Search results

  1. Maast

    Whats the difference between the 'N' vs 'K' 280AH cells from Amy?

    Havent been on the forum much lately, summer projects have taken precedence (~1850 yards of fill dirt to level out back yard, sprinkler system and fence) but I'm starting the research phase of adding on to my monster sized BYD bank and I noticed Amy has two types of cells and am wondering what...
  2. Maast

    JK BMS balancer 'gotcha' I just encountered

    I thought I'd just pass along a 'gotcha' I encountered on my JK BMS (also known as a Heltec) bluetooth active balancer that had me in a panic for a couple of days. Hopefully if somebody in the future searches the symptoms they'll find this post. I powered it off by unplugging the molex block...
  3. Maast

    Any downsides to transplanting my 1300000uF capacitor from old SLA bank to new LFP bank?

    I can't think of any downsides to transplanting the 130000uF electrolytic capacitor to the new LFP bank other than having to be really careful with precharging. It was on the old bank to help out the inverter with sudden high loads and a bad inverter induced DC ripple under heavy load. The new...
  4. Maast

    Anybody actually running their Chargery using the external power port connected to the pack via a diode?

    I dont remember reading somebody actually doing it, just a couple of theoretical discussions about it and a search didnt turn up anything. I'm thinking I'm going to run my 16T through a couple of diodes in series (40v 20A diodes I've got laying around) and an small toriod inductor to connect to...
  5. Maast

    My 64kwh BYD battery bank

    Finally got my 18 module BYD bank complete. It's the most polished turd you'll ever see. About 6 months of stripping, cycling, testing and correcting. 2160lbs. I ended up adding 65ish 15ah cells to correct the undercapacity cells in the modules. Each cell is paralleled with 6 gauge wire and...
  6. Maast

    What separate unit 250V+ Charge Controllers are available?

    The other thread just got me thinking about what other single unit 250V+ voltage charge controllers are available. The only ones I know of are the Victron 250s, the Midnite 250s and the Outback 300s. All of which are really expensive. I've got three of the 'crippled' Midnite 250s that I got...
  7. Maast

    Are we getting 'trolled'?

    It seems to me there is a sudden flood of new users that are asking super-vague questions without details that seem calculated to use up as much research time for a answer-er as possible. And getting them to clarify what they're asking about is like pulling teeth. This is beyond the usual...
  8. Maast

    I bet solar w/ battery is about to get wildly popular in Texas. Minimum system size?

    What do you think the minimum sized system would be to keep the lights on, refrigerator running, and the furnace going while doing extreme conservation in the average Texan house? I did a quick set of calculations and assuming a gas furnace it came out surprisingly small inverter at only 3000W...
  9. Maast

    EMP-proofing my system with tvs diodes design idea

    I've been back-of-the-envelope designing supplemental EMP and transients protection for my system using tvs diodes in conjunction with the Midnight lightning arresters (I can build them cheaper than just buying them, but they're inexpensive and the time savings is worth it). I recently saw...
  10. Maast

    Best electrical enclosures ever!

    Found the perfect series of metal electrical enclosures to hold all the battery paraphernalia: DC breakers, shunts, contactors, etc, etc, etc. They go from little 8 inch by 8 inch jobbies though every size and depth you can think of up to huge ones like 34x32x12. I just picked up a...
  11. Maast

    Source for non-metallic enclosure for BMS, shunts, relays & DC bus bars?

    Looking for sources for good value plastic/FRP boxes with a door to hold all the battery paraphernalia. I've seen the Buds enclosures on Amazon but he wants a hundred bucks for a plastic box with a door on it and that just seems way overpriced to me. I'm thinking something like 20"x14" or so...
  12. Maast

    Chargery and 48v coil relays?

    After a good bit of thrashing around, I'm now thinking its a very good idea to use 48v coil contactors/relays for 200A and more. The reason being is that you have a 48v source ready to hand and you wouldnt need an additional 12v power source thats burning additional juice to run. The same...
  13. Maast

    Chargery datalogging, whats the current easiest way to extract info and graph a discharge curve

    Currently my datalogging consists of a super-cheap webcam pointed at the screen..... I need something better so I can figure out what my true 80 and 20% amp-hour levels are and convert those to voltages for the charge controllers, inverter, and BMS. I'm a IT guy and a electronics tech but I'm...
  14. Maast

    FYI Gigavac GV series relays only use 2 watts to hold open, and only cost $95 for a 400A

    Probably not of much interest to anybody, but I was poking around their online store looking to pick up another couple of contactors because I was reading the specs on the ones I have and their max coil voltage was 54V. Doh! There goes another couple hundred bucks. At any rate it turns out...
  15. Maast

    What is this Bulk, Absorption, Float, Constant Current, Constant Voltage stuff anyway? An explanation.

    I wrote this in another thread and I thought it'd be useful in it's own thread instead buried 4 pages down. You've might have read me talk about using off-the-shelf CC power supplies to charge cells. The same logic applies to every charger. Lets step through each phase of a charge cycle and...
  16. Maast

    Interesting what's considered a 'Tier 1' chinese inverter, wonder if Amy would be our purchase agent.

    From this page https://suntiago.com/essential-information/brands-ranking/#inverters I've been considering requesting if @Amy Wan (Luyuan) would be interested in acting as a purchase agent for members of the forum for top-quality inverters manufactured in China. Trust is a precious commodity...
  17. Maast

    Anybody measure the standby idle loss on their Phocos 5kw inverters?

    I'm considering one for a smallish off-grid project and since idle loss is a great first-pass indicator of the quality of the unit I'd like to know. They claim 40W but I'd like to know what it really is. MPPs idle loss claims are far less than their actual 74W idle usage.
  18. Maast

    Anybody ever parallel 2 or more of the the Heltec 5A active balancers?

    I think I'm going to need a LOT more balancing amperage: When I'm done each of the cell groups of my 48v BYD bank is going to have 1125AH per cell group. I've got a string of QNBBMs that can do 5-6A but the highest I've seen in actual use is 1.4A with a .25v differential. Even with all the...
  19. Maast

    Built a DIY 20A/cell 8 cell charger for the BYD modules.

    Made a 20A/cell 8-cell charger so I can charge all the cells up to the same voltage. I was having a hell of a time getting a balanced charge for these used BYD modules so I can test them. Built my own because I couldnt find a 8 cell charger that would charge individual cells separately that...
  20. Maast

    15AH LiitoKala 33140 LFP review and test results

    Received 36 cells and 5 cells were either bad or marginal: 3 were completely bad with .021V 1.8V and 2.1V, the marginals had 2.77 and 2.8V - since all the others were 3.0-3.11v (almost all 3.05-3.08V with a few outliers) the marginals had obviously self-discharged and are not something I want...
  21. Maast

    Just bought a stack of these Liitokala 15AH, guess I'll see how good they are

    Bought a stack of these on Aliexpress to even up the mismatched capacity of my BYD packs. According to online reviews their smaller ones are testing out close to capacity so I thought I'd take a gamble - that and how inexpensive they were seem worth it. When you buy 8 it works out to something...
  22. Maast

    Anybody know of a US source of 15AH LFP batteries?

    Need about 12 to finish off the BYD bank and all the headways have seemed to dried up. I can find them on Aliexpress but I don't want to wait until Feb for delivery. Batteryspace has them but they want $40 a pop which is a little spendy. Not necessarily looking for cylindrical cells, just the...
  23. Maast

    Made a Franken-BYD!

    Cut out a bad cell 1 and spliced in a good one from a doner pack. Used 2" ratchet straps to recompress the pack and I tied them down with commercial net cord (technically called no stretch hard lay gangen twine) using what I've always called a double pulley truckers knot. You can get things...
  24. Maast

    Where did all the Headways go?!

    I need another 12 or so to finish up my 18 pack BYD bank - I'm using them to add capacity to the weak cells before I add the pack to the rack and there's always at least one per pack. Went to order them from Battery Clearing House and even their cosmetically ugly ones are sold out. Started...
  25. Maast

    Thermochromic color changing stickers to monitor heat

    Had an idea to monitor battery interconnects and components - use heat sensitive color changing stickers or tape to see if they're hot so I can tell at a glance if something is not right or going bad. From what I've found there are two types, a permanent color change and a temporary change that...
  26. Maast

    At what battery voltage do you set your inverter to start 'selling' power back to the grid?

    I want to maintain my battery bank at around 80% SOC as a reserve to provide enough juice to keep the house going if the grid goes down so I'm thinking of setting mine to about 52.8V (exact voltage @80% to be determined later). I'm actually not sure if I'm going to grid-tie at all as the...
  27. Maast

    ISO inexpensive 48V inverter for test bench

    Anybody got a cheapie (without being so cheap its crap) inverter they're looking to get rid of? I need something for my test bench area for a test load, about 4000-6000 watts or so. I've been using a couple of APC SURTA 2200s that I modified that're paralleled together but would like something...
  28. Maast

    BYD Modules Redux! Comparison test of active balancing VS adding capacity to weak cells (pics)

    Summary: I ran a series of 6 full charge/discharge tests with/without active balancing and/or with/without adding capacity. The BYD module I tested had 1 badly undercapacity and one moderately undercapacity cell and has a unmodified 3.2kwh capacity. At a 1700W discharge rate with only active...
  29. Maast

    Need help adjust bulk voltage on 16 year old non-VE.Bus Victron Multiplus 24/3000

    Looks like the inverter I got for $400 was a lot older than I thought. According to Victron support the serial number says it was made in 2006. Be interesting to see how it does when I put some real loads on it. At any rate, after a lot of manual studying and head scratching I figured out how...
  30. Maast

    Bought a 9 year old Victron Phoenix Multiplus 24/3000 for $400. Good deal? Or waste of money

    Craigslist find. Initial test is that it charges and inverts but I havent put any real load on it - just a 100W lamp and about 5 amps of charging current to old tiny little AGMs out of a APC UPS. So what is the longevity of the Victrons? Especially this first generation of the Multiplus, for...
  31. Maast

    Whats the latest in DC-DC charging on a vehicle that doesnt break the bank?

    Whats the latest best value DC-DC charger from the starter battery to the house bank? The latest I remember seeing was a 50A from Renology but that sucker is 300 bucks, is there anything out there thats a better value that doesnt require connection to the ignition switch? Havent been posting...
  32. Maast

    Cheapest 24V 1500w inverter/charger thats worth a d@mn

    Just smoked my modified APC Smart UPS SUA1000, we had the power go out and I didnt have the cooling fan enabled because I'd turned it off and forgot about it. I need a inexpensive good value inverter/charger to act as a UPS for a while until get the Radian based whole house UPS going. I could...
  33. Maast

    BYD modules: adding 18650/headway LFP cells to correct for weak module cells

    Just saw a post on the DIY battery facebook group about adding cells in parallel with individual weak cells in the BYD modules to correct for them not being up to par. I'm thinking its a pretty good idea. There'd be a good bit of trial-and-error with adding a cell, cycling it to see the...
  34. Maast

    I just discovered cheap automotive 18ga 9 conductor audio "Speed Wire" just the thing for BYD modules

    I've been looking all over for wire that doesnt break the bank to hook up the 8 individual cells in the modules to aggregate/parallel all the cells into 16 cell groups w/ 12 cells per group to attach the Chargery cell monitor and 1S active balancer daisy chain. If I were to do it with...
  35. Maast

    The BYDs from Batteryclearinghouse have arrived.

    Took a bit but they're here. Bought it on the 12th and they arrived on the 30th. UPS tracking said the pallet actually arrived in the local area the 24th. Not too terribly bad coming from the far side of the country. Pretty good deal for $300 a pop and they gave me a 'bakers dozen' for the...
Top