Some of the ML-2 controllers from DEIF A/S contains a Lithium-cell as voltage supply for a memory circuit. This Lithium cell is designed to last the expected lifetime of all other electronics in the controller. Though it seems that all other electronics of the controllers typical last longer than expected and based on this we recommend a preventive update of the Lithium cell.

The consequences of a power down/up of a controller with a worn-out Lithium cell is a reset to factory settings of all settings and options. Newer SW detects this situation and block the controller from power up.

The controller is designed to last for the below mentioned period – the time is dependent of the environmental temperature as shown in the table. DEIF recommend exchanging the Lithium cell as a preventive precaution within 80% of the expected lifetime.

Table with lifetime expectation based on environmental temperature:

Temp.                                         Lifetime              Prev. replacement

Temp. < 40°C                             10 years             8 years
40°C < Temp. < 50°C                  5 years              4 years
50°C < Temp. < 60°C                 2½ years            2 years
60°C < Temp. < 70°C                15 months           1 year


This recommendation relates to the follow controllers:

AFC Plant Management SW version 1.00.0

AGC Plant Management SW version 3.50.1

AGC-2 SW version 2.00.0

AGC-3 SW version 3.00.0

AGC-4 SW version 4.00.0

ASC Plant Management SW version 5.00.0

BGC-2 SW version 1.00.0

GPC-2 SW version 1.26

GPC-3 SW version 3.00.0

GPU-2 SW version 1.26

GPU-3 SW version 3.00.0

MDR-2 SW version 1.00.0

PPM-3 SW version 3.00.0

PPU Power Management (PPM-2) SW version 2.50.5

PPU-2 SW version 1.26

PPU-3 SW version 3.00.0

Please follow link below to get guide on how to do the battery replacement:
General: How can I replace the battery without loss of data and settings ?