Ericsson Internal
E
EZIWSON
PRODUCT SPECIFICATION
3 (4)
Prepared (also subject responsible if other)
No.
1/1301-BMR 451 Uen
3
Technical Specification
Approved
Checked
Date
Rev
Reference
EN/LZT 146 401 R4A May 2015
BMR 451 Digital PoL Regulators
Input 4.5-14 V, Output up to 40 A / 132 W
SEC/D (Julia You)
2011-12-21
G
© Ericsson AB
Isolated DC/DC converters
Safety Specification
It is recommended that a slow blow fuse is to be used at
the input of each DC/DC converter. If an input filter is used
in the circuit the fuse should be placed in front of the input
filter.
In the rare event of a component problem that imposes a
short circuit on the input source, this fuse will provide the
following functions:
General information
Ericsson Power Modules DC/DC converters and DC/DC
regulators are designed in accordance with safety
standards IEC/EN/UL 60950-1 Safety of Information
Technology Equipment.
IEC/EN/UL 60950-1 contains requirements to prevent
injury or damage due to the following hazards:
•
•
Isolate the fault from the input power source so as
not to affect the operation of other parts of the
system.
Protect the distribution wiring from excessive
current and power loss thus preventing hazardous
overheating.
•
•
•
•
•
•
Electrical shock
Energy hazards
Fire
Mechanical and heat hazards
Radiation hazards
Chemical hazards
The galvanic isolation is verified in an electric strength test.
The test voltage (Viso) between input and output is
1500 Vdc or 2250 Vdc (refer to product specification).
On-board DC/DC converters and DC/DC regulators are
defined as component power supplies. As components
they cannot fully comply with the provisions of any safety
requirements without “Conditions of Acceptability”.
Clearance between conductors and between conductive
parts of the component power supply and conductors on
the board in the final product must meet the applicable
safety requirements. Certain conditions of acceptability
apply for component power supplies with limited stand-off
(see Mechanical Information for further information). It is
the responsibility of the installer to ensure that the final
product housing these components complies with the
requirements of all applicable safety standards and
regulations for the final product.
24 V DC systems
The input voltage to the DC/DC converter is SELV (Safety
Extra Low Voltage) and the output remains SELV under
normal and abnormal operating conditions.
48 and 60 V DC systems
If the input voltage to the DC/DC converter is 75 Vdc or
less, then the output remains SELV (Safety Extra Low
Voltage) under normal and abnormal operating conditions.
Single fault testing in the input power supply circuit should
be performed with the DC/DC converter connected to
demonstrate that the input voltage does not exceed
75 Vdc.
Component power supplies for general use should comply
with the requirements in IEC 60950-1, EN 60950-1 and
UL 60950-1 Safety of Information Technology Equipment.
There are other more product related standards, e.g.
IEEE 802.3 CSMA/CD (Ethernet) Access Method, and
ETS-300132-2 Power supply interface at the input to
telecommunications equipment, operated by direct current
(dc), but all of these standards are based on
If the input power source circuit is a DC power system, the
source may be treated as a TNV-2 circuit and testing has
demonstrated compliance with SELV limits in accordance
with IEC/EN/UL60950-1.
Non-isolated DC/DC regulators
IEC/EN/UL 60950-1 with regards to safety.
The input voltage to the DC/DC regulator is SELV (Safety
Extra Low Voltage) and the output remains SELV under
normal and abnormal operating conditions.
Ericsson Power Modules DC/DC converters and DC/DC
regulators are UL 60950-1 recognized and certified in
accordance with EN 60950-1.
The flammability rating for all construction parts of the
products meet requirements for V-0 class material
according to IEC 60695-11-10, Fire hazard testing, test
flames – 50 W horizontal and vertical flame test methods.
The products should be installed in the end-use equipment,
in accordance with the requirements of the ultimate
application. Normally the output of the DC/DC converter is
considered as SELV (Safety Extra Low Voltage) and the
input source must be isolated by minimum Double or
Reinforced Insulation from the primary circuit (AC mains) in
accordance with IEC/EN/UL 60950-1.