[{"data":1,"prerenderedAt":412},["ShallowReactive",2],{"guide-en-jk-bms-balance-settings":3,"guides-en":355},{"id":4,"title":5,"body":6,"date":333,"description":334,"extension":335,"keywords":336,"meta":344,"navigation":345,"path":346,"related":347,"seo":351,"stem":352,"updated":353,"__hash__":354},"guides_en\u002Fguides\u002Fjk-bms-balance-settings.md","JK BMS Balance Settings: Start Voltage, Trigger, Current",{"type":7,"value":8,"toc":313},"minimark",[9,13,18,21,39,50,54,59,62,65,68,71,74,77,80,84,87,90,103,107,110,197,204,208,211,238,241,259,263,278,282,285,289,292,296,303],[10,11,12],"p",{},"The JK BMS balance settings are four values: the Balancer switch, Start balance voltage, Balance trigger voltage and Max balance current. The active balancer works only when the switch is on, at least one cell is above the start voltage, and the gap between the highest and lowest cell is larger than the trigger. For LFP, a start voltage around 3.40 V and a trigger of 0.005 to 0.01 V is a good starting point.",[14,15,17],"h2",{"id":16},"how-the-jk-active-balancer-decides-to-act","How the JK active balancer decides to act",[10,19,20],{},"The JK balancer is active, not passive. It moves energy from the highest cell to the lowest instead of burning it as heat. Two conditions must both be true before it moves anything:",[22,23,24,33],"ul",{},[25,26,27,28,32],"li",{},"A cell is above ",[29,30,31],"strong",{},"Start balance voltage",".",[25,34,35,36,32],{},"The difference between the highest and lowest cell is larger than ",[29,37,38],{},"Balance trigger voltage",[10,40,41,42,45,46,49],{},"It keeps working until the difference drops below the trigger. ",[29,43,44],{},"Max balance current"," is the ceiling for how much current it moves between cells. The ",[29,47,48],{},"Balancer"," switch turns the whole function on or off.",[14,51,53],{"id":52},"the-four-parameters","The four parameters",[55,56,58],"h3",{"id":57},"balancer-switch","Balancer (switch)",[10,60,61],{},"This enables the active balancer. Keep it on. The editor help says to combine it with a sensible start voltage so it does not work on the flat part of the curve.",[55,63,31],{"id":64},"start-balance-voltage",[10,66,67],{},"Balancing runs only above this cell voltage. Keep it below Cell RCV, otherwise the cells never reach it. The editor also warns when Start balance voltage is not below Cell RCV.",[55,69,38],{"id":70},"balance-trigger-voltage",[10,72,73],{},"This is the cell difference that starts balancing, and it also stops balancing when the difference falls below it. JK recommends 0.005 V for cells over 50 Ah and 0.01 V for smaller cells. Below about 5 mV the balancer mostly reacts to measurement noise and wire resistance.",[55,75,44],{"id":76},"max-balance-current",[10,78,79],{},"The highest current the balancer moves between cells. Match it to the hardware: 2 A on PB2A boards, 1 A on PB1A boards.",[14,81,83],{"id":82},"why-lfp-should-balance-only-near-the-top","Why LFP should balance only near the top",[10,85,86],{},"An LFP cell has a long, flat voltage curve. Between roughly 10% and 90% state of charge the voltage barely changes, so a 20 mV gap there says almost nothing about the real charge difference. Real differences show up at the top knee, where voltage rises fast.",[10,88,89],{},"If Start balance voltage is too low, say below about 3.35 V, the balancer works on the plateau. It wastes energy moving charge based on noise. Worse, it can move charge the wrong way and push the pack further out of balance. Starting at 3.40 V keeps balancing in the part of the curve where voltage tells the truth.",[10,91,92,93,98,99,32],{},"This is also why RCV time matters. If charging ends before the cells spend time above the start voltage, the balancer has no window to work. See ",[94,95,97],"a",{"href":96},"\u002Fguides\u002Fjk-bms-lifepo4-settings","JK BMS settings for LiFePO4"," for the full voltage set. Unbalanced cells also make the SOC reset early, which is covered in ",[94,100,102],{"href":101},"\u002Fguides\u002Fjk-bms-soc-calibration","JK BMS SOC calibration",[14,104,106],{"id":105},"jk-bms-balance-settings-by-chemistry","JK BMS balance settings by chemistry",[10,108,109],{},"Ranges come from the recommendations in the editor. The NMC and LTO start voltages are less well sourced than the LFP ones, so treat them as a starting point and check your cell datasheet.",[111,112,113,135],"table",{},[114,115,116],"thead",{},[117,118,119,123,126,129,132],"tr",{},[120,121,122],"th",{},"Parameter",[120,124,125],{},"LFP range",[120,127,128],{},"NMC range",[120,130,131],{},"LTO range",[120,133,134],{},"Medium preset (LFP \u002F NMC \u002F LTO)",[136,137,138,152,168,183],"tbody",{},[117,139,140,143,146,148,150],{},[141,142,48],"td",{},[141,144,145],{},"on",[141,147,145],{},[141,149,145],{},[141,151,145],{},[117,153,154,156,159,162,165],{},[141,155,31],{},[141,157,158],{},"3.40 to 3.45 V",[141,160,161],{},"3.90 to 4.00 V",[141,163,164],{},"2.40 to 2.50 V",[141,166,167],{},"3.40 \u002F 3.90 \u002F 2.40 V",[117,169,170,172,175,178,180],{},[141,171,38],{},[141,173,174],{},"0.005 to 0.01 V",[141,176,177],{},"0.005 to 0.015 V",[141,179,177],{},[141,181,182],{},"0.01 \u002F 0.01 \u002F 0.01 V",[117,184,185,187,190,192,194],{},[141,186,44],{},[141,188,189],{},"1 to 2 A",[141,191,189],{},[141,193,189],{},[141,195,196],{},"not set by presets",[10,198,199,200,32],{},"The gentle LFP preset tightens the trigger to 0.005 V. The presets never change Max balance current, so set it to match your board. You can see all levels on the ",[94,201,203],{"href":202},"\u002Fpresets","presets page",[14,205,207],{"id":206},"jk-bms-balance-not-turning-on","JK BMS balance not turning on",[10,209,210],{},"Check these in order:",[212,213,214,220,226,232],"ol",{},[25,215,216,219],{},[29,217,218],{},"Balancer switch is off."," Open the settings and confirm it is enabled.",[25,221,222,225],{},[29,223,224],{},"All cells are below Start balance voltage."," A pack resting at 3.30 V will not balance with a 3.40 V start. Charge higher or lower the start voltage within the range above.",[25,227,228,231],{},[29,229,230],{},"The difference is below Balance trigger voltage."," If the cells differ by 4 mV and the trigger is 5 mV, there is nothing to do. That is normal.",[25,233,234,237],{},[29,235,236],{},"Start voltage is above what the pack reaches."," If Cell RCV or the charger stops below the start voltage, the balancer never starts.",[10,239,240],{},"There is no separate \"balance only while charging\" flag among the fields this editor reads, so the four parameters above are the full balance set.",[10,242,243,244,248,249,253,254,258],{},"To tell imbalance from a charger setpoint problem, load the Detail Log on the ",[94,245,247],{"href":246},"\u002Flogs","log analysis page",". Read ",[94,250,252],{"href":251},"\u002Fguides\u002Fjk-bms-weak-cell-log","finding a weak cell in the log"," to see how a lagging cell looks in the data, and ",[94,255,257],{"href":256},"\u002Fguides\u002Fjk-bms-cell-overcharge-protection-tripping","why cell overcharge protection keeps tripping"," for trips caused by a charger set above cells × Cell OVP.",[14,260,262],{"id":261},"common-mistakes","Common mistakes",[22,264,265,268,271],{},[25,266,267],{},"Setting the start voltage on the LFP plateau to \"balance all the time\".",[25,269,270],{},"Setting the trigger very low and chasing noise.",[25,272,273,274,32],{},"Trusting cell differences when wire resistance is off. A bad balance lead gives wrong readings, and the BMS then balances a gap that is not real. Healthy leads read about 0.045 to 0.055 Ω. See ",[94,275,277],{"href":276},"\u002Fguides\u002Fjk-bms-wire-resistance","JK BMS wire resistance",[55,279,281],{"id":280},"what-is-a-good-balance-trigger-voltage-for-jk-bms","What is a good balance trigger voltage for JK BMS?",[10,283,284],{},"For LFP, 0.005 to 0.01 V. Use 0.005 V for cells over 50 Ah and 0.01 V for smaller ones.",[55,286,288],{"id":287},"does-a-higher-balance-current-balance-faster","Does a higher balance current balance faster?",[10,290,291],{},"Yes, up to the hardware limit. Do not set more than the board supports: 2 A on PB2A, 1 A on PB1A.",[55,293,295],{"id":294},"should-the-balancer-always-be-on","Should the balancer always be on?",[10,297,298,299,32],{},"For most packs, yes. Keep the switch on and control when it works with the start voltage. For every other field, see ",[94,300,302],{"href":301},"\u002Fguides\u002Fjk-bms-parameters-explained","JK BMS parameters explained",[10,304,305,309,310,32],{},[94,306,308],{"href":307},"\u002F","Connect your BMS or open your .jkcfg"," in the editor to check the balance values, or start from a ready ",[94,311,312],{"href":202},"preset",{"title":314,"searchDepth":315,"depth":315,"links":316},"",3,[317,319,325,326,327,328],{"id":16,"depth":318,"text":17},2,{"id":52,"depth":318,"text":53,"children":320},[321,322,323,324],{"id":57,"depth":315,"text":58},{"id":64,"depth":315,"text":31},{"id":70,"depth":315,"text":38},{"id":76,"depth":315,"text":44},{"id":82,"depth":318,"text":83},{"id":105,"depth":318,"text":106},{"id":206,"depth":318,"text":207},{"id":261,"depth":318,"text":262,"children":329},[330,331,332],{"id":280,"depth":315,"text":281},{"id":287,"depth":315,"text":288},{"id":294,"depth":315,"text":295},"2026-10-02","JK BMS balance settings explained: start balance voltage, balance trigger voltage, max balance current and the Balancer switch, for LFP, NMC and LTO.","md",[337,338,339,340,341,342,343],"jk bms balance settings","jk bms balance trigger voltage","jk bms start balance voltage","jk bms balance current","jk bms balance not turning on","jk bms active balancer settings","jk bms balance switch",{},true,"\u002Fguides\u002Fjk-bms-balance-settings",[348,349,350],"jk-bms-lifepo4-settings","jk-bms-weak-cell-log","jk-bms-wire-resistance",{"title":5,"description":334},"guides\u002Fjk-bms-balance-settings","2026-10-04","SUm9iGl-elme824jAoGa8YRNSO2-GB0ps8OaeqiM9LE",[356,361,362,365,369,373,376,380,384,388,391,395,399,403,406,409],{"path":357,"title":358,"description":359,"date":353,"updated":360},"\u002Fguides\u002Fjk-bms-bluetooth-browser","Change JK BMS Settings over Bluetooth in Your Browser","Connect to a JK BMS from Chrome or Edge, read every setting, apply a preset and write it back in a safe order with read-back checks. No JK app needed.",null,{"path":346,"title":5,"description":334,"date":333,"updated":353},{"path":256,"title":363,"description":364,"date":333,"updated":360},"JK BMS Cell Over Charge Protection Keeps Tripping: Causes and Fix","JK BMS cell over charge protection tripping and releasing every minute? See why a charger set too high causes it, how to tell it from a weak cell, and how to fix it.",{"path":366,"title":367,"description":368,"date":333,"updated":353},"\u002Fguides\u002Fjk-bms-detail-log","How to export and read the JK-BMS Detail Log","What the JK-BMS Detail Log contains, how to export it from the app, how to read its events and what the log analysis page tells you about trips and faults.",{"path":370,"title":371,"description":372,"date":333,"updated":353},"\u002Fguides\u002Fjk-bms-export-import-settings","Export and Import JK BMS Settings: The .jkcfg File Guide","How to export and import JK BMS settings with the app, what the .jkcfg file contains, why hand edits break it, and how to edit it safely in your browser.",{"path":96,"title":374,"description":375,"date":333,"updated":353},"JK BMS Settings for LiFePO4: 8S and 16S, 280Ah and 314Ah","JK BMS settings for LiFePO4 packs: per-cell voltage, balance, current and temperature values for 8S and 16S with 280Ah and 314Ah cells, in three wear levels.",{"path":377,"title":378,"description":379,"date":333,"updated":360},"\u002Fguides\u002Fjk-bms-log-messages-explained","JK BMS Log Messages Explained: Boot, Time calibration, Protections","What each JK BMS log message means: Boot, Time calibration, APP open charge, protection trips and releases, Discharge On Failed and Unknown Log Code [0].",{"path":381,"title":382,"description":383,"date":333,"updated":353},"\u002Fguides\u002Fjk-bms-nmc-lto-settings","JK BMS Settings for NMC and LTO: Safe Per-Cell Values","JK BMS settings for NMC and LTO packs: per-cell OVP, UVP, balance, temperature and C-rate values in three wear levels, plus how the editor detects chemistry.",{"path":385,"title":386,"description":387,"date":333,"updated":353},"\u002Fguides\u002Fjk-bms-ocp-scp-settings","JK BMS Overcurrent Protection Settings: OCP and SCP Guide","JK BMS overcurrent protection settings explained: charge and discharge OCP limits, delays, recovery times and SCP, with ranges and sizing for inverters.",{"path":301,"title":389,"description":390,"date":333,"updated":353},"JK BMS Parameters Explained: Every Setting by Group","JK BMS parameters explained in one glossary: cell OVP, OVPR, UVP, UVPR, balance, SOC, RCV and RFV, current and temperature limits, with typical LFP ranges.",{"path":392,"title":393,"description":394,"date":333,"updated":353},"\u002Fguides\u002Fjk-bms-password","JK BMS Password: Default Codes, Change and Reset Guide","Your JK BMS password is really two codes: Bluetooth and settings. See factory defaults, how to change them, what to try if one fails, and what to do if lost.",{"path":396,"title":397,"description":398,"date":333,"updated":353},"\u002Fguides\u002Fjk-bms-reboots-power-events","JK BMS Reboots and Charge MOS Off: Reading Power Events in the Log","JK BMS reboots or the charge MOS switched off by itself? Learn to read Boot rows and MOS state in the Detail Log and tell expected restarts from real faults.",{"path":400,"title":401,"description":402,"date":333,"updated":353},"\u002Fguides\u002Fjk-bms-sending-failure","JK BMS Sending failure: Causes and Step-by-Step Fix","JK BMS Sending failure on import? See why the firmware rejects settings (voltage chains, write order, SCP delay) and how to fix it step by step.",{"path":101,"title":404,"description":405,"date":333,"updated":353},"JK BMS SOC Calibration: Fix SOC Drift, Jumps and Reset","JK BMS SOC calibration explained: why SOC drifts or jumps, what the SOC-100% voltage and SOC-0% voltage do, and how to set them and recalibrate the pack.",{"path":251,"title":407,"description":408,"date":333,"updated":360},"Find a Weak Cell with the JK BMS Log: Trips, Spread and Balance","Find a weak cell in the JK BMS Detail Log: which cell trips first, how wide the spread is at the trip, and whether it is balance drift or a bad cell.",{"path":276,"title":410,"description":411,"date":333,"updated":353},"JK BMS Wire Resistance: Fix Abnormal Balance Wire Alarm","JK BMS wire resistance explained: what the abnormal resistance of the balance wire warning means, normal values, common causes and how to fix a bad lead.",1791151314585]