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IM-ENG-114/GB
7.3 STARTING UP
After having carried out all preliminary controls it is then possible to utilize the PS1550.
It would be advisable to measure total current delivered at system output (utilizing a continuous ammeter) so as to
be aware of the applied load and margins for future expansion.
In full load conditions it is necessary to verify ventilation system efficiency: see curve in Fig. 1.
P
N
1
P
N
2
+24V
COM
PS1550
2500 Vrms
~
P
N
1
P
N
2
+24V
COM
PS1550
500 Vdc
Fig. 11.
Isolation Testing Inputs-Ground.
Fig. 12.
Isolation Testing Output-Ground.
8. MAINTENANCE
Maintenance operations must be carried out by qualified personnel.
Remember that certain parts of the power supply unit generate voltage up to 400 V, a potentially lethal situation. It
is therefore strictly prohibited to remove any type of protection or to access internal parts of system when connec-
ted to mains. All Modules are extractable and can be individually inspected without having to open the chassis.
Improper connection of input Lines may provoke serious damage to system and associated equipment.
Verify that grounding connections are efficient to avoid risk of electrical shock.
Each line Module contains capacitors with a total capacity of 3300µF for Type-115, 1500µF and Type-230: such
components loaded at working voltage accumulate lethal energy. Before extracting Modules it is therefore neces-
sary to first disconnect them from Mother Board, then pull outward without actually extracting Modules so that they
are only extracted 1 cm and leave them in this position permitting internal bleeder resistors to completely discharge
capacitors.
The Power Modules also present input capacitance and require waiting at least half a minute before their extrac-
tion. In order to function correctly the system must be adequately cooled. It is extremely important that all air filters
are kept clean and periodically check fan status (verify that air flow inlet/outlet are free from obstructions due to du-
st or grime, verify that fan rotation is correct, etc...). The fan box is readily accessible for inspection by extracting it
from its housing and disconnecting wiring from mother board.
If steady accumulation of dust forms on Power Module dissipators, it is advisable to clean them by compressed air
or after their extraction from rack, by brush.
