Vicor Westcor PFC Mini Power Factor Corrected AC-DC Switcher - Manual (Page 14)

UG:115 vicorpower.com Applications Engineering: 800 927.9474 Page 14
+Sense/ –Sense (SxJ2/SxJ1)
Current PFC Mini units are shipped with Autosense installed. If the unit does not have
Autosense, sense selection is very important. In units without Autosense, the Sense
lines for the outputs are shipped from the factory with Local Sense installed. If Remote
Sense is desired the Local Sense jumpers can be removed for individual outputs. If the
Local Sense jumpers are removed, the Sense lines must be connected for Remote Sense.
Leaving the Sense lines open will prevent proper output regulation and can result
in damage to the unit.
When Local Sense is used, the power supply will regulate the output at the output
terminals. The voltage appearing at the load may drop slightly due to voltage drop in the
power cables. If it is necessary to compensate for voltage drop along the output power
cables, the output can be trimmed up or configured for Remote Sense. Use stranded
twisted pair 20-22 AWG wire for the Remote Sense lines. Remote Sense can compensate
for a voltage drop of up to 0.5 V, or 0.25 V on each leg.
Installing Remote Sense requires the Local Sense jumpers to be removed. On single
output cards, the Local Sense jumpers are located behind the Sense connector on MBJ1
and J3. To remove the jumpers, make certain the power to the supply is off, and pull
them off the connectors MBJ1 and J3. On dual output cards, the local Sense jumpers
are on either side of the output connector at MBJ1 and J3. The jumpers at MBJ1 are for
output #1, and the jumpers at J3 are for output #2.
The Sense connector for a single output board is a 3-pin connector providing the +Sense
connection on SxJ2-2 and the -Sense connection on SxJ2-3. The Sense connector for
a dual output board is an 18-pin connector that also provides the output and trim
connections. +Sense and -Sense for the first output are located on SxJ1-4 and SxJ1-5,
respectively. +Sense and -Sense for the second output are located on SxJ1-13
and SxJ1-15, respectively.
Figure 5.
Removing Local Sense Jumpers
Local Sense jumpers
located behind
the Sense Connector.
Single Output Sense Connections
Remove jumpers for
Remote Sense on
Output # 1
Remove jumpers for
Remote Sense on
Output # 2
Connector SxJ1
Dual Output Sense Connections
1 7
8 14
2 3 4 5 6
9 10 11 12 13
14 Pin Dual Output Sense Connectors
Local Sense
jumpers are to
the left of the output
connector for
Output # 2 .
Local Sense
jumpers are to
the left of the
output connector for
Output # 1
1
10
9
18
2 3 4 5 6 7 8
11 12 13 14 15 16 17
18 Pin Dual Output Connectors
Local Sense
jumpers are to
the left of the
output connector
for Output # 2 Local Sense
jumpers are to
the left of the
output connector
for Output # 1
Local Sense jumpers
located behind
the Sense Connector.
Single Output Sense Connections
TOP VIEW
END VIEW