IV404E Rev.000 SIEL S.p.A.
Issue date: 2017-06-05 Pag. 76 di 90 + FR
maintenance on the whole system
The sequences of operations to be carried out to place the system in maintenance bypass are described
below. The procedures vary depending on the initial state:
- All the UPS are in NORMAL OPERATION
procedure a)
the power supply to the load is not interrupted in any way
;
- whole system with output not synchronised with the by-pass line
procedure b)
the power supply to the load is interrupted
(therefore this operation should be effected only if absolutely necessary).
Procedure a)
the by-pass line is present and its frequency and voltage are suitable
the UPS display
panel indicates
NORMAL OPERATION.
1.
Pressing keys 3, 6, 4, 7, 2, 6, 3 in succession as shown on the display activates the command
for by-pass with shutdown of the inverter (the UPSs connected to the one in which the code is
inserted will be automatically configured through the parallel cable);
2.
check that the whole system switches onto the by-pass line;
3.
close all the disconnectors SWMB;
4.
open all the switches on the device (SWIN, SWOUT, SWBY and the battery cabinet
disconnectors/fuses) and keep only disconnectors SWMB (maintenance by-pass line) closed.
The control panel remains off.
N.B.: After carrying out the operations indicated above, personnel must wait around ten minutes
for the capacitors to discharge before working on the inside of the UPS.
In this situation (during the maintenance operations), any disturbance (such as a blackout) on the
UPS supply line would have an effect on the equipment powered (since the batteries are
deactivated in this state).
