User manual

76 Rockwell Automation Publication 1756-UM001O-EN-P - October 2014
Chapter 3 Start Using the Controller
Estimate 1756-BA2 Battery Life After Warnings
Use this table to estimate the battery life after the low-battery warnings are
indicated. Use these times even if the controller does not have power because
there is a small power-drain on the battery.
IMPORTANT
When you power up the controller, see if there is a low-battery warning. If
you get a low-battery warning for the first time, you have less battery life
than this table shows. While powered down, the controller still drains the
battery but it cannot give the low-battery warning.
Temperature 2.54 cm (1 in.)
Below the Chassis, max
Power Cycles Battery Life After the BAT Status Indicator Turns Red (worst case)
Project Size
1 MB 2 MB 4 MB 8 MB 16 MB
0…20 °C (32…68 °F) 3 per day 26 weeks 18 weeks 12 weeks 9 weeks 5 weeks
1 per day 26 weeks 26 weeks 26 weeks 22 weeks 13 weeks
1 per month 26 weeks 26 weeks 26 weeks 26 weeks 26 weeks
21…40 °C (69.8…104 °F) 3 per day 18 weeks 14 weeks 10 weeks 8 weeks 5 weeks
1 per day 24 weeks 21 weeks 18 weeks 16 weeks 11 weeks
1 per month 26 weeks 26 weeks 26 weeks 26 weeks 26 weeks
41…45 °C (105.8…113 °F) 3 per day 12 weeks 10 weeks 7 weeks 6 weeks 4 weeks
1 per day 15 weeks 14 weeks 12 weeks 11 weeks 8 weeks
1 per month 17 weeks 17 weeks 17 weeks 17 weeks 16 weeks
46…50 °C (105.8…113 °F) 3 per day 10 weeks 8 weeks 6 weeks 6 weeks 3 weeks
1 per day 12 weeks 11 weeks 10 weeks 9 weeks 7 weeks
1 per month 12 weeks 12 weeks 12 weeks 12 weeks 12 weeks
51…55 °C (123.8…131 °F) 3 per day 7 weeks 6 weeks 5 weeks 4 weeks 3 weeks
1 per day 8 weeks 8 weeks 7 weeks 7 weeks 5 weeks
1 per month 8 weeks 8 weeks 8 weeks 8 weeks 8 weeks
56…60 °C (132.8…140 °F) 3 per day 5 weeks 5 weeks 4 weeks 4 weeks 2 weeks
1 per day 6 weeks 6 weeks 5 weeks 5 weeks 4 weeks
1 per month 6 weeks 6 weeks 6 weeks 6 weeks 6 weeks
EXAMPLE
Under these conditions, the battery lasts at least 20 months before the BAT
status indicator turns red:
• The maximum temperature 2.54 cm (1 in.) below the
chassis = 45 °C (113 °F).
• You cycle power to the controller three times per day.
• The controller contains an 8 MB project.