Slide 23 of 28
Notes:
EXTERNAL SUPPORT APPARATUS
The C/S will normally be powered from commercial power. However, control loss at a critical phase could be disastrous at worst, and annoying and expensive at best. Therefore, an uninterruptable power supply is required. The time of operation of the C/S and what critical functions must be maintained need to be evaluated to determine if batter power alone or a backup generator is needed. In either case, a sensing system to detect power loss will switch over to a battery powered inverter. In the event a backup generator is used, the generator will automatically start, and when ready, will pick up the load. The commercial power must be monitored. When is returns, after a delay to allow transients to settle, the UPS will switch back to commercial power, shut down the generator, and recharge the batteries.