Vicor VI-J00 Family DC-DC Converters and Configurable Power Supplies - Manual (Page 59)

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 58 of 98
Apps. Eng. 800 927.9474 800 735.6200
19. AC Input Power System (PFC FlatPAC)
OVERVIEW - PFC FLATPAC
The PFC FlatPAC consists of a universal input (85-264 Vac)
AC front end and one Maxi DC-DC converter in an
integrated mechanical assembly providing up to 575 W of
power. Using Vicor’s Harmonic Attenuator Module (HAM)
and integrated filtering, the PFC FlatPAC meets
EN61000-3-2 harmonic current limits and 0.99 power
factor. The internal filtering provides compliance to
EN55022-A conducted EMI.
The PFC FlatPAC will accept an input voltage of 85-264 Vac,
derate power at 9 W/Vrms as shown in Figure 19–1.
CIRCUIT OPERATION
AC line voltage is applied via an agency-approved terminal
block providing AC mains (L1, L2/N and GND). Current in
the L1 lead is applied to a 15 A / 250 V internal fuse This
current is interrupted only in the event of a catastrophic
failure of a main power component internal to the PFC
FlatPAC.
The input current beyond the fuse is passed through an
EMC filter designed to meet conducted noise limits of
FCC Part 15 EN55022 Class A. At start-up, AC inrush
current is limited by the HAM’s internal circuitry prior to
being passed to the main energy storage capacitors.
The DC-DC converter is held off until the internal DC bus
potential has settled to full operating level. The converter
is then enabled.
Fusing. The PFC FlatPAC’s internal fuse is not
user-replaceable.
Grounding. To satisfy IEC950 Class I grounding
requirements, connect a ground lead to the terminal
marked (GND). Use 2.5 mm
2 / #14 AWG wire.
Input Voltage Connections. Connect the line voltage to
L1 (hot) and L2N (neutral). Use #14AWG input wire.
Recommended connector screw torque is 5 to 7 in-lbs
(0.5 to 0.8 N-m). Recommended strip length is 8 mm.
Refer to Figure 19–2.
Output Wire Gauge. Use the output wire gauge that
corresponds to the output current of your FlatPAC unit,
below: Do not loosen bottom nut. Long cable runs, or
wires in large bundles will require heavier cable to avoid
excessive voltage drops or overheating.
Output Voltage Trimming. The Maxi converters used in
the PFC FlatPAC have a wide trim range of +10% to -
90%. See the Maxi, Mini, Micro design guide for details.
Operating Temperature. Do not allow the PFC FlatPAC
to exceed its maximum operating temperature, which is
reached when the heat sink is 85°C. (Full power can be
delivered up to this temperature.) Heat sink temperature is
a function of the output power and voltage of the supply,
ambient temperature, and airflow across the heat sink.
Always use worst-case conditions when calculating
operating temperature.
AC Mains
Earth Ground
L1
L2/N
GND
Figure 19–2 — AC mains connections
NOTE: Product is internally fused.
+Out
+Sense
Trim
–Sense
–Out
+ V
OUT
V
OUT
RTN
R2
R1
10K
NOTE: +Sense and –Sense must be connected locally or
remotely (shown). See calculator for output voltage trimming
at vicorpower.com
Figure 19–3 — Output sense and trim
Vin (Vrms)
P
o
u
t
(W
)
340
360
380
400
420
440
460
480
500
520
540
560
580
600
85 105 125 145 165 185 205 225 245 265
Figure 19–1 — PFC FlatPAC output power vs. input voltage
100 A–160 A : #2 AWG 30 A–50 A : #8 AWG 10 A–15 A : #14 AWG
75 A–100 A : #4 AWG 20 A–30 A : #10 AWG 6 A–10 A : #16 AWG
50 A–75 A : #6 AWG 15 A–20 A : #12 AWG 0 A–6 A : #18 AWG
Table 19–1