Appendix A
Specifications
©
National Instruments Corporation
A-9
NI PS-15 Power Supply User Manual
Figure A-11.
NI PS-15 Efficiency and Losses
Reliability
The lifetime expectancy shown in Table A-1 indicates the service life of the
NI PS-15, and is determined by the lifetime expectancy of the built-in
electrolytic capacitors. Lifetime expectancy is specified in operational
hours. Lifetime expectancy is calculated according to the capacitor’s
manufacturer specification. The prediction model allows a calculation of up
to 15 years from the date of shipment.
MTBF (Mean Time Between Failure) is calculated according to statistical
device failures and indicates reliability of a device. It is the statistical
representation of the likelihood of a unit to fail and does not necessarily
represent the life of a product.
Efficiency vs. output current at 24 V
Losses vs. output current at 24 V
Efficiency
1
86
88
90
85
91%
100 Vac
120 Vac
230 Vac
6 A
2
3
87
89
Power Losses
0
3
9
15
18 W
120 Vac
100 Vac
230 Vac
Output Current
Output Current
6
3
0
1
2
4
5
6
12
Efficiency vs. input voltage, 24 V, 5 A
Losses vs. input voltage, 24 V, 5 A
Efficiency
260
Vac
Input Voltage
Input Voltage
91%
88.5
89.5
90.5
90.0
89.0
88.0
Power Losses
0
3
6
9
12
15
18 W
260
Vac
5
4
85
120
155
190
225
85
120
155
190
225
