Vicor 4kW MegaPAC-EL AC-DC Switchers - Manual (Page 16)

UG:108 vicorpower.com Applications Engineering: 800 927.9474 Page 16
Interface Connections
Chassis Input Power Terminals (J1)
Input AC power is applied to a plug-in connector, J1, that accepts soldered terminals
with a wire size of 12 AWG. For operation on high voltage DC input, input power can be
connected to any two input lines. A fault-clearing device should be installed at the input
of the unit. A user-accessible input fuse is not present within the unit. For an output of
2,000 W - 4,000 W with operation on 208 Vac, 3Æ input, a 20 A fuse in each input line is
acceptable. Input power cables should be shielded to minimize radiated noise effects.
Output Power Connections (+P, -P for Single Output, or J1A/J1B for Dual Outputs)
For single output ConverterPACs, these terminals are two 1/4-20 plated steel studs. The
upper stud is positive with respect to the lower stud. For dual output ConverterPACs,
there is a 6-pin Molex connector for each output. J1A pins 1 and 4 are the +Output,
and J1A pins 2 and 5 are the -Output. Pins 3 and 6 are the Remote Sense terminals. Use
appropriate wire size rated to handle the full output current, including short circuit
levels. Avoid large current loops in output cables; run power and return cables next
to one another to minimize inductive effects. All outputs are isolated and can provide
positive or negative outputs.
Output +/-Sense Connections (P2 for Single Output, or J1A/J1B for Dual Outputs)
Newer power supplies may have some outputs configured with the Autosense feature
that automatically locally senses the output if remote sense is not used. To check if an
output has the Autosense feature, measure the impedance from the + Out to + Sense and
- Out to - Sense pins. If the impedance is 5 ohms, then the output has Autosense and
does not require local sense jumpers.
For units without Autosense, sense connections must be made. When making sense
connections, keep in mind that although all outputs are open-Sense protected, the
+/-Sense terminals MUST be connected to their respective outputs before the 3
Phase MegaPAC - EL and 4kW MegaPAC - EL is powered up. Regardless of the output
polarity configured, the +Sense should always connect to the +Power output. The
-Sense connects to the -Power output. Sense connections are not required on booster
ConverterPACs, BatPACs, or if the Local Sense option is specified. Sense pins can be
accessed either on P2-6/P2-7 or J1A/J1B on dual output units.
Figure 3.
Input Panel Connector
J1-4 Earth Ground
J1-1 Line 3
J1-2 Line 2
J1-3 Line 1
J1
End of Life - Not Recommended for New Designs