Scheduled maintenance is currently in progress. We will provide updates as necessary.
Posted Sep 22, 2025 - 08:00 UTC
Scheduled
Maintenance Window: 22nd September 2025 – 26th September 2025 - 08:00 to 18:00 every day
Location & Affected Areas: • Site: Lefdal Data Center – Norway • Impacted Area: 11B datahall
Background: Lefdal recently experienced an unexpected failure on a PLC controlling the cooling vales for POD 2 – 11B. This failure uncovered a weakness in the design of the power and relay configuration controlled by the PLC. In short, the failure caused all vales to close in this specific situation. Although this failure is regarded as very uncommon and never occurred previously, it does however result in potential loss of cooling from both system A and B unexpectedly. This is not an acceptable and must be rectified.
Solution: The solution is to rebuild the relay configuration and the way the relays are operated from the PLC for all four POD Control Switchboards. Explained in a simplified way new relays are installed and interlocked to work around the problem that can occur because of a faulty PLC controller. The new solution will prevent the valves from changing positions in the event of a faulty PLC og 24v control voltage failure. New and improved control knobs will also be installed to make it easier for LMD technicians to operate the cooling valves in a safer and more intuitive manner.
Procedure explained (for 1 of 4 PODs, same procedure for all POD’s) 1. Cooling valves for the POD is set to manual (non plc controlled) a + b cooling. 2. Remove valve actuators from the valves to avoid unwanted changes while rebuilding and testing. 3. Rebuild automation switchboard with new relays, interlock and control functions 4. Test the new configuration and verify that actuators are responding as expected and that the indicate the correct end positions (same as before, just verification) 5. Verify that valve positions do not change when simulating PLC error. Also check that 24v power failure does not affect valve position. 6. Set valve automation to A + B cooling and re-attach valve actuators to valves. 7. Switch to A cooling only. Verify positions both visually on actuators, on control panel (HMI) and BMS 8. Switch to B cooling only. Verify positions both visually on actuators, on control panel (HMI) and BMS 9. Return to A+B to complete job.
Lefdal will monitor BMS for rising temperatures or alarms. The event of problems resources are available inside the customer area for quick manual valve.
Timeline: Day 1 (Monday): POD2 Day 2 (Tuesday): POD4 Day 3 (Wednesday): POD1 Day 4 (Thursday): POD3 Day 5 (Friday): Labling, Documentation