VHK200W-Q48-S28 CUI Inc, VHK200W-Q48-S28 Datasheet - Page 6

• Manufacturer Part Number: VHK200W-Q48-S28
• Description: CONVERTER DC-DC 28V 7.14A 200W
• Manufacturer: CUI Inc
• Series: V-Infinity VHK200Wr
• Type: Isolatedr

Specifications of VHK200W-Q48-S28

• Output: 28V
• Number Of Outputs: 1
• Power (watts): 200W
• Mounting Type: Chassis Mount
• Voltage - Input: 18 ~ 75V
• Package / Case: Module
• 1st Output: 28 VDC @ 7.14A
• Size / Dimension: 4.23" L x 4.01" W x 1.50" H (107.4mm x 101.9mm x 38.1mm)
• Power (watts) - Rated: 200W
• Operating Temperature: -40°C ~ 100°C
• Efficiency: 87%
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• 3rd Output: -
• 2nd Output: -
• 4th Output: -
• Other names: 102-2025

PART NUMBER: VHK200W
4. INPUT CURRENT
The input voltage source must be able to provide enough current to the converter, otherwise it may not start up or operate properly. A
typical symptom is not starting or unusually low output voltage. In general, it is recommended to be able to provide at least:
Ipeak = 150%*Pout/(η η *Vmin) where Pout is the maximum output power, Vmin is the minimum input voltage and η is the converter's
efficiency. As an example, for VHK200W-Q24-S12 to operate with 10~36V input, 200W output and an efficiency of 86%, the minimum
source current is recommended to be: Ipeak = 150% * 200 / (86% * 10) = 34.88A.
5. INPUT FUSE
To limit the input current and to facilitate input reversal protection and input OVP protection, a fast-acting input fuse is recommended
for the input line. The fuse rating will depend on the input range and should allow for the maximum current at the lowest input volt-
age, as shown in this equation: Ipeak = 150%*Pout/(η η *Vmin).
In the previous example of VHK200W-Q24-S12, the peak input current at 10V was calculated to be 34.88A. A 35A or a 40A fuse may
be suitable for this application. Make sure the fuse voltage rating is higher than the maximum input voltage.
6. INPUT OVP
It is important to ensure the input voltage does not exceed the maximum rated input voltage for that model. To suppress voltage tran-
sients of short durations, the converter includes a transient voltage suppression device (TVS) at the input. The built-in TVS has a
rated breakdown voltage of 39V for the VHK200W-Q24-XX models and 82V for the VHK200W-Q48 models. With small transients of
short-durations, the TVS will limit the input voltage without interrupting the converters operations. For large transients, the TVS may
conduct a large amount of current that may trip the input fuse. Without the input fuse, the converter may suffer permanent damages.
When the fuse is open, replace it with one of same type and ratings.
7. INPUT REVERSAL PROTECTION
If the input voltage is reversed for any reason, the built-in protection circuits in the converter will limit the reverse voltage to one diode
drop which is no more than 1V. With an external input fuse connected, the fuse will open and thus remove power from the converter.
Check the wiring and make corrections as needed. The input fuse will need to be replaced. Make sure the new fuse is of the same
type and rating. Without the input fuse, the converter may suffer permanent damages.
8. REMOTE SENSE
The converter provides regulated outputs at the output terminals. When there is a large current and/or the output cable is of some
length, the voltage at the end of the output cable may be noticeably lower than at the terminals. The converter can compensate up to
0.5V of voltage drop through remote sense terminals. To ensure accurate regulation, run two separate wires (twisted) from the
desired regulation points to the remote sense terminals, as shown below. Even if the load current is low, still connect +Vo to +S and
-Vo to -S.
20050 SW 112
th
Ave. Tualatin, Oregon 97062
Trim
+Vo
-Vo
+S
-S
phone
phone [phone] fax
FIGURE 2. REMOTE SENSE
DESCRIPTION: chassis mount dc-dc converter
fax [phone]
(+)
(-)
Load
www.v-infinity.com
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date
08/2009
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