jtt electronics t-series bms data sheet · t-series bms data sheet commercial confidential...

Web: www.jttelectronics.com

Phone: 604.324.7530

Fax: 604.327.6686

every last ion.

Document Number: 000193-C

T-Series BMS

Data Sheet

15 or 16 cell battery pack monitoring and control, passive cell

balancing, configurable isolated RS-485, diagnostic isolated R232,

ultra-low power consumption, on-board current sensor and relay

protection

T-SERIES BMS DATA SHEET

Commercial Confidential DN000193-C

i

Copyright

Copyright © 2013 JTT Electronics Ltd. (“JTT”) All rights reserved.

Disclaimer This data sheet is provided in association with, and is subject to, the terms and conditions contained in the “Standard Terms and Conditions of Sale for JTT Electronics Ltd.” for JTT Products. This includes the “Limited Warranty and Remedy”, “Limitations of Liability”, and “Disclaimer and Release” sections of those Standard Terms and Conditions.

The information contained throughout this manual is thought to be up to date at the time of publication. JTT will endeavour to maintain this manual to reflect the most current information about the purchased products, but has no obligation to do so. JTT reserves the right to change the contents of this manual at any time without notice and assumes no liability for its accuracy.

In the preparation of this data sheet, JTT has incorporated and/or compiled service information and maintenance procedures sourced from manufacturers and vendors of parts and components used in the manufacturing of this product. JTT has relied on those manufacturers and vendors for that information and has not verified it. The content of that third party information is not within JTT’s control, and JTT cannot and will not take responsibility for that information. JTT shall not be liable for errors, omissions, missing data or any other matter, in respect of that information.

It is not the intention of this data sheet to instruct personnel in using common sense, basic skills, and rules of, installation, service or repair. The customer is solely responsible for installing the products and for undertaking the installation in a safe environment, using appropriate equipment, by experienced personnel.

Confidentiality

The information contained in this document is the intellectual property of JTT Electronics Ltd. and is Commercially Confidential, subject to the confidentiality provisions of the “Standard Terms and Conditions of Sale for JTT Electronics Ltd.” No part of this document may be reproduced or transmitted in any form or by any means, electronic or mechanical, for any purpose, without the express written permission of JTT Electronics Ltd.



ii

Table of Contents

1. FEATURES ................................................................................................................................................... 1

2. DESCRIPTION ............................................................................................................................................ 2

3. APPLICATIONS .......................................................................................................................................... 2

4. COMPLIANCE ............................................................................................................................................. 2

5. OPERATIONS ............................................................................................................................................. 3

6. BLOCK DIAGRAM ..................................................................................................................................... 5

7. TYPICAL APPLICATION ......................................................................................................................... 6

8. ELECTRICAL CHARACTERISTICS ...................................................................................................... 7

9. APPLICATION INFORMATION ............................................................................................................ 9

10. TYPICAL WIRING .................................................................................................................................. 11

11. CONNECTORS AND PIN OUT ............................................................................................................ 13

12. SIZE AND MOUNTING ......................................................................................................................... 17

13. BMS LINK SOFTWARE ........................................................................................................................ 19



1

1. FEATURES

Measures 15 or 16 cell voltages in series

Measures 4 cell temperatures

thermal management peripheral control

Capable of 50 A continuous charge or discharge

current

Usable in parallel with other T-Series BMS

battery packs

50 mA passive cell balancing

State of Charge, State of Health, capacity, and

DC resistance calculations

Isolated RS-485 and isolated RS-232

DIP switch for RS-485 address selection

Monitors internal PCB temperature

Detects loose cell-to-cell connections

Protects against: short circuit, reverse voltage,

overvoltage, undervoltage, overcurrent, over-

temperature

Onboard high-power solid state relay with

protection

ASCT (Adaptive Smart Connect Technology):

allows the relay to close with resistive loads,

capacitive loads, and combinations of both

IAR (Intelligent Automatic Reconnect):

automatically reconnects the battery post-fault

when safe operating conditions are met

BMS power input from 25-64 V

Onboard current sensor monitoring

Extreme low-power mode

Fault management and diagnostics

User configurable alarm thresholds

LED indicators: State of Charge, run, and alarm On/off push button

Data logging

Alarm logging of up to 1000 alarm events with

64 data points each

PCBA manufactured in ISO Class 5 cleanroom



2

2. DESCRIPTION

The JTT T-Series Battery Management System (BMS) controllers are compact and economical low-voltage battery control systems. This all-in-one BMS controller was designed for the telecom industry and can monitor battery packs of 15 or 16 cells. No additional current sensor or external relays are needed. The T-Series controller is compatible with all lithium cell chemistries and all cell form factors. Each T-Series controller communicates battery fault conditions, cell status information, and battery data via isolated RS-485 and isolated RS-232. This information can be sent to a display, monitoring system, or an intelligent power supply depending on the application. RS-485 can be configured for MODBUS or any custom communication protocols. RS-232 is used to communicate with JTT Electronics software for monitoring, data logging, and troubleshooting. In extreme operating conditions, the T-Series controller is designed to disconnect the battery by opening solid state relays. This helps ensure safe operation and protect the battery pack against

short circuits, reverse voltage, over-charge, over-discharge, overcurrent, and over-temperature conditions. The IAR system (Intelligent Automatic Reconnect) monitors active fault conditions, and upon fault removal, safely reconnects the battery pack to resume normal operation. The BMS software system runs over 25 diagnostic checks at 10 times per second, monitoring individual cells and the entire battery pack. Most of these diagnostics help ensure safe operation of the battery pack, while others monitor battery performance and lifetime. The T-Series BMS passively balances the charge between all cells in the battery pack. Energy is discharged from the cells with the highest charge in the pack, which maximizes the runtime of the battery pack and extends its life. In addition, the T-series controllers are equipped with 6 LEDs: 2 LEDs show running status, and 4 show state of charge.

3. APPLICATIONS

Backup and standby battery systems

Telecom, cell sites, FTTx backup power

Load leveling battery systems

4. COMPLIANCE

IEC 6100-4-2: 2001 (GB / T 17626.2-2006)

IEC6100-4-5: 2005 (GB / T 17626.5-2008)

IEC 60068-2-1: 1990 (GB / T 2423.1-2001)

EN55022: 2006 (YD / T 983)

YD / T 1363.3-2005

YD / T 2344-2011



3

5. OPERATIONS

Cell voltages are sampled every 50 ms to

ensure fast-response protection for even the briefest overvoltage and undervoltage events. Cell monitoring has 1.5 mV resolution and less than 0.5% error.

Temperature monitoring of 4 temperature

sensors ensure that battery pack safety is always maintained and cell lifetime is maximized by avoiding high temperature events that deteriorate cell performance.

State of Charge (SOC) is dynamically

calculated with advanced self-correcting model based algorithms that maintain less than 5% SOC error with slight variance depending on cell chemistry. SOC algorithms dynamically adapt to aging cell characteristics that occur naturally over time.

State of Health (SOH) is continually calculated and reported. The SOH is based on battery pack usage and can predict end of life of the battery pack.

Protections and fault management: Over 25 fault conditions are continually monitored and status reported through RS-232 diagnostic communication. Alarm thresholds are configurable with both warning and shutdown levels.

Alarms include: cell undervoltage and overvoltage, low and high cell temperature, battery pack over-charge and over-discharge, short circuit, charging overcurrent, discharging overcurrent, and sensor failure (voltage, temperature, and current), and others.

Controller memory can record and store up to 1000 alarm events, each containing up to 64 data points.

IAR system (Intelligent Automatic Reconnect) monitors fault conditions and, unlike competitors' products, will automatically reconnect the battery pack when it is safe to do so.

Solid state relays are used to isolate the battery from the system in extreme conditions. While engaged the relay is capable of conducting 50 A continuous current in charge or discharge, and over 100 A peak current. The relay can withstand voltages of greater than 100 V.

ASCT (Adaptive Smart Connect Technology):

allows the relay to close with resistive

loads, capacitive loads, and combinations of

both. Allowing for greater connectivity than

many competitors products.

Passive balancing eliminates cell-to-cell imbalance by discharging energy at 50 mA from the cells with the highest charges. This maximizes battery capacity, extending operational runtime and battery lifetime by ensuring all cells are charged completely and equally.

Configurable, isolated RS-485 communication with external components such as displays, monitoring devices, intelligent power supplies, and other diagnostic equipment. The signal has 2.5 kV RMS signal and power isolation, and > 25 kV/µs common-mode transient immunity.



4

Reliable BMS power input can be from 25-64 V and is directly powered from the battery pack. The onboard power input regulation has high voltage, low voltage, and reverse voltage protection, as well as high voltage transient, current injection, and load dump immunity.

Battery current monitoring with an onboard high precision current sensor ensures accurate SOC calculations.

BMS controller temperature monitoring.

High-power driver can control fans, pumps, heaters, and other components for battery thermal management. Control is based on configurable high and low temperature operating limits.

Every cell’s data for temperature, voltage, and current lifetime are logged in the controller and may be useful for troubleshooting and warranty purposes.

Cell balance circuitry has self-test capability to guarantee proper BMS operation and battery pack performance.

Low-power mode: In this mode the BMS uses as little as 6 mA of power. When powered off the consumption drops to 60 µA.

In-system firmware upgrading with JTT software available via diagnostic RS-232 port.

With the JTT software tool on a PC or laptop connected to the diagnostic RS-232, battery and cell information and diagnostics are available in real-time for viewing and exporting.



5

6. BLOCK DIAGRAM

Figure 2. Controller Block Diagram



6

7. TYPICAL APPLICATION

The T-Series product line is typically used on low voltage (25-64 V) battery packs that contain 16 lithium-ion cells in series. The T-Series BMS is designed for use with battery packs for backup power applications, primarily for telecom wireless base stations. Depending on the specific application the BMS will be configured differently. The most

common accessories are heaters, fans, and other thermal management devices.

The following is an example of a T-Series BMS used on a 48 V battery pack made up of 16 cells used for backup power. This example includes a fan powered via the high-power driver which is activated in the event of high pack temperature.

Figure 3. T-Series BMS controller connected to 48 V, 16 cell LFP battery pack for backup power supply.



7

8. ELECTRICAL CHARACTERISTICS

PARAMETER MIN TYP MAX UNITS

Supply Power Specifications

Supply Voltage (V main) 25 48 64 V

Supply Current, Active Mode ( @ 48V ) 12 mA

Supply Current, Low-Power Mode ( @ 48V ) 6.0 mA

Supply Current, Off Mode ( @ 48V ) 60 μA

Solid State Relay Specifications

Current Continuous 50 A

Current Pulse 100 A

Voltage 100 V

Cell Voltage Monitoring Specifications

Measurement Resolution 1.5 mV

Measurement Offset -0.5 0.5 mV

Measurement Gain Error -0.12 0.12 %

Cell Voltage Range 0 5 V

Cell Monitoring Current (In/Out Pins Cell 1 to Cell 16)

Active Measuring -10 10 μA

Leakage 1 nA

Cell Monitoring Supply Current (In Cell1 Out Cell 16)

Active Measuring 620 780 1000 μA

Leakage 6 18 μA

Measurement Period 50 ms

Cell Temperature Monitoring Specifications

Measurement Resolution 0.1 °C

Measurement Accuracy 1.0 %

Cell Temperature Range -100.0 100.0 °C

Cell Balancing Specifications

Passive Balancing Current 50 60 mA

Isolated RS-232 Communication Specifications

Rx Input Voltage Range -25.0 25.0 V

Rx Input Threshold Low 0.8 1.4 V

Rx Input Threshold High 1.9 2.4 V

Rx Input Resistance 3 5 7 kΩ

Tx Output Voltage ±5 ±5.4 V

Tx Short-circuit output Current ±35 ±60 mA

Data Rate 57.6 Kbps

ESD Protection (HBM) ±15 kV



8

Isolated RS-485 Communication Specifications

Rx Input Resistance 96 125 kΩ

Rx Termination Resistance Enabled 108 120 156 Ω

Rx Differential Input Threshold Voltage (A-B) -0.2 0.2 V

Rx Input Failsafe Hysteresis (B=0) 25 mV

Rx Input Failsafe Threshold (B=0) -0.2 -0.05 0 V

Tx Differential Output Voltage 2.1 5 V

Data Rate 9.6 115.2 Kbps

ESD Protection (HBM) ±15 kV

Battery Voltage Monitoring Specifications

Range (Low Range Configuration) 0 60 V

Resolution (Low Range Configuration) 1.0 mV

Accuracy 0.5 %

Current Sensor Specifications

Measurement Range (Charge/Discharge) -75 90 A


Measurement Resolution (high/low current) 3.1 0.4 mA

Sampling Rate 1 ms

Onboard Temperature Sensor Specifications

Measurement Resolution 0.1 °C


Cell Temperature Range -45.0 100.0 °C

High-Power Driver Specifications

Current Output 5 A



9

9. APPLICATION INFORMATION

MODES OF OPERATION

The T-Series controller has two modes of operation: Active mode and low-power mode. In active mode the controller is completing all required tasks. Low-power mode is a power saving mode where all cell voltage and temperature monitoring circuits, external sensors, and all peripherals may be turned off. If required, only the controller core and external communications (RS-485 and RS-232) will remain operational. The controller can be configured to switch between active mode and low-power mode by digital input, RS-485, RS-232, communication command, or timeout event. The functions working in low-power mode may be customized for a particular application. In some applications, minimal power consumption is of primary importance, so all monitoring activities and peripherals are powered down. In other applications, it may be more important to keep large capacity cells balanced, so cell voltage monitoring and cell balancing circuitry may remain operational in low-power mode. CELL MEASUREMENT

Cell voltage measurement is one of the most important parts of the T-Series BMS. Although the voltage does not indicate the charge in a lithium battery, the voltage is critical to calculating the state of charge. The T-Series BMS has cell voltage monitoring with a resolution of 1.5 mV, with ±0.12 mV offset, and only ±0.5% error. CELL INPUT PROTECTION

The cell voltage monitoring inputs are capable of measuring 0-5 V. However, input protection has been added to protect the BMS controller and ensure that cell discharging is minimized if any voltage inputs are wired incorrectly. Each cell input also has reverse voltage and high voltage protection to prevent equipment damage in the event of incorrect wiring.

If cell input protection is triggered because of incorrect wiring, the protection will automatically reset itself once the cell input connector is unplugged and voltage is removed from the input pins. This will protect the BMS from damage and minimize cell discharge; however some cell discharge will be present if cells are incorrectly wired. Care must be taken to ensure that all cell voltage inputs are wired correctly. PASSIVE CELL BALANCING

Cell balancing is achieved by discharging energy from the highest charged cells. Cell balancing is required to keep all cells within the battery pack equally charged. This ensures that cells with slightly weaker performance are not degraded further by over-charging or over-discharging during operation. A well balanced battery pack will have higher capacity and longer runtime than an unbalanced one. Depending on cell voltage the passive balance circuitry will discharge between 50-60 mA from a balancing cell. The controller also monitors internal circuit temperature and may limit cell balancing when operating in extreme high temperatures. ALARM DEFINITIONS AND REPORTING

Over 25 alarms are evaluated at 10 times per second to ensure safe battery operation, and to maximize battery pack performance and lifetime. The list of alarms is configured for different battery cell types and battery applications. Alarm severities are divided into warning and protect levels. A warning alarm indicates that the battery is operating outside of normal performance parameters, and that there may be a problem with the battery pack. The BMS will not take any emergency action due to a warning alarm. This condition is normally communicated externally. A protect alarm indicates that the battery pack is operating well outside of the normal parameters



10

and may be causing a safety hazard. The BMS will disconnect the battery pack from the system in the event of a protect alarm. Alarm thresholds can be customized for your application or operate with the default settings. Alarm status may be reported via RS-485 or RS-232 communication. CURRENT SENSOR

The T-Series controller has a bi-directional shunt current sensor with a 16-bit analog front end that allows the BMS to monitor the current in and out of the battery with high accuracy and fast response time. DATA LOGGING

The controller logs lifetime histograms of temperature, voltage and current of every monitored cell in the controller memory. In addition, alarm data is also logged: the controller is capable of logging up to 1000 alarm records, each with 64 data points. This data can be useful for troubleshooting and warranty purposes.

Battery cell serial numbers can be set and stored in the controller during pack assembly to be used for cell tracking. DIAGNOSTIC / FIRMWARE UPGRADING RS-232

The isolated RS-232 bus is configured for 57.6 Kbps and is used for diagnostics and upgrading firmware. This interface is meant to be connected to your laptop or PC. The JTT Firmware loader is used to upgrade BMS firmware. BMS Link can be used to monitor and log all battery and BMS data for troubleshooting and servicing. BATTERY PACK MONITORING

Connecting a laptop or PC with the BMS Link software to the diagnostic RS-232 allows real-time battery pack monitoring.

DEFINITION OF INDICATOR LEDS

PACK STATE PROTECT/ALARM/ NORMAL

RUN ALM SOC LED (GREEN)

OFF OFF OFF OFF OFF OFF OFF

LOW POWER NORMAL FLASH OFF OFF OFF OFF OFF

WARNING OFF FLASH OFF OFF OFF OFF

CHARGING

NORMAL ON OFF SHOW SOC (with FLASH)

WARNING ON FLASH

PROTECT OFF ON OFF OFF OFF OFF

DISCHARGING

NORMAL FLASH OFF SHOW SOC (no FLASH)

WARNING FLASH FLASH

PROTECT OFF ON OFF OFF OFF OFF



11

10. TYPICAL WIRING

System Wiring

Figure 4. T-Series BMS controller connected to 48 V, 16 cell LFP battery pack for backup power supply.



12

User Wiring

Figure 4. T-Series BMS controller user wiring detail.

RS-485 Notes:

120 termination for the RS-485 interface is configurable available in the BMS settings.

The RS-485 connections are equivalent and are available for convenient multi-drop

connection.



13

11. CONNECTORS AND PIN OUT

Connector Connector P/N Contact P/N Hand Crimp Applicator

Banks 1-4 JST

XADRP-08V

JST

SXA-01T-P0.6 (loose) (20-24 AWG)

JST

WC700M or

YC-701R

RS-485 20020013-D031B01LF

(20-24 AWG)

NONE

(Screw Terminal)

RS-232 20020013-D021B01LF

(20-24 AWG) NONE

(Screw Terminal)



14

Connector Banks 1-4 – Cell Voltage and Temperature Monitoring

Header Plug

Bank 1

Pin Tag AWG Description

1 Cell 1 negative 20-24 Cell 1 negative terminal voltage input

2 Cell 1 20-24 Cell 1 positive terminal voltage input

3 N/C -- 4 Cell 2 20-24 Cell 2 positive terminal voltage input

5 TS1b 20-24 Bank 1 temperature sensor


7 TS1a 20-24 Bank 1 temperature sensor


Bank 2










15

Bank 3








Bank 4








RS-232 Interface

Header Plug

RS-232


1 Rx 20-24 Receive line

2 Tx 20-24 Transmit line

3 Gr 20-24 RS-232 ground



16

RS-485 Interface 1 and 2

Header Plug

RS-485-1, RS-485-2


1 B 20-24 Differential B line

2 A 20-24 Differential A line



17

12. SIZE AND MOUNTING

All dimensions are in mm

All mounting holes are 3.5 mm with 7 mm pads Soldered cable lengths and connectors are customizable by customer request 3D CAD file available for connector and cut-out locations

Figure 5. T-Series BMS controller front view with dimensions and mounting hole coordinates.

Figure 6. T-Series BMS controller after installation in battery pack casing.



18

Figure 7. T-Series BMS controller front side mounting clearance.

Figure 8. T-Series BMS controller side view showing back side clearance requirements and board

thickness.



19

13. BMS LINK SOFTWARE

Monitor and diagnose battery pack problems from your PC or laptop in real-time.

The most comprehensive, battery integrated monitoring, logging and control software.

BMS Link software is available for all JTT BMS products.

Windows XP, 7

Multi-page layout displays battery data in numerical and graphical form.

Cell voltages, temperatures, SOC, SOH, cell DCRs, balancing status, alarm status, battery voltage, battery current, and more available in real-time.

Service Mode available for additional data, and forced control of all battery components such as fans, heaters, relays, cell balancing on/off.

Controller identification by serial number and firmware version.

Cell identification and tracking by serial number with cell lifetime data for warranty and troubleshooting.

Export and save data log files to Excel spreadsheets.

Updates with all cell and battery pack information every 100 ms.

Alarm status information.

jtt electronics t-series bms data sheet · t-series bms data sheet commercial confidential...

Documents