VICOR PFC MegaPAC-EL, PFC MegaPAC-HPEL User Manual

USER GUIDE | UG:119

PFC MegaPAC-EL

TM

PFC MegaPAC-HPELTM
Power Factor Corrected AC-DC Switchers

Contents Page

Overview 1

Standard Features 2

Optional Features 2

Mechanical Considerations 3

MegaPAC Dos and Don’ts 3

Technical Description 4

Configuring and
Reconfiguring MegaPACs 5

ConverterPAC Functional
Description 7

Part Numbering 8

ConverterPAC Output and
Connector Pin Identification 10

PFC MegaPAC-EL and -HPEL
Quick Install Instructions 11

PFC MegaPAC-EL and PFC
MegaPAC-HPEL
Mechanical Drawing 14

Interface Connections 15

Specifications 22

Output Studs 23

Output Power Derating 24

PFC MegaPAC-EL/HPEL
Connector Kit (19-130040)
Listing 24

Connector Kit for
Dual Outputs only ­MegaPAC Family 19-130042 24

Current Share Boards ­Optional Feature 25

Current Share Boards ­Optional Feature Diagram 27

Output Sequencing 28

Overview

The PFC MegaPAC-EL and PFC MegaPAC High Power Low Noise (HPEL) combine power factor
correction (PFC) with the configurability of the MegaPAC family of power supplies. The
PFC MegaPAC-EL and PFC MegaPAC-HPEL provide up to 1,600W and 2,400W of output power
respectively and have power densities of 4.3W/in3 and 6.5W/in3 respectively. The chassis has eight slots
and can provide as many as 16 outputs. The PFC MegaPAC-EL and PFC MegaPAC-HPEL have the same
input and output connections, mounting points and the same dimensions: 3.4 x 6.0 x 15.6in
[85,6 x 152,4 x 396,2mm]. Note that length of older units were 15.5in [393,6mm].

A complete power supply is configured at the factory by selecting and inserting up to eight (four – six
for the PFC MegaPAC-HPEL depending on ConverterPACs used) same length slide-in output assemblies
called ConverterPACs. ConverterPACs™ incorporate one or two VI-200™ / VI-J00™ and / or Maxi Vicor
DC-DC converters and are available in a wide selection of output voltage and power levels. The net
result is a power supply that offers the advantages of a custom supply, but is assembled from standard
and modular building blocks.

Manufactured at Vicor, the entire family of MegaPAC power supplies is completely user-configurable.
If output requirements change, i.e., more power or a different output voltage is needed, upgrading
is easy: simply unlock a single screw and replace the slide-in ConverterPAC assembly with one that is
of the same length and has the desired voltage power rating. For additional flexibility, ConverterPACs
can be connected in parallel to increase output power (booster ConverterPACs), or in series for
higher voltages (total output voltage should not exceed 400V). The driver is to the left of the
boosters when looking at the output end of the supply. A user-friendly interface provides control and
output sequencing capability (see Page 16 for more information about this capability), in addition to
useful status indicators. Please consult our Applications Engineering Department if you have other
special requirements.

Note: This user guide contains references to parts and products that are no longer available for new designs.
They remain included for reference only.

UG:119 Page 1

Standard Features

 Power Factor Correction; 0.99 at 115VAC, 0.95 at 230V
 Universal Input: 85 – 264VAC, 47 – 500Hz, or 100 – 380V

AC

DC

 Power Outputs:

PFC MegaPAC-EL™: 1,600W at 230VAC PFC MegaPAC-HPEL™: 2,400W at 230VAC
1,200W at 115VAC 1,200W at 115V

AC

 Outputs:

PFC MegaPAC-EL and HPEL: Up to 16 outputs

 Output ripple: 10mV

or 0.15% whichever is greater

P-P

 Fan Cooled
 Full-power to 40°C; half power to 60°C
 Soft start for limiting inrush current
 Conducted EMI meets FCC Class A and EN55022 A specifications

(some configurations meet Class B. Contact factory)

 Harmonic Distortion to EN61000-3-2
 RoHS compliant available
 Output Sequencing and General Shutdown

(General Shutdown refer to Page 17. Output sequencing refer to Page 28.
Consult Applications Engineering for automatic sequencing circuitry.)

 Overcurrent protection on all outputs
 Overvoltage protection on all ConverterPAC outputs

(not applicable with VI-J00 modules)

 Overtemperature limiting on all ConverterPAC outputs

(not applicable with VI-J00 modules)

 Size: 3.4 x 6.0 x 15.6in [85,6 x 152,4 x 396,2mm]
 Safety Agency Approvals: CE Mark, cTÜVus, UL

Optional Features

 DC OK status signal
 Current Share Boards - see Pages 25 – 27
 Output voltage adjustment range with built-in potentiometer

UG:119 Page 2

Mechanical Considerations

The PFC MegaPAC-EL™ and PFC MegaPAC-HPEL™ can be mounted on any of four surfaces using
standard 8-32 or 4mm screws. The chassis comes with four mounting points on each surface; maximum
allowable torque is 20lb.in. The maximum penetration is 0.15in [3.8 mm].

When selecting a mounting location and orientation, the unit should be positioned so air flow is
not restricted. Maintain a 2in minimum clearance at both ends of the PFC MegaPAC-EL and PFC
MegaPAC-HPEL and route all cables so airflow is not obstructed. The standard unit draws air in at the
fan side / AC input side and exhausts air out the load side. If airflow ducting is used, use caution, as
sharp turns could present back pressure to the PFC MegaPAC-EL and PFC MegaPAC-HPEL. The fan
moves approximately 30CFM of air.

Avoid excessive bending of output power cables after they are connected to the PFC MegaPAC-EL
and PFC MegaPAC-HPEL. For high-current outputs, use cable ties to support heavy cables in order to
minimize mechanical stress on output studs. Be careful not to short-out to neighboring output studs.
The PFC MegaPAC-EL and PFC MegaPAC-HPEL units are supplied with serrated, flanged hex-nuts on all
output studs. Therefore, thread-locking compounds or lock washers are not required. The maximum
torque recommended on flanged nuts is 45lb.in. Never loosen the inner nut on a ConverterPAC™. This
nut supports the hardware inside the ConverterPAC and is factory torqued.

Avoid applications in which the unit is exposed to excessive shock or vibration levels. In such
applications, a shock-absorption mounting design is required.

MegaPAC™ Dos and Don’ts

 For units without Autosense, do not leave ConverterPAC Sense lines open. Always terminate them to

their respective output locally or at the load. Use twisted pair 22-24AWG wire. If ConverterPAC has
Autosense, no local-sense connection is required. See Pages 11 and 12 for more information
on Autosense.

 If needed, use Connector Kit # 19-130040 for the PFC MegaPAC-EL and PFC MegaPAC-HPEL.
 Always fill all output slots of the MegaPAC. If a slot is not filled with a ConverterPAC, it should be

filled with an airblock. Airblocks are plastic assemblies whose main function is to fill up an empty slot.
Any airflow escape from an empty slot significantly degrades thermal performance and can result in
overheating and damage to the power supply.

 Always turn the power supply off before disconnecting input or output wires.
 NEVER disconnect the +Out and –Out load wires while the supply is operating, as disconnecting WILL

cause damage to the power supply.

 Do not unplug ConverterPACs while input power is applied. They are not designed for

hot-plug applications.

 Do not restrict airflow to the unit. The cooling fan draws air into the unit and forces it out at the

output power terminals.

UG:119 Page 3

 For power expansion, use booster ConverterPACs™. Viewing the unit from the output terminal side,

always insert boosters to the right side of the driver.

 Do not use boosters as independent outputs. Disconnecting bus bars will damage

booster ConverterPACs.

 For booster arrays, do not remove bus bars.
 Always ensure that output hex-nuts are properly torqued before applying power to supply.
 Run the output (+/–) power cables next to each other to minimize inductance.
 Wait five minutes after shutting off power before inserting or removing ConverterPACs.
 The MegaPACs does not have user serviceable components. They must be returned to the factory

for repairs. Contact Customer Service for a RMA number before returning the unit. Do not attempt
to repair or modify the power supply in any manner other than the exchange of ConverterPACs as
described in this Design Guide.

 Insert proper fault protection at power supply input terminals (i.e., a fuse).
 Use proper size wires to avoid overheating and excessive voltage drop.
 Never loosen the inner nut on a ConverterPAC.
 Verify output nuts are tight before powering up.
 FinQPACs™ require two slots each because of the larger heat sink attached to dissipate the extra

heat generated by the higher-power Maxi module. Refer to Page 8 for more information on which
ConverterPACs can be used.

Technical Description

The PFC MegaPAC-EL™ and PFC MegaPAC-HPEL™ chassis consists of an offline single phase,
power-factor-corrected front end, EMI filter, cooling fan, low-noise filters, customer interface and
associated housekeeping circuits. Input AC mains voltage (L1, L2 and GND) is applied to a terminal
block. The input current is passed through an EMI filter designed to meet conducted noise limit A
specifications of FCC Part 15, VDE 0871 and EN55022 Class A. At start up, inrush current is limited by a
PTC thermistor. The PTC is shunted out shortly after initial power up by a DC bus voltage Sense circuit
driving a relay. After rectification, the input voltage is put through a boost converter that keeps the AC
input current sinusoidal and synchronized with the AC input voltage (in compliance with EN61000).
The boost converter delivers regulated high voltage DC to the hold-up capacitors and backplane.
The backplane supplies power to a variety of ConverterPAC assemblies that provide the desired
regulated outputs.

Voltage conversion in the output assemblies is achieved by the Vicor family of Zero-Current Switching
(ZCS) DC-DC converters. These are forward converters in which the main switching element switches
at zero current. This patented topology has a number of unique attributes: low-switching losses;
high-frequency operation resulting in reduced size for magnetics and capacitors; excellent line- and
load- regulation; wide-adjustment range for output; low EMI / RFI emissions and high efficiencies.

At initial power up, the PFC MegaPAC-EL and PFC MegaPAC-HPEL outputs are disabled to limit the
inrush current and to allow the DC bus potential to settle out to the correct operating level.
A low-power flyback converter operating with PWM current-mode control converts the high-voltage
DC bus into regulated low voltage to power the internal housekeeping circuits and DC cooling fan. The
internal housekeeping VCC comes up within two seconds after the application of input power. Once the
high-voltage bus is within its limits, the AC OK signal asserts to a TTL “1” indicating the input power is
OK and enables the power outputs. An auxiliary VCC output of 5VDC sourcing up to 0.3A is provided for
peripheral use.

UG:119 Page 4

An output Enable / Disable function is provided by using an optocoupler to control the Gate In pins
of the ConverterPAC™ assemblies. If the Enable / Disable control pin is pulled low, the optocoupler
turns on, pulling the Gate In pin low and disabling the ConverterPAC output. The nominal delay for an
output to come up when measured from release of the Enable / Disable pin is 10 – 15ms. The General
Shutdown function controls all outputs simultaneously and works in a similar manner.

The ride-through (hold-up) time is the amount of time the load can be supported before loss of output
regulation after the loss of input power. Detecting the loss of input power takes a finite time period
after which the AC Power OK signal goes from a TTL “1” to “0." This signal is available for use within

1.2s after initial power up and can be used to indicate an impending loss of power. At least 3ms of
warning time is given. Following the loss of input power, the outputs are disabled when the bus voltage
drops below its operating threshold.

Figure 1

PFC MegaPAC-EL™ and

PFC MegaPAC-HPEL™

low-noise architecture

Input

Line Filter

Customer

Current

Sample

Interface

Rectifier

Fan

Waveform

Sample

Current
Monitor

Soft Start

Circuit

PFC Control

E/D Control

Boost Converter

Enable/Disable Control

Housekeeping

Power

High Voltage
DC Bus

QPAC #1

QPAC #2

QPAC #3

QPAC #8

Power
Output

Power
Output

Power
Output

Power
Output

Configuring and Reconfiguring MegaPACs

Most ConverterPACs of the same length can be inserted into any available slot of a MegaPAC chassis.
They can also be easily added, replaced or moved by sliding the assemblies in or out of a MegaPAC
chassis. For outputs greater than 200W, a driver QPAC™ and one or more booster ConverterPACs will
be used. For outputs greater than 600W, a driver FinQPAC™ and one or more booster ConverterPACs
will be used. Arrays of drivers and boosters should be configured so all boosters are placed in the slots
to the immediate right of the driver when looking at the output end of the MegaPAC.

Prior to removing or installing ConverterPACs, you must remove power from the MegaPAC
and wait five minutes. Failure to do so can result in personal injury or damage to the supply.

Take standard ESD precautions when handling ConverterPACs.

Removing ConverterPACs

ConverterPACs can be removed by loosening the captive screw at the base. Once this screw has been
loosened, the ConverterPAC will slide out of the chassis. Once a ConverterPAC has been removed,
the empty slot MUST be filled with either another ConverterPAC or an airblock. If the slot is left
empty, it will provide an airflow escape and cause failure to the power supply.

UG:119 Page 5

Figure 2

Paralleling ConverterPACs

Installing ConverterPACs as Drivers

ConverterPACs™ can be installed in empty slots by simply sliding in the new ConverterPAC and securing
the screw at the base. Torque the retaining screw to 0.23N.m (2lb.in); do not overtighten. Power and
interface connections can be made after the ConverterPAC has been installed.

Installing Booster ConverterPACs to Increase Output Power

ConverterPACs can be paralleled for more power. Additional power to an output is obtained by
connecting one or more boosters in parallel with a single driver. The driver can be placed in any open
slot. All boosters should be inserted in the slots to the immediate right of the driver as viewed from
the output end of the MegaPAC™. Figure 2 shows a driver placed in slots #1 and 3, boosters placed
in slots #2 – 4. After inserting the driver and boosters, they are paralleled using bus bars across the
positive- and negative-output studs. Drivers should not be paralleled with each other. Bus bars between
a driver and booster(s) should never be disconnected. For help in identifying boosters and drivers, refer
to the Part Numbering section on Page 8. Please note that total output voltage should not exceed the
converter baseplate-output isolation rating of 400V. For a detailed guideline on how outputs should be
placed in series, please refer to: AN:204 Creating High-Voltge Outputs.

Bus Bars for Paralleling

Loosen screw to

remove ConverterPAC

12

Driver

Boosters

4

3

5

6

8

7

UG:119 Page 6

+

_

VI-J00

M1

M2

+

_

M2

VI-200

VI-J00

M1

QPAC

DualPAC

ConverterPAC Functional Description

ConverterPACs™ are the family of slide-in output assemblies used in MegaPAC™ power supplies.
Most ConverterPACs of the same length are interchangeable within a MegaPAC or between different
AC input MegaPAC chassis. They can be added, moved or changed as necessary. A key feature of

the Extended Length ConverterPAC is the low ripple and noise output to 10mV
whichever is greater. The following Extended-Length ConverterPACs can be used in the

PFC MegaPAC/EL - Low Noise.

QPAC™ (L)

The QPAC output assembly consists of a VI-200™ DC-DC converter that converts the unregulated
high-voltage bus to the desired regulated output voltage. Each QPAC (L) can provide up to 200W of
output power, and booster QPACs can be added in parallel for more power. Power and slave QPACs
can be added in parallel for more power. QPACs are fused with a PC-Tron, DC-rated, fast-acting fuse.
An active preload ensures the DC-DC converter operates in its highest-noise performance range.
As the load on the module increases, the preload removes itself from the circuit. QPACs, using the
VI-200 module, have an optional DC OK TTL signal. All QPACs have overcurrent protection with
automatic recovery when the overcurrent condition is removed. Overvoltage Protection (OVP) and
Overtemperature Limiting (OTL) are available. Please note that for the QPAC (L), the output voltage

from either output terminal to chassis should not exceed 400VDC, or peak.

DualQPAC™ (LD)

The DualQPAC output assembly consists of two VI-J00 DC-DC converters that provide two isolated
output voltages. DualQPACs can provide up to 100W of output power from each output. The
DualQPACs are fused with a PC-Tron, DC-rated, fast-acting fuse. An active preload ensures the DC-DC
converter operates in its highest noise performance range. OVP and OTL is not available. Please note

that for the QPAC (L) the output voltage from either output terminal to chassis should not
exceed 400VDC, or peak. For detailed pinout description, refer to Page 10.

or 0.15%,

P-P

VI-J00

Maxi

JuniorQPAC

FinQPAC

JuniorQPAC™ (LJ)

The JuniorQPAC output assembly consists of a VI-J00 Vicor DC-DC converter that converts the
unregulated high-voltage bus to the desired regulated output voltage. OVP and OTL is not available.

Please note that for the QPAC (L) the output voltage from either output terminal to chassis
should not exceed 400VDC, or peak.

FinQPAC™ (PZL)

The FinQPAC output assembly consists of a Maxi DC-DC converter that converts the unregulated
high-voltage bus to the desired regulated output voltage. Each Maxi module can provide up to 600W
of output power. Each FinQPAC occupies two slots because it has an extra large heat sink attached
to dissipate the heat generated by this more powerful Maxi converter. It cannot be used in any other
member of the MegaPAC Family. FinQPACs have overcurrent protection with automatic recovery when
the overcurrent condition is removed. Overvoltage Protection (OVP) and Overtemperature Limiting (OTL)
are available. Please note that for the FinQPAC (PZL) the output voltage from either output

terminal to chassis should not exceed 400VDC, or peak.

UG:119 Page 7

List of ConverterPACs™ used in the PFC MegaPAC-EL™ and

PFC MegaPAC-HPEL™ Low Noise and their features

ConverterPAC OVP OCP OTL RS/A S* LS/AS* PG TrimPot

QPAC (L) Std Std Std AS

DualQPAC (LD) N/A Std N/A AS

JuniorQPAC(LJ) N/A Std N/A AS

FinQPAC(PZL)+ Std Std Std AS

[a]

AS

[a]

[a]

[a]

AS

AS

AS

[a]

[a]

[a]

[a]

Opt Opt

Opt N/A

Opt Opt

Opt Opt

OVP Overvoltage Protection (latching) RS Remote Sense

OCP Overcurrent Protection (auto-recovery) LS Local Sense

OTL Overtemperature Limiting AS Autosense

PG Power Good (DC OK TTL Signal) + Maxi OTL is non-latching

[a]

See Pages 11 and 12 for more information on Autosense.

Note: All ConverterPACs mentioned above can be paralleled EXCEPT the DualQPAC and JuniorQPAC.

Part Numbering

PFC MegaPAC-EL MPxA-7xBxxxx-xC-x

D

eg. MP5-782560-G-EL

PFC MegaPAC-HPEL MXxA-7xBxxxx-xC-x

D

eg. MX4-742543-2-EL

MP = MegaPAC™ prefix

xA = number of outputs

7 = power factor corrected

xC = optional code ex. G = RoHS

MX = PFC MegaPAC-HPEL prefix

X = PFC chassis that can use Maxi

xB = Number of modules

xxxx = assigned by Vicor

xD = optional code e.g., EL = Extended Length

ConverterPAC XxDV/xEAx

F

eg. L15V/10A

X = ConverterPAC type (For RoHS, add G to current prefix)

xD = Voltage out

xE = Current out (rounded to one decimal point)

xF = Can be multiple options (see Page 9)

UG:119 Page 8

ConverterPAC™ options

B

Booster module

D

DC OK or Power Good

F

Full 50 – 110% output adjustment

[b]

M

Military Grade module

R

RAM external

[c]

S

Trimpot removed for external

[d]

BatPAC™ adjustment

OUT

[e]

OUT

≤ 15V

OUT

F1

50 – 107.5% output adjustment

F2

50 – 105% output adjustment

F3

50 – 102.5% output adjustment

F4

50 – 100% output adjustment

F5

60 – 110% output adjustment

F6

70 – 110% output adjustment

F7

80 – 110% output adjustment

F8

90 – 110% output adjustment

F9

100 – 110% output adjustment

I

Industrial Grade module

K

Custom SRF module used

P

Preload

[b]

D option: Optional for all ConverterPACs used in this power supply.

[c]

T & F options: Optional for all ConverterPACs used in this power supply EXCEPT the DualQPAC™.

[d]

R option: N/A to any ConverterPACs used in the PFC MegaPAC-EL™ / PFC MegaPAC-HPEL™.

[e]

V options: N/A to any ConverterPACs used in the PFC MegaPAC-EL / PFC MegaPAC-HPEL.

T

90 – 110% output adjustment

T1

90 – 107.5% output adjustment

T2

90 – 105% output adjustment

T3

90 – 102.5% output adjustment

T4

90 – 100% output adjustment

T5

98 – 105% output adjustment

T6

100 – 110% output adjustment

V1

"VXI" low noise (150mV) 15V < V

V2

"VXI" low noise (50mV) V

V3

“VXI” low noise (1% ripple) V

≤ 24V outputs

DC

> 24V

[e]

UG:119 Page 9

ConverterPAC™ Output and Connector Pin Identification

QPAC VI-200 MODULE

DUAL QPAC

(M2)

FinQPAC

QPAC™

JuniorQPAC™

DualQPAC™

+VOUT

OUTPUT ADJUST

–VOUT

J2-PIN1

J2 REMOTE SENSE TRIM/SC & POWER GOOD

MATING HDWR:

HOUSING- MOLEX P/N: 39-01-0073

TERMINALS- MOLEX P/N: 39-00-0031

CRIMP TOOL MOLEX P/N: 57005-5000

+SENSE

7

6

–SENSE

5

TRIM

4

VCC IN

3

POWER GOOD

2

POWER GOOD INVERTED

1

SIGNAL GROUND

J1-B-PIN1(M1)

J1-B

J2-PIN1

TRIM TOP

7

TRIM BOT

6

N/C

5

4

VCC IN

3

POWER GOOD

2

POWER GOOD INVERTED

1

SIGNAL GROUND

J1-A-PIN1

(OUTPUT CONNECTORS)

1 AND 4 +VOUT

1

4

2 AND 5 –VOUT

2

5

6

3

3 +R/SENSE 6 –R/SENSE

J1-A

(OUTPUT CONNECTORS)

1 AND 4 +VOUT

4

1

2 AND 5 –VOUT

5

2

6

3

3 +R/SENSE 6 –R/SENSE

DUALQPAC - COMPONENT SIDE VIEW

MATING HDWR:

HOUSING- MOLEX P/N: 39-01-2060

TERMINALS- MOLEX P/N: 39-00-0039

CRIMP TOOL MOLEX P/N: 11-01-0197

MATING HDWR:

HOUSING- MOLEX P/N: 39-01-2060

TERMINALS- MOLEX P/N: 39-00-0039

CRIMP TOOL MOLEX P/N: 11-01-0197

FinQPAC™

M2

Output A
48V/2.1A

M1

Output B
12V/8.3A

Example: LD12V/8.3A-48V/2.1A

+OUT

OUTPUT ADJUST

–OUT

P2-PIN1

Notes:

1. All ConverterPACs except the FinPAC™ occupy one slot. The FinPAC occupies two slots.

2. New output studs were installed on the ConverterPACs and are 1/8th inch longer.

Refer to Pages 14 and 23 for more information.

P2 REMOTE SENSE TRIM/SC & POWER GOOD

+SENSE

7

6

–SENSE

5

TRIM

4

VCC IN

3

POWER GOOD

2

POWER GOOD INVERTED

1

SIGNAL GROUND

MATING HDWR:

HOUSING- MOLEX P/N: 39-01-0073

TERMINALS- MOLEX P/N: 39-00-0031

CRIMP TOOL MOLEX P/N: 57005-5000

(J1-B)

(J1-A)

J1-B (M1)

J1-A (M2)

UG:119 Page 10