NPS2400
User’s Manual
Rev. 3.0
– 17.02.2015
Page 17/38
4.4 Maintenance
The FAN should be checked periodically (recommended: every 6 moths). Dirty fans can be cleaned using compressed air
generated by a vacuum cleaner from outside of the unit. Do not use high pressure air flux, it can damage the unit.
Optionally a
maintenance reminder
can be activated by factory (see §6.6.20). The remainder will be activated after a user
definable hours of operation. To acknowledge the reminder the user must keep the button up and the button down pressed for
more then 3 second.
5 Operating modes
NPS2400 power supply has 3 different operating modes, user selectable (see §6.4.12).
Overboost
(OB)
Constant current limit
(CC)
Battery charger
(BC- available
only on “-24” and “-48” models)
5.1 Overboost mode (default)
NPS2400 in
Overboost mode
can provide a temporary power boost up to 150% (3600W) of its rated power for a maximum of 5
seconds. This mode is suitable for powering loads with high inrush current such as motors or highly capacitive loads. It also
helps in blowing fuses of failed loads and separate those from other active loads connected in parallel. The output U/I behaviour
in
OB
mode is presented in Figure 17.
Iout
U
o
u
t
Unom
Inom
Hiccup cycle
0.1*Unom
1.5*Inom
H
ic
c
u
p
c
y
c
le
a
ft
e
r
5
s
e
c
Figure 17 Output voltage vs. current characteristics in Overboost mode
As soon as the output current becomes > Inom a timer is started; when the timer elapses (5 s) the output is shut OFF and kept
OFF for 10 seconds (hiccup cycle
– 5 s ON/10 s OFF).
In case of a
“dead short circuit” on the output (Uout<0.1*Unom) the maximum current is still limited at 1.5*Inom, but the output
shuts off after about 100 ms entering a hiccup cycle.
