Kbvw006a0b series sixteenth-brick power modules, Data sheet, Thermal considerations – GE Industrial Solutions KBVW006A0B Series User Manual
Page 8
GE
Data Sheet
KBVW006A0B Series Sixteenth-Brick Power Modules
36–75Vdc Input; 12.0Vdc Output; 6A Output Current
July 9, 2013
©2012 General Electric Company. All rights reserved.
Page 8
Pre-Bias Startup
The module starts up monotonically into pre-biased load
from 0.0Vdc up to V
out
- 0.6Vdc.
Output Reverse Current with Pre-Bias Output
Voltage
The module does not sink appreciable current (current
flow into the module) that can compromise the reliability
of the product. This condition is valid for either during
startup or shutdown over the output pre-bias voltage
range of 0.0Vdc up to V
out
-0.6Vdc. The test conditions for
startup or shutdown are applicable for application and
removal of input voltage, V
in
or by enabling and disabling
the module via remote On/Off.
Output Voltage Programming
Trimming allows the output voltage set point to be
increased or decreased, this is accomplished by
connecting an external resistor between the TRIM pin
and either the V
O
(+) pin or the V
O
(-) pin.
V
O
(+)
V
O
TRIM
V
O
(-)
R
trim-down
LOAD
V
IN
(+)
ON/OFF
V
IN
(-)
R
trim-up
Figure 12. Circuit Configuration to Trim Output
Voltage.
Connecting an external resistor (R
trim-down
) between the
TRIM pin and the V
O
(-) (or Sense(-)) pin decreases the
output voltage set point. To maintain set point accuracy,
the trim resistor tolerance should be ±1.0%.
The following equation determines the required external
resistor value to obtain a percentage output voltage
change of ∆%
22
.
10
%
511
down
trim
R
Where
100
%
,
,
set
o
desired
set
o
V
V
V
For example, to trim-down the output voltage of the
module by 8% to 11.04V, Rtrim-down is calculated as
follows:
8
%
22
.
10
8
511
down
trim
R
655
.
53
down
trim
R
Connecting an external resistor (R
trim-up
) between the
TRIM pin and the V
O
(+) (or Sense (+)) pin increases the
output voltage set point. The following equation
determines the required external resistor value to obtain
a percentage output voltage change of ∆%:
22
.
10
%
511
%
225
.
1
%)
100
(
11
.
5
, set
o
up
trim
V
R
Where
100
%
,
,
set
o
set
o
desired
V
V
V
For example, to trim-up the output voltage of the module
by 5% to 12.6V, R
trim-up
is calculated is as follows:
5
%
22
.
10
5
511
5
225
.
1
)
5
100
(
0
.
12
11
.
5
up
trim
R
8
.
938
up
trim
R
The voltage between the V
O
(+) and V
O
(–) terminals must
not exceed the minimum output overvoltage protection
value shown in the Feature Specifications table. This limit
includes any increase in voltage due to remote-sense
compensation and output voltage set-point adjustment
trim.
Although the output voltage can be increased by both
the remote sense and by the trim, the maximum
increase for the output voltage is not the sum of both.
The maximum increase is the larger of either the remote
sense or the trim. The amount of power delivered by the
module is defined as the voltage at the output terminals
multiplied by the output current. When using remote
sense and trim, the output voltage of the module can be
increased, which at the same output current would
increase the power output of the module. Care should be
taken to ensure that the maximum output power of the
module remains at or below the maximum rated power
(Maximum rated power = V
O,set
x I
O,max
).
Thermal Considerations
The power modules operate in a variety of thermal
environments; however, sufficient cooling should be
provided to help ensure reliable operation.
Considerations include ambient temperature, airflow,
module power dissipation, and the need for increased
reliability. A reduction in the operating temperature of
the module will result in an increase in reliability. The
thermal data presented here is based on physical
measurements taken in a wind tunnel.
The thermal reference point, T
ref
,
used in the
specifications for open frame modules is shown in Figure
13. For reliable operation this temperature should not
exceed 125
o
C.