Dear Customer,

In order for us to serve you better, we have to schedule the following urgent maintenance:

FROM : 8 Nov 2009 (Sun), 1000hrs
TO : 8 Nov 2009 (Sun), 1800hrs
MAINTENANCE DURATION : 8 Hours
SERVICE IMPACT DURATION : NIL

How you and your customers/users WILL be affected:
No service interruption to any equipment within 750A DC.

With parallel UPS configuration, the 2x 160KVA Socomec UPS are sharing the loads equally. In the event one of the UPS fails, the loads from the failed UPS will be transferred to the working UPS seamlessly without interrupting the loads. Furthermore, power down the UPS is not required for replacing the old batteries. The battery bank comes with an external main breaker to isolate the battery bank with the UPS. Once the battery main breaker is isolated or disconnected, the risk is further minimized. Any fault during the batteries change will not back feed to the UPS system.

Reasons for the service disruption:
The backup batteries for the Socomec UPS are near to its product life. Though these batteries are still in working condition, 1-Net is taking proactive measures to replace these batteries before the annual building maintenance scheduled on 15th Nov 2009. This approach will able to avoid unfavorable incident from happening such as not performing its duty to deliver the backup power to the UPS and critical loads during incoming mains power disruption.

Activities to be performed during service disruption:
1. Replace the entire battery bank with new batteries.
2. Tighten and torque all batteries inter-connecting links and terminals.
3. Perform battery discharge test after the batteries are fully charged up.
4. Perform an IP Thermal scanning during discharge to identify any loose cable connections and bad batteries.