GE Industrial Solutions EHHD015A0A Hammerhead Series - Manual (Page 6)

GE Data Sheet
EHHD015A0A Hammerhead™ Series; DC-DC Converter Power Modules
18-75Vdc Input; 5Vdc, 15.0A, 75W Output
April 4, 2013 ©2012 General Electric Company. All rights reserved. Page 6
Test Configurations
TO OSCILLOSCOPE CURRENT PROBE
L
TES T
12μH
B
A
TTE
R
Y
C S 220μF
E.S.R.<0.1 
@ 20°C 100kHz
33-100μF
Vin+
Vin-
NOTE: Measure input reflected ripple current with a simulated
source inductance (L
TEST
) of 12μH. Capacitor C
S
offsets
possible battery impedance. Measure current as shown
above.
Figure 7. Input Reflected Ripple Current Test Setup.
NOTE: All voltage measurements to be taken at the module
terminals, as shown above. If sockets are used then
Kelvin connections are required at the module terminals
to avoid measurement errors due to socket contact
resistance.
V O (+)
V O ( – )
RESISTIVE
LOAD
SCOPE
COPPER STRIP
GROUND PLANE
10uF 1uF
Figure 8. Output Ripple and Noise Test Setup.
Vout+
Vout-
Vin+
Vin-
R LOAD
R
contact
R
distribution
R
contact
R
distribution
R
contact
R
contact
R
distribution
R
distribution
V IN
V
O
NOTE: All voltage measurements to be taken at the module
terminals, as shown above. If sockets are used then
Kelvin connections are required at the module terminals
to avoid measurement errors due to socket contact
resistance.
Figure 9. Output Voltage and Efficiency Test Setup.
 =
V
O
. I
O
V
IN
. I
IN
x 100 % Efficiency
Design Considerations
Input Filtering
The power module should be connected to a low
ac-impedance source. Highly inductive source impedance
can affect the stability of the power module. For the test
configuration in Figure 7 a 33-100μF electrolytic capacitor
(ESR<0.7 at 100kHz), mounted close to the power module
helps ensure the stability of the unit. Consult the factory for
further application guidelines.
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.
UL60950-1, CSA C22.2 No.60950-1, and VDE0805-
1(IEC60950-1).
If the input source is non-SELV (ELV or a hazardous voltage
greater than 60 Vdc and less than or equal to 75Vdc), for the
module’s output to be considered as meeting the
requirements for safety extra-low voltage (SELV), all of the
following must be true:
 The input source is to be provided with reinforced
insulation from any other hazardous voltages, including
the ac mains.
 One V
IN
pin and one V
OUT
pin are to be grounded, or
both the input and output pins are to be kept floating.
 The input pins of the module are not operator
accessible.
 Another SELV reliability test is conducted on the whole
system (combination of supply source and subject
module), as required by the safety agencies, to verify
that under a single fault, hazardous voltages do not
appear at the module’s output.
Note: Do not ground either of the input pins of the module
without grounding one of the output pins. This may
allow a non-SELV voltage to appear between the
output pins and ground.
The power module has extra-low voltage (ELV) outputs when
all inputs are ELV.
All flammable materials used in the manufacturing of these
modules are rated 94V-0, or tested to the UL60950 A.2 for
reduced thickness.
For input voltages exceeding –60 Vdc but less than or equal
to –75 Vdc, these converters have been evaluated to the
applicable requirements of BASIC INSULATION between
secondary DC MAINS DISTRIBUTION input (classified as
TNV-2 in Europe) and unearthed SELV outputs.
The input to these units is to be provided with a maximum 6
A fast-acting fuse in the ungrounded lead.