Appendix F: Battery Test Procedure - iRobot Roomba 570 Service Manual

Appendix F: Battery Test Procedure

Using Battery Voltage Tester
To measure the voltage across a Roomba 500 series battery, to measure voltage across a 5-Ohm resistor, and to measure the
Objective :
thermistor resistance.
Equipment : Battery Voltage Tester, Multimeter, and fully charged battery under test.
Method
Fully charge battery with Roomba and latest software. Remove battery from Roomba
1.
To measure voltage across the fully charged battery, set the multimeter to measure DC VOLTAGE (V), and plug the multimeter
terminals to the positive (+) and negative (-) terminals of the charge barge.
2.
Failure if reading is less than 14.5V.
To measure the voltage across a 5 Ω resistor, follow step 1 (set the multimeter to measure DC VOLTAGE), and press the 5-Ohm
resistor push button (Caution: Do not press button for more than a few seconds to avoid overheating of the load.)
3.
Failure if voltage drop is more than 2 Volts.
Make sure battery is not hot from charging and needs to be equilibrated to room temperature. To measure the thermistor resistance
value (thermistor contact to ground contact), set the multimeter to measure RESISTANCE (Ω), and plug the multimeter terminals to
4.
the thermistor terminal and the negative (-) terminal.
Failure if not within specs in table below.
Ambient Room Thermistor
Temp Min (K Ohm)
10 to 17.5 C 12.0
17.6 to 25.5 C 8.5
25.6 to 33.5 C 6.0
33.6 to 41.5 C 4.3
Thermistor
Max (K Ohm)
21.8
15.5
11.0
7.8
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