Vicor VI-J00 Family DC-DC Converters and Configurable Power Supplies - Manual (Page 49)

Design Guide & Applications Manual
For VI-200 and VI-J00 Family DC-DC Converters and Configurable Power Supplies
VI-200 and VI-J00 Family Design Guide Rev 3.5 vicorpower.com
Page 48 of 98
Apps. Eng. 800 927.9474 800 735.6200
16. Offline Front End
SINGLE PHASE FRONT ENDS
Vicor’s single phase non-isolated AC front ends are
available in both PCB and chassis mount versions, and
deliver reliable DC bus voltage to VI-x6x converter
modules or Mega Modules at power levels up to 250,
500 and 750 W. These front ends are strappable to
provide operation from either 115 Vac or 230 Vac single
phase lines, and provide conducted EMC filtering to VDE /
FCC Level B. They also offer transient surge protection, active inrush limiting, AC-OK (AC fail
indicator), and a BUS-OK status output suitable for
controlling Vicor modules via the GATE IN pin.
Vicor’s front ends have been designed to comply with
the requirements of major safety agencies when used
in conjunction with recommended mains switching
and input fusing.
NOTES:
• Ambient temperature must be less than 50˚C in
free air. Temperature may exceed 50˚C with moving
air. (refer to derating curves in Figure 16–2)
• Do not obstruct vent holes.
• Observe module installation requirements (refer to
Module Do & Don’ts , Section 3).
• Minimize length of all unshielded line cord.
• Minimum conductor size for supply is 16 AWG
(250 W), 14 AWG (500 W) and 12 AWG (750 W)
including the 115/230 strap.
• If the DC output bus is shorted before application
of AC power, the fuse may not blow, and the unit
will not turn on.
• If wire distance from front end to modules is
greater than 3 feet, (0.91 m) install a TRANSZORB
(Part #1.5KE400A) across the input of each module.
• If unit is strapped for 115 V operation and 230 V is
applied, the input fuse will clear. Replace fuse,
strap correctly and reapply power.
• To control EMC most effectively, the return path to
ground from either the front end or modules
should be made via a good RF ground (i.e., a
braided wire) if possible.
• The BUS-OK, Vdc– and Vdc+ lines should be run in
close proximity to one another or as a twisted
group between the front end and modules.
• Bypass the baseplates of the modules to –IN and
–OUT (refer to EMC Considerations , Section 9).
INPUT OUTPUT
Ground all baseplates
to Earth Ground
USE #4 HARDWARE
TORQUED @ 5 in.-lbs.
(4 PLACES)
CONNECT
ST1 TO ST2
FOR 115 Vac
OPEN FOR
230 Vac
EARTH
GROUND
A.C. MAINS
F1
Earth Ground
L1 (Phase)
L2 (Neutral)
ST1
ST2
BUS-OK
VDC–
VDC+
Fn
F2
F3
F4
+V
AC-OK+
AC-OK–
(500 W, 750 W front end only)
Vce sat.
<0.4 V @
1.5 mA <70 V
–IN
GATE IN VI-x6x
Module
+IN
–IN
GATE IN VI-x6x
Module
+IN
–IN
GATE IN VI-x6x
Module
+IN
–IN
GATE IN VI-x6x
Module
+IN
FUSING INFORMATION
FOR SAFE OPERATION, REPLACE ONLY
WITH RECOMMENDED FUSES
250 W — FUSE 1: 6.3 A / 250 V (IEC 5 x 20 mm) BUSSMAN
GDB-6.3 OR 7 A / 250 V (3AG 1/4" x 1 1/4") LITTLEFUSE
314-007 OR BUSSMAN MTH-7 OR ABC-7
FUSES 2,3,4...n: 3 A / 250 V BUSSMAN PC-TRON
500 W — FUSE 1: 12A/250V BUSSMAN ABC-12,
LITTLEFUSE 314-012
FUSES 2,3,4...n: 3 A / 250 V BUSSMAN PC-TRON
750 W — FUSE 1: 15 A / 250 V BUSSMAN ABC-15,
LITTLEFUSE 314-015
FUSES 2,3,4...n: 3 A / 250 V BUSSMAN PC-TRON
Figure 16–1 — 250 W, 500 W, 750 W front ends
NOTE: x,y capacitors not shown for clarity