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Reserve Supply
AC Supply
S3 | Maintenance |
S2 |
|
S1 | S4 |
Battery | 24/36kVA Ratings |
Contactor |
S3 | Maintenance |
Reserve Supply | S2 | S5 |
| S1 | S4 |
AC Supply |
|
|
| Battery | 50/80kVA Ratings |
| Contactor |
480Y/277V
208Y/120V
Figure 5 – Re-establishing the Utility Supply
When the utility supply returns within acceptable limits, the UPS returns automatically to normal operation mode as previously described. The rectifier now starts to recharge the battery. However, until recharge has been completed, any further mains failure will result in reduced standby times.
S3
Reserve Supply | S2 |
S1
AC Supply
S3
Reserve Supply | S2 |
S1
AC Supply
Maintenance
S4
Battery
Contactor 24/36kVA Ratings
| Maintenance |
| S5 |
| 480Y/277V |
| S4 |
| 208Y/120V |
Battery | 50/80kVA Ratings |
Contactor |
Figure 6 – Transferring the Load onto the Reserve Supply
Transfer onto the reserve line is caused by two conditions:
a)inverter stop
b)overload
In both instances the load is transferred onto the reserve without interruption. If the overload is temporary, the system will