Datasheet

DS_V48SR3R320_12072012
6
Safety Considerations
The power module must be installed in compliance with
the spacing and separation requirements of the
end-user’s safety agency standard, i.e., UL60950,
CAN/CSA-C22.2 No. 60950-00 and EN60950: 2000 and
IEC60950-1999, if the system in which the power
module is to be used must meet safety agency
requirements.
Basic insulation based on 75 Vdc input is provided
between the input and output of the module for the
purpose of applying insulation requirements when the
input to this DC-to-DC converter is identified as TNV-2
or SELV. An additional evaluation is needed if the
source is other than TNV-2 or SELV.
When the input source is SELV circuit, the power module
meets SELV (safety extra-low voltage) requirements. If
the input source is a hazardous voltage which is greater
than 60 Vdc and less than or equal to 75 Vdc, for the
module’s output to meet SELV requirements, all of the
following must be met:
 The input source must be insulated from the ac
mains by reinforced or double insulation.
 The input terminals of the module are not operator
accessible.
 If the metal baseplate is grounded, one Vi pin and
one Vo pin shall also be grounded.
 A SELV reliability test is conducted on the system
where the module is used, in combination with the
module, to ensure that under a single fault,
hazardous voltage does not appear at the module’s
output.
When installed into a Class II equipment (without
grounding), spacing consideration should be given to
the end-use installation, as the spacing between the
module and mounting surface have not been evaluated.
The power module has extra-low voltage (ELV) outputs
when all inputs are ELV.
This power module is not internally fused. To achieve
optimum safety and system protection, an input line fuse
is highly recommended. The safety agencies require a
normal-blow fuse with 5A maximum rating to be installed
in the ungrounded lead. A lower rated fuse can be used
based on the maximum inrush transient energy and
maximum input current.
DESIGN CONSIDERATIONS
Input Source Impedance
The impedance of the input source connecting to the
DC/DC power modules will interact with the modules and
affect the stability. A low ac-impedance input source is
recommended. If the source inductance is more than a
few µH, we advise adding a 10 to 100 µF electrolytic
capacitor (ESR < 0.7 Ω at 100 kHz) mounted close to the
input of the module to improve the stability.
Layout and EMC Considerations
Delta’s DC/DC power modules are designed to operate in
a wide variety of systems and applications. For design
assistance with EMC compliance and related PWB layout
issues, please contact Delta’s technical support team. An
external input filter module is available for easier EMC
compliance design. Application notes to assist
designers in addressing these issues are pending
release. EMC test method and result please see figure
16, figure17 and figure 18.
CX1=CX2=CX3=2.2uF/100V; Ceramic
CX4=100uF/100V；Aluminum Electrolytic
CY1=CY2=4.7nF； L1=1.32mH/3.3A; PULSE P0420.
Fig16: EMC test SCHEMATIC & COMPONENT
SDC ADP Team
SGL
dBµV dBµV
150 kHz 30 MHz
TDF
RBW 9 kHz
PREAMP OFFAtt 10 dB
2 AV
CLRWR
MT 100 ms22.Apr 09 22:23
1 MHz 10 MHz
0
10
20
30
40
50
60
70
80
1
Marker 1 [T2 ]
42.17 dBµV
29.620000000 MHz
55022AV
55022QP
Date: 22.APR.2009 22:23:07
Fig17: EMI test result Vin = 48V Iout=20A AVERAGE
SDC ADP Team
SGL
dBµV dBµV
150 kHz 30 MHz
TDF
1 PK
CLRWR
22.
A
p
r
09 22:2 2
RBW 9 kHz
PREAMP OFFAtt 10 d B
M
T 100
m
s
1
M
H
z 10
M
H
z
0
10
20
30
40
50
60
70
80
55022A V
55022
Q
P
Date: 22.APR.2009 22:22:26
Fig18: EMI test result Vin = 48V Iout=20A Q.PEAK