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MULTICAL® 803
144
Kamstrup A/S · Technical description · 5512-2360_A1_
GB
_02.2019
10.2
Lifetime of the backup battery
The backup battery lifetime depends on factors like ambient temperature and meter configuration. An indication of
the battery lifetime is thus a realistic estimate. In general, the battery lifetime of the backup battery can be
considered from two scenarios and in two different applications. Either the calculator is operated by battery only
from the day of delivery or the backup battery is used as backup battery in case of mains failure within the 10-year
replacement interval. The estimated lifetime of the backup battery in MULTICAL® 803 appears from the table below.
Function on battery
Battery operation from
delivery
Backup operation within
the replacement interval
(10 years)
Calculator
1
Up to 6 years
Up to 2 years
Calculator
1
+ Module 10 - Data +
Pulse inputs
Up to 3 years
Up to 1 years
Calculator
1
+ Module 20 - M-Bus +
Pulse inputs
Calculator
1
+ Module 30
2
- wM-Bus +
Pulse inputs
1
Basic meter function (V1, V2, t1, t2, t3, t4 and display without backlight)
2
Note that the battery lifetime for wM-Bus depends on the selected datagrams. See “Logger profiles and datagrams,
5512-2245” for more information
Modules that are not shown in the overview should not be used on module slot 1 during backup operation.
Conditions for above calculations of battery lifetime:
-
Wall-mounted calculator (tBAT < 30 °C)
-
Data reading: Max one reading per hour
-
M-Bus reading: Max one reading every 10 seconds
-
Display on (LCD ON), no backlight
-
The connected ULTRAFLOW® 54 flow sensors
have an average flow ≈ qp/4