Eaton 93PR - 6.7. Transfer the UPS from Double Conversion Mode to Maintenance Bypass Mode

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6.7. Transfer the UPS from Double Conversion Mode to Maintenance Bypass Mode
The operation of the internal MBS is allowed for a trained person only who is familiar with the UPS
behavior and functions. The full UPS wiring diagram with a MBS switch is presented in the installation
instructions.
NOTE
The integral MBS and Static Bypass need to supplied by the same source.
Transfer the UPS to Maintenance Bypass Mode:
1. The normal start position should be following:
Output
Maintenance
bypass input
Static
bypass input
Rectier input
Bypass switch
Input switch
Output switch
Maintenance bypass switch (MBS)
Figure 6-43: Double Conversion Mode
2. Perform transfer from double conversion mode to bypass mode as described in Section
6.3.3 Transfer
from Double Conversion Mode to Bypass Mode . Remember to verify the transfer before proceeding to
the next step.
3. Turn the MBS from UPS position to Bypass position.
4. Perform the LOAD OFF procedure in Section
6.3.7 UPS System and Critical Load Shutdown .
5. Turn OFF the rectier switch to disconnect UPS rectier input.
6. Turn OFF the output switch to disconnect UPS Inverter output.
7. Turn OFF the bypass switch to disconnect UPS bypass input.
UPS is now in the Maintenance Bypass Mode:
Output
Maintenance
bypass input
Static
bypass input
Rectier input
Bypass switch
Input switch
Output switch
Maintenance bypass switch (MBS)
Figure 6-44: Maintenance Bypass Mode