Extech Instruments BT100 User manual

User Manual
Battery Capacity Tester
Model BT100
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AdditionalUserManualTranslationsavailableatwww.extech.com

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Introduction
Thank you for selecting the Extech Model BT100. The Battery Tester is designed for measuring the
internal resistance and output voltage of batteries including lead storage cells, nickel-cadmium
batteries, lithium-ion batteries, and nickel-metal hydride batteries.
This device is shipped fully tested and calibrated and, with proper use, will provide years of reliable
service. Please visit the Extech Instruments website (www.extech.com) to check for the latest version
of this User Guide.
Features
Accurate results are achieved using a four-terminal measurement method that eliminates lead
and contact resistance.
1kHz test current with up to 10µresistance resolution.
Dual display simultaneously indicates the internal resistance and the battery voltage.
Comparator function with storage of up to 99 sets of resistance and voltage data for battery
deterioration characterization.
Pin type and alligator type 4-terminal Kelvin leads for quick and accurate resistance
measurements.
Memory capacity to store up to 999 (manual datalogging) or 9600 (automatic datalogging) data
points.
Supplied RS232 PC port and Windows compatible software.
Safety
International Safety Symbols
This symbol, adjacent to another symbol or terminal, indicates the user must refer to the
manual for further information.
This symbol, adjacent to a terminal, indicates that, under normal use, hazardous voltages
may be present
Double insulation

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Meter Description
1. Power button: Power ON/OFF
2. R READ button:
Press R button to start manually logging
readings.
Press R READ button again to stop logging.
3. M MEMORY button:
Under the manual logging mode, the tester
stores a single set of logged readings to the
memory by pressing
M MEMORY button.
Press and hold M MEMORY button for 2
seconds to enter continuous (automatic) logging
mode. Press again to stop logging.
4. V-RANGE button: Select the voltage range. (4V,
40V)
5. HOLD button:
Press HOLD to freeze or unfreeze the displayed
reading.
Press and hold the HOLD button for 2 seconds
then release, to enter the interval time (sample
rate) setting for continuous data logging. Set from
1 to 255 seconds. Press Set button to save and
exit.
6. Ω- RANGE button: Select the resistance range. (40m, 400m, 4, 40)
7. REL button:
Press to move the cursor to the right.
Press REL (Relative) to zero the reading.
8. button: Press to increase the displayed value.
9. SET button:
Press SET to switch the comparator mode on or off.
Press and hold the SET button for 2 seconds to enter the comparator-setting mode. Press
again to store the setting in memory.
10. button: Press to decrease the displayed value.
11. Button:
Press to move the cursor to the left.
Press to switch the audible tone on or off.
12. RS-232 connector: PC interface connector.
13. – Input jack: Black test lead plug connection.
14. + Input jack: Red test lead plug connection.
15. LCD display (LED test status indicators are located below the LCD display)
16. AC adaptor input

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Display Description
1. Measured resistance reading (or High/Low resistance limit when setting up the comparator)
2. Measured voltage reading (or High/Low voltage limit when setting up the comparator)
3. The comparator set number (there are 99 sets total)
4. The memory location for manually logged data.
Symbols:
m: Milliohm (resistance)
V: Voltage
HOLD : Hold function (display freeze)
COMP : Comparator function enabled
: Low-Battery
:Beeper enabled
DATA R : Manual datalogging enabled
M : Continuous datalogging enabled (flashes each time data is stored)
INTV: Interval time setting for the continuous datalogging function. (1 to 255 seconds)
COMP.SET : Comparator settings mode
HIGH: High limit setting (threshold) for the comparator
LOW: Low limit setting (threshold) for the comparator
LED Test Status Indicators
PASS (green LED): Battery is good (within the tolerances of the comparator’s preset limits)
WARNING (yellow LED): Battery is beginning to deteriorate
FAIL (red LED): Battery has failed
The LED status indications listed above are active when the High/Low comparator limits for internal
resistance and the comparator threshold value for voltage are properly configured.

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Operation
Preparation and Safety
The following safety information must be observed to ensure maximum personal safety during the
operation of this tester.
To avoid electric shock when replacing the batteries: Disconnect the test leads from the device
under test before attempting to replace the batteries.
Check the battery polarity carefully when inserting the batteries. Refer to the battery
replacement section (under Maintenance) later in this User Guide.
Be sure to dispose of used batteries properly.
WARNING
Do not attempt to measure DC voltage exceeding 50V.
Do not attempt to measure AC voltages; this could result in personal injury or
damage to the unit.
To avoid personal injury and/or damage to the unit, do not attempt to measure
the voltage of a generator. This will result in an AC voltage being applied to
the voltage generating output terminals.
After measuring a high voltage battery, and before continuing to measure a
low voltage battery, short the measurement leads by touching the lead tips
together. This will discharge the DC-elimination capacitor (connected across
the leads); otherwise a dangerous condition can exist where an excessive
voltage may be applied to the low voltage battery.
Test Leads
Two sets of test leads are supplied with the meter. Both sets provide four (4) terminal Kelvin
connections which eliminate lead resistance and probe contact resistance. The application will dictate
whether the alligator type or the press-probe type should be used.

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Testing Procedure
Connect the red test lead to the “+” jack and the black test lead to the “-” jack.
1. Press the Power button to switch the tester ON.
2. Use the V-RANGE or -RANGE buttons to select the desired Voltage or Resistance range.
3. Perform a REL Zero adjustment (see next section) each time the range is changed.
4. Connect the red test probe to the positive battery terminal, and the black test probe to the
negative battery terminal.
5. Read the battery’s internal resistance and the DC voltage directly on the meter’s display.
Note: When the measured DC voltage or battery internal resistance value is over range, “OL” is
displayed. When the AC test current faults “- - - -” will be displayed.
REL Adjust (ZERO)
The REL function zeros the selected range. The reading displayed when the REL button is pressed
will be taken as zero and will be used to ‘offset’ subsequent measurements.
1. Short the four (4) probe tips of the red and black test leads as shown in the accompanying
diagrams.
2. Press the REL button and the display will show the ‘R’ icon and the resistance and voltage
values will zero.
3. Connect the test leads to the battery to be tested.
4. The REL zero adjust must be performed each time the range of the meter is changed, the test
leads are swapped, or after switching between resistance and voltage tests.

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Comparator (99 sets)
The comparator function compares the measured values with preset High and Low limit values for
internal resistance and threshold voltage level, and determines the range that the measurement
should fall into. Then, according to the following conditions, switches ON the corresponding LED,
and sounds an audible alert as shown in the table below for the WARNING and FAIL conditions.
Comparator Settings
1. Press and hold the SET button for 3seconds then release, the display will show COMP.SET
indicating the comparator mode is enabled.
2. Use the or button to change the comparator number from 01 up to 99.
3. Use the V-RANGE or Ω-RANGE buttons to set the desired voltage and resistance measurement
range.
4. Press once, the LOW icon and the left two digits of the low limit resistance will be flashing.
(Use the & buttons to select the desired value.)
5. Press once, the right two digits of the low limit resistance will be flashing. (Use the
and buttons to select the desired value.)
6. Press once, the HIGH icon and the left two digits of the high limit resistance will be flashing.
(Use the and buttons to select the desired value.)
7. Press once, the right two digits of the high limit resistance will be flashing. (Use
the and buttons to select the desired value.)
8. Press once, the left two digits of the threshold voltage will be flashing. (Use the 
and buttons to select the desired value.)
9. Pressonce, the right two digits of the threshold voltage will be flashing. (Use the 
and buttons to select the desired value.)
10. Repeat step 2 to step 9 to set the next comparator number.
11. Press SET again to exit the comparator setting mode.
Comparator Table
Resistance
Voltage
Low limit resistance High limit resistance
Lo Middle Hi
Voltage Lo
Comparison
Value Hi
WARNING
Beeper
WARNING
Beeper
FAIL
Beeper
Pass WARNING
Beeper
FAIL
Beeper
Comparator Start / Stop Controls
1. Press SET to activate the comparator function, the COMP indication will appear on the display.
The comparator will operate once measurements are taken.
2. Use the and buttons to select the desired comparator number. The selected comparator
number remains in memory even when the power is switched off.
3. Press to set the audible alert ON, the indication will appear on the display, and the
audible tone will sound with a WARNING or FAIL result. Press again to disable the audible
alert.
4. Press SET again to switch off the comparator function.

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Datalogging
Manual Data Logging (999 sets)
1. Log readings one at a time to the internal memory by pressing the MMEMORY button.
“DATA M NO XXX” will appear on the LCD for one second to indicate the memory location.
2. Press RREAD button to review logged readings. The display will show “DATA R NO XXX”.
3. Use the and buttons to scroll the logged readings.
4. Press RREAD again to discontinue viewing the logged readings.
Continuous Data Logging
1. Press HOLD for 2 seconds, then release, and the display will show the INTV icon.
2. Use the or button to select the desired interval time (datalogging sample rate) from 1
second to 255 seconds.
3. Press SET to save and exit the interval time setting mode.
4. Press and hold MMEMORY for 2 seconds to enter the continuous (automatic) logging mode, the
display will show the Micon.
5. The Mwill flash each time a reading is stored.
6. Press MMEMORY again to exit the continuous datalogging mode.
7. Data stored using the continuous datalogging mode cannot be read directly on the tester’s
display, it must be downloaded to a PC using the supplied software.
Clearing the Datalogger Memory
When the internal memory is full, the Full icon will appear on the display and datalogging will stop.
1. Press to switch OFF the tester.
2. Press and hold the MEMORY button, and while continuing to hold the MEMORY button, press
the button. The display will show the CLr icon and all datalogged readings will be cleared from
memory.

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Specifications
Resistance measurement method Four (4) terminal Kelvin connections
A/D conversion Dual slope
Displays Dual LCD for measurements and programming icons
Three (3) test status LEDs
Datalogger Sampling rate 1 to 255 seconds (interval time between logged readings)
Open-circuit terminal voltage 3.5Vpp max
Measurement frequency 1KHz
± 10%
Input over range “OL” display
Low battery indication display
Test current fault detect “- - - -” display
Auto power off After approximately 30 minutes
Zero (Relative) function Circuit offset voltage is displayed as 0V
Hold function Display freezes
Audible Alarm function Audible alert for Warning and Failure conditions (can be set
ON or OFF)
Comparator settings Resistance High/Low limits and Voltage threshold point
Number of comparator configurations 99 sets
Comparator output Test status LEDs for Pass (green), Warning (yellow), and Fail
(red) results (audible tone for Warning and Fail conditions)
Resistance
Voltage Lo IN Hi
Lo Warning Warning Fail
Hi PASS Warning Fail
Manual Datalogging memory 999 sets can be stored in meter’s internal memory
Continuous (automatic) Datalogging 9600 sets can be stored in meter’s internal memory
Operating conditions 0
° to 40 °C (32 to 104°F) 80%RH (non-condensing)
Storage conditions -10
° to 50 °C (14 to 122°F) 80%RH (non-condensing)
Power source Six (6) ‘AA’ 1.5V batteries; Optional 9V AC adaptor
Maximum power consumption 1.0VA
Maximum continuous operation 7 hours approx.
Altitude 2000m max.
Dimensions 250 x 100 x 45mm (9.8 x 3.9 x 1.7”)
Weight 500g (1.1 lbs.) approx. (including batteries)
Accessories Test Leads and batteries
Optional equipment AC adaptor (9V output)

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Electrical Specifications
To ensure accuracy the ambient temperature should be 23
°C ± 5 ° with a humidity of 80% RH
(maximum) non-condensing. In addition, perform a Zero adjustment after each range change.
Resistance measurements
Temperature coefficient: (
± 0.1% rdg ± 0.5digits)/ °C
Measurement frequency: 1KHz
± 10%
Measurement burden voltage: 1.5mVAC
Range Resolution Measurement current Accuracy
40m10µ37.5mA approx.
± (1% reading ± 10digits)
400m100µ3.75mA approx.
41m375µA approx.
4010m37.5µA approx.
Voltage Measurements
Temperature coefficient: (
± 0.1%rdg ± 0.5digits)/ °C
Range Resolution Accuracy
4V 1mV
± (0.1% reading ± 6digits)
40V 10mV
Maximum Input Voltage: 50VDC maximum
No AC voltage input permitted
Maximum voltage allowed between input terminals and ground: 60VDC/AC
DANGER
Do not exceed the maximum permissible input voltage (60VDC/AC) to the measurement terminals.
This could result in personal injury and/or damage to the unit.