GE Industrial Solutions JRW450U Orca Series - Manual (Page 6)

GE
Data Sheet
JRCW450U Orca Series; DC-DC Converter Power Modules
36–75 Vdc Input; 48.0Vdc Output; 450W Output
June 7, 2013 ©2012 General Electric Company. All rights reserved. Page 6
Test Configurations
Note: Measure the input reflected-ripple current with a simulated
source inductance (LTEST) of 12 µH. Capacitor CS offsets possible
battery impedance. Measure the current, as shown above.
Figure 7. Input Reflected Ripple Current Test Setup.
Note: Use a C
out
(470 µF Low ESR aluminum or tantalum capacitor
typical), a 0.1 µF ceramic capacitor and a 10 µF ceramic capacitor,
and Scope measurement should be made using a BNC socket.
Position the load between 51 mm and 76 mm (2 in. and 3 in.) from the
module.
Figure 8. Output Ripple and Noise Test Setup.
Note: All measurements are taken at the module terminals. When
socketing, place Kelvin connections at module terminals to avoid
measurement errors due to socket contact resistance.
Figure 9. Output Voltage and Efficiency Test Setup.
Design Considerations
Input Source Impedance
The power module should be connected to a low
ac-impedance source. A highly inductive source
impedance
can affect the stability of the power module. For the test
configuration in Figure 7, a 470μF Low ESR aluminum
capacitor, C
IN
, mounted close to the power module helps
ensure the stability of the unit.
Consult the factory for further application guidelines.
Output Capacitance
The JRCW450U power module requires a minimum output
capacitance of 440µF Low ESR
aluminum capacitor, C
out
to
ensure stable operation over the full range of load and line
conditions, see Figure 8. If the ambient temperature is under -
20C, it is required to use at least 3 pcs of minimum capacitors
in parallel. In general, the process of determining the
acceptable values of output capacitance and ESR is complex
and is load-dependent.
Safety Considerations
For safety-agency approval of the system in which the power
module is used, the power module must be installed in
compliance with the spacing and separation requirements of
the end-use safety agency standard, i.e., UL 60950-1, 2nd Ed.,
CSA No. 60950-1 2 nd Ed., and VDE0805-1 EN60950-1, 2nd Ed.
For end products connected to –48V dc, or –60Vdc nominal
DC MAINS (i.e. central office dc battery plant), no further fault
testing is required. *Note: -60V dc nominal battery plants are
not available in the U.S. or Canada.
For all input voltages, other than DC MAINS, where the input
voltage is less than 60V dc, if the input meets all of the
requirements for SELV, then:
 The output may be considered SELV. Output voltages will
remain within SELV limits even with internally-generated
non-SELV voltages. Single component failure and fault
tests were performed in the power converters.
One pole of the input and one pole of the output are to be
grounded, or both circuits are to be kept floating, to maintain
the output voltage to ground voltage within ELV or SELV limits.
However, SELV will not be maintained if V
I
(+) and V
O
(+) are
grounded simultaneously.
For all input sources, other than DC MAINS, where the input
voltage is between 60 and 75V dc (Classified as TNV-2 in
Europe), the following must be meet, if the converter’s output
is to be evaluated for SELV:
 The input source is to be provided with reinforced
insulation from any hazardous voltage, including the ac
mains.
 One Vi pin and one Vo pin are to be reliably earthed, or
both the input and output pins are to be kept floating.
 Another SELV reliability test is conducted on the whole
system, as required by the safety agencies, on the
combination of supply source and the subject module to
verify that under a single fault, hazardous voltages do
not appear at the module’s output.