Thomas & Betts 9395 - Manual (Page 63)

UPS 225 - 275 kVA
User’s and Installation Guide
1027212
Revision B 3
5.3.11 Using Mechanical Bypass Switch
The operation of the integral MBS is allowed for a trained person only who is familiar with the
UPS behaviour and functions. The full UPS wiring diagram with a MBS switch is presented in
the installation part of the manual.
NOTE!
The integral MBS and Static Bypass need to supplied by the same source.
Figure 5-8. The normal positions of the MBS switches and rectifier disconnect switch (must be located in the
site wiring).
Turn UPS from normal mode to mechanical bypass
The procedure to turn the UPS to mechanical bypass switch is described below.
1. The normal start position should be following:
2. Perform transfer from normal mode to bypass mode as described in paragraph 5.3.4.
Remember to verify the transfer before proceeding the next step.
3. Turn the switch S10 from UPS (II) position to Bypass (I) position.
4. Perform LOAD OFF procedure contained in paragraph 5.3.9.
5. Turn OFF the rectifier switch to disconnect UPS rectifier input.
6. Turn OFF the Static bypass switch to disconnect UPS bypass input:
7. UPS is now in the mechanical bypass mode, see below: