this problem. The inverter is a model ME2012 with version 5.9 firmware. I ordered a new wired remote panel which should have more options. At least enough to create a custom charge profile compatible with LiFePO₄ batteries. The remote has been ordered. 

Battery Project - Part 2

Thursday - Worked on the battery compartment for most of the afternoon. Two coats of Rustoleum paint and then fitted 1½” of foam around the battery holdown brackets that are welded to the bottom of the bay. A layer of 1” and a layer of ½” foam will be followed by a piece of ½” plywood that the batteries will rest on.

Friday - In the middle of the battery project, I paused to build a house. Dave, one of the work campers here, made all of the gingerbread and it was pretty tasty. Way better than the kits I usually get. 

But back to the battery project. I made an insulated plywood box for the batteries and sized the box to allow one more battery. The cables are 2/0 AWG welding cable. I used pocket screws to assemble the box. This is the first time I’ve used them. 

I’ll use 1” rigid foam to fill in the space for the space reserved for the third battery and possibly remove everything to paint the plywood. I also need to order a main 12V shutoff switch since the relay is not functioning. 

We have an older inverter, a Magnum ME2012 with a ME remote. There is no lithium battery type within settings. The “Flooded” profile has a bulk/absorption voltage of 14.6V which is at the upper end of the recommended voltage. The AGM profile is lower than recommended at 14.3V for bulk/absorption but the float voltage is way too low at 13.1V This means that the Magnum ME2012 will not fully charge the new batteries. The Victron solar controller does have a lithium profile so it'll make up the difference. I have it set to “AGM” for now but may change it to “Flooded” later.

Saturday - This morning after the test session, I hooked up the batteries. After turning on the charging function of the inverter, I monitored the battery voltage on the BMV-712. I removed the Magnum battery temperature sensor as that would cause the bulk/absorption charge voltage to deviate based on temperature and raised the max output from the charger to 100amps. According to the lithium battery sites, we don’t want the temperature feature. 

The project is about 75% done. I still need to install the battery cutoff switch (just ordered yesterday) and the DC-DC charger and 50amp breaker. The DC-DC charger is for charging from the engine on long drive days. 

I’m also planning to paint the box and fasten it down to the bottom of the bay. Even including the box, the new system is over 150lbs lighter than the old flooded golf cart batteries and over twice the capacity. It looks like the Magnum works as advertised. It stopped charging at 14.3V. More on the Magnum later…

Battery Project - Part 1

Monday - Now starts the planning process for the battery installation. Since the battery bay is an uninsulated compartment, I will be building an insulated box for them. 

The bottom of the battery bay is sturdy metal and Home Depot has 1” rigid insulation in 2’x2’ pieces. I think that’ll work for the bottom of the box. A piece of 1/2” plywood will distribute the load onto the foam. The box itself will simply be 1/2” plywood with 1/2” insulation inside with the same construction for the top. 

I’ve identified most of the cables shown in the first picture and I want to relocate a couple of them that will be hard to access once the box is in place. The large, cylindrical relay on the right will be removed and replaced with a DC-DC charger. This relay is energized when the engine is running to allow the engine alternator to charge the coach batteries. The alternator is rated at 160amps and the DC-DC charger will limit the current to 40amps. The internal resistance of LiFePO4 batteries is very low and it will max out the alternator (burning it out) and possibly exceed the max charge rate of the batteries (70 amps each). The other purpose of the relay is to “jump” the chassis batteries in case they are dead. 

Wednesday - The batteries arrived already, three days before they promised. I checked the voltage on them and they are both partially charged. The batteries also have Bluetooth built into the BMS (Battery Management System) so I can see the individual cell voltages and the internal temperature. This is an unexpected feature. The next screenshot shows how the battery shows up on the phone screen.

At the top of the screen is the SOC (State of Charge) but it won't reflect reality until after a couple of complete charges. There is a switch for heating but I didn’t get that option. At the bottom are the individual cell voltages. Pretty cool! 

The first task was removing the old batteries and wiring them back up to the RV so we still have 12V functionality. Another RVer here in the park loaned me a set of jumper cables so I could temporarily power the RV off of the old batteries. The battery bay has a lot of rust on the bottom where the flooded lead acid batteries were sitting so I'm going to paint the floor before starting to build the battery box. The rust is just on the surface and the Rustoleum paint that I already have says to just remove the loose rust and clean with soap and water. This afternoon, picked up a drill mounted wire brush and used that do get rid of as much of the surface rust as I can. Tomorrow, paint. 

Another Potential Issue

Friday - An observation that I made yesterday evening after getting an alert from the Victron battery monitor yesterday morning. The alert was for battery voltage dropping below 12VDC on the morning of Nov 24. 

This chart indicates that 12VDC is around 50% charge which is about as low as you want to go when using lead acid batteries. At this point, we had only used about 120AH of the 420AH of capacity. This is the capacity when the batteries were still new. 

I adjusted the battery capacity on the battery monitor to only 210AH, turned off the charging function on the inverter, and we’ll keep an eye on it. The batteries are still working and we do have a generator so it’s not anything critical. Especially since we don’t dry camp a lot.

In the middle of the afternoon, I’m trying to figure out what is drawing 228watts. The refrigerator plus fans are drawing about 80-100watts. The inverter is off and the basement fridge is on shore power. Maybe the two fans are drawing about 80 watts between the pair. All more than I thought. 

Saturday - Early this morning, I checked the SOC (state of charge) and the battery voltage and adjusted the battery bank capacity to match what I was seeing. The battery voltage was still around 12.25VDC so I raised the capacity to 265AH. This raised the SOC to 62% which matches the chart shown above.

I think that our batteries were discharged to almost zero when it was in the shop. Initially, I had the batteries disconnected but the shop needed them on to operate the slides and steps. They were left on for weeks while waiting for parts and when I picked the RV up, the coach batteries were almost completely dead. We may be replacing batteries next month as we won't be able to make it through the night if we need to use the furnace.

A morning project was making this little steering wheel table from wood left over from other projects. The steering wheel is tilted up right now. Some people like driving it the RV with the wheel almost horizontal as it gives them more leverage. I prefer it down at a more familiar angle. 

Sunday - It’s looking like we will be ordering some batteries in the near future. Even without using the propane furnace, our batteries are already dipping down to 60%. 

I’m pretty convinced to get two of the 206AH, 12V SOK batteries without the internal heaters and BT. They are slightly larger and a couple of inches taller than the each of the four existing 6V golf cart batteries. They have a maximum continuous discharge rate of 100amps each so if we upgrade to a 3K inverter, we will need to add a 3rd battery. I am planning to install them in a homemade insulated box in the battery compartment. I can make my own silicone heat pad temperature control with a small WiFi enabled microprocessor. 

I need to also order a DC-DC charger for engine charging. The existing cables are adequate but I’ll need some jumper cables to allow me to remove the existing batteries from the compartment and still have the coach powered up. 

The old Magnum inverter/charger doesn’t have a LiFePO4 charge profile but the solar charge controller does. The Magnum can charge the batteries to ~80% SOC and the solar can top them off if needed. I had originally thought that I needed to change out the inverter/charger first but this should work fine.