76 Rockwell Automation Publication 1756-UM001M-EN-P - February 2012
Chapter 3 Start Using the Controller
Check the Battery Status
When the battery is approximately 95% discharged, these low-battery warnings
are indicated:
• The BAT is solid red.
• A minor fault (type 10, code 10) is logged.
1756-BA1 or 1756-BATA Battery Life
To estimate how long a 1756-BA1 or 1756-BATA battery will support controller
memory on 1756-L6x, series A controllers, perform this procedure.
1. Determine the temperature 2.54 cm. (1 in.) below the chassis.
2. Determine the weekly percentage of time that the controller is turned on.
3. Determine the estimated worst-case battery life before and after the BAT
status indicator turns on.
4. For each year of battery life, decrease the time before the BAT status
indicator turns on by the percentage that is shown in the table.
IMPORTANT: To prevent possible battery leakage, even if the BAT status
indicator is off, replace a battery according to this schedule.
If a controller is off either one of these times:
• 8 hr/day during a 5-day work week
• All day Saturday and Sunday
Then the controller is off 52% of the time:
• Total hours per week = 7 x 24 = 168 hrs
• Total off hours per week = (5 days x 8 hr/day) + Saturday + Sunday = 88
hrs
• Percentage off time = 88/168 = 52%
If the temperature 2.54 cm (1 in.)
below the chassis is
Replace the battery within
-25…35 °C (-13…95 °F) No replacement required
36…40 °C (96.8…104 °F) 3 years
41…45 °C (105.8…113 °F) 2 years
46…50 °C (114.8…122 °F) 16 months
51…55 °C (123.8…131 °F) 11 months
56…70 °C (132.8…158 °F) 8 months