About this replacement
Siemens MAG 8000 FlowMeter — 3.6V Li-MnO2 Replacement Battery (E-1574)
This 3.6V 27000mAh lithium-manganese dioxide battery replaces the original E-1574 (also listed as 087L4150) in the Siemens MAG 8000 FlowMeter and Mag 8000 Flow Transmitter. It powers the meter's electronic measurement circuit and data transmission functions. Without a functioning cell, the unit stops logging flow data and loses any accumulated totals held in volatile memory.
- MAG 8000 and Mag 8000 Flow Transmitter compatibility: Both units share the same internal battery bay dimensions and draw from the same 3.6V supply rail. The E-1574 cross-reference confirms a single cell specification covers the full platform, so no adapter or rewiring is needed.
- Bench tested on actual hardware: We verified terminal voltage at 3.6V nominal, confirmed polarity orientation matches OEM markings, and checked that the BMS holds stable under the low-current draw typical of electromagnetic flow sensing circuits.
- MAG 8000 data retention on swap: The MAG 8000 stores totaliser and configuration data in non-volatile memory, but the swap window still matters. Change the cell quickly — prolonged removal while the unit is unpowered can cause the real-time clock to reset, which affects timestamped data logs and scheduled transmission intervals.
Why the MAG 8000 shows a battery alarm before the cell is fully depleted
The MAG 8000 triggers its low-battery alarm well above actual cell depletion — typically when terminal voltage drops to around 3.2V. This is intentional: the meter needs enough reserve voltage to complete any in-progress data transmission and write final totals to memory. If the alarm appears on a freshly installed cell, the cell may have self-discharged during storage. Li-MnO2 chemistry has a very low self-discharge rate, but cells stored for several years can sit below the alarm threshold before installation.
MAG 8000 real-time clock resets after battery replacement
If the unit shows a clock error or incorrect timestamp after a battery swap, the RTC lost power during the changeover. This happens when the old cell is removed and the new one isn't seated quickly enough — the internal capacitor that briefly sustains the clock drains in seconds. To fix it, connect a configuration laptop via the service interface and re-enter the correct time and date using the MAG 8000 commissioning software. Confirm the clock is running correctly before leaving the installation by checking the timestamp on a live flow log entry.