Datasheet
QT40.241
Q-Series
24V, 40A, THREE PHASE INPUT
26.4. USING ONLY 2 LEGS OF A 3-PHASE SYSTEM
No external protection devices are required to protect against a phase-loss
failure.
DC
L1
L2
L3
open
AC
L1
L2
L3
PE
Power Supply
This power supply can also be permanently operated on two legs of a 3-
phase system. However, it is not recommended for this power class since the
supplying 3-phase network can become unbalanced.
The output power must be reduced according to the curves below when
operation on only two legs of a 3-phase system. A long-term exceeding of
these limits will result in a thermal shut-down of the unit.
A use below 340Vac with more than 30A output current can also result in a thermal shut-down.
During power-on, some start-up attempts can occur until a permanent output power is available.
EMC performance, hold-up time, losses and output ripple differ from a three phase operation. Therefore, check
suitability of your individual application.
Such use is not included in the UL approval. Additional tests might be necessary when the complete system has to be
approved according to UL 508 or UL60950-1.
The screw of the terminal which remains unused must be securely tightened.
Fig. 26-5
Output current vs. ambient temperature
Fig. 26-6
Hold-up time vs. input voltage
Ambient Temperature
Allowed Output Current for Use on only Two
Legs of a 3-Phase System
0
-25 0 20
70°C
10
20
30
40A
40 60
A
.
.
.
2
x
4
6
0
t
o
5
5
2
V
a
c
B
.
.
.
2
x
3
4
0
t
o
4
6
0
V
a
c
C
.
.
.
m
a
x
.
6
0
s
e
c
o
n
d
s
B
A
C
0
10
20
30
50ms
320 360 400 440 3x480Vac
Input Voltage
Hold-up Time for Use on only Two Legs of a
Three Phase System
24V, 20A, typ.
2
4
V
,
4
0
A
,
t
y
p
.
24V, 20A, min.
2
4
V
,
4
0
A
,
m
i
n
.
40
Fig. 26-7
Efficiency vs. output current at 24V
Fig. 26-8
Losses vs. output current at 24V
Efficiency for Use on only
Two Legs of a 3-Phase System
8 1216202428323640
A
92
93
94
Output Current
95
96%
2x400Vac
2x480Vac
Power Losses for Use on only
Two Legs of a 3-Phase System
0
4 8 12 16 20 24 28 40A
20
10
40
50
Output Current
60W
32 36
30
2x480Vac
2x400Vac
Nov. 2012 / Rev. 2.0 DS-QT40.241-EN
All parameters are specified at 24V, 40A, 3x400Vac, 25°C ambient and after a 5 minutes run-in time unless otherwise noted.
www.pulspower.com Phone +49 89 9278 0 Germany
23/27