Liebert Hipulse E - Page 122

User Manual Liebert Hipulse E Chapter 11 – ‘1+N System’
Single or '1+N' UPS System
(07/04) Page 11-9
8. When all the module keys (BP1) have been placed in the Key Exchange Box, it will be possible to release the
trapped key (BP2) from the Box. Remove the key (BP2), place it in the external Maintenance Bypass Isolator
(Q5BYP) interlock, and rotate the key. It is now possible to close the external Maintenance Bypass Switch.
9. Close the external Maintenance Bypass Isolator (Q5BYP). The Maintenance Bypass supply is now in parallel
with the UPS Static Switch supply.
10. Open the external UPS Isolator (Q4MBC). Open the external UPS Switch.
11. Open the Rectifier input power isolator Q1, the Output power isolator Q4, the bypass power isolator Q2 and the
Battery circuit breaker.
The unit will power down but the load will continue to be supplied by the external Maintenance bypass.
WARNING
WARNING: Wait 5 minutes for the internal d.c. bus bar capacitors to discharge.
WARNING
The following points will be live within the UPS:
• Terminals and busbars of the a.c. Bypass and input rectifier supply
• Bypass power isolator
• Input rectifier power isolator
Input and output terminals remain protected by a metallic cover.
WARNING
To completely isolate the UPS from the a.c. supplies, the main external power input isolator (both isolators, where
separate supplies are provided for rectifier and bypass ) should be opened.
On the primary input distribution panel, which is often located distant from the UPS area, a label should be
posted advising service personnel that the UPS circuit is under maintenance.
Your load is now powered from the external maintenance bypass system and the UPS is completely shut down.
Caution
The load equipment is not protected from normal supply aberrations when operating in the maintenance bypass
mode.
If it is necessary to perform maintenance or repairs on the UPS system, continue the procedure below.
1. Rotate and remove the key from the external UPS Isolator (Q4MBC)
2. Take the BP2 key from the UPS output isolator to the KX box (Key Exchange Box). Insert the BP2 key and
rotate it. The BP1 keys may now be released for return to the UPS modules. Refer to the wiring diagram and
check that all the power isolators within the external maintenance bypass cabinet, connected to the output of the
UPS's, are open.