Vicor PFC MegaPAC-HPEL Power Factor Corrected AC-DC Switchers - Manual (Page 17)

UG:119 vicorpower.com Applications Engineering: 800 927.9474 Page 17
Enable/Disable control of Maxi Module Arrays
When using the Enable/Disable function on an output that consists of two or more Maxi
modules, it is necessary to connect the E/D pins of the corresponding module locations
together such that both modules are commanded to turn ON or OFF simultaneously.
Example:
Slots 2, 4 and 6 have been configured as a single output parallel array (see Fig. 6)
In order to disable the 48V output, E/D 2, E/D 4 and E/D 6 should be shorted together
as shown in Fig. 6. With E/Ds connected together, a single switch can then be used to
remotely enable and disable the output.
**Note: For single output power supply configurations, the simplest method of remotely enabling and
disabling the output is to use the General Shutdown (GSD) function.
General Shutdown /GSD (J10-12)
The GSD control pin on J10-12 allows simultaneous shutdown of all ConverterPAC
outputs (see Connector Pin Identification on Page 16). This pin must be pulled down
to less than 0.7 V, and will sink 13 mA maximum to shut down all outputs. The GSD
pin should be open circuited or allowed to exceed 4.5 V when not in use, or when
the outputs are to be enabled. Do not apply more than 6 V to this input at any time.
Normal open circuit voltage is 1.5 to 3 V with respect to Signal Ground. If driven from
an electromechanical switch or relay, a capacitor should be connected to eliminate the
effects of switch bounce.
AC OK / Power Fail (J10-11)
This is an active high TTL compatible signal and provides a status indication of the AC
input power (see Figure 7 and Connector Pin Identification on Page 16). It is capable of
sourcing 0.5 mA at > 3.2 V and sink 16 mA at < 0.5 V. This signal switches to a TTL “1”
when the high voltage bus exceeds low-line condition during turn-on, and switches to a
TTL “0” 3 ms (minimum) before loss of output regulation due to the loss of input
AC power. This signal can be used to warn external control circuits of an impending
loss of power.
Figure 6.
Enable/Disable Control
of Maxi Arrays
PZL48V/12.5AN
PZL48V/12.5AJS1
PZL48V/12.5AJS1
Slot# 1
Slot# 2
Slot# 3
Slot# 4
Slot# 5
Slot# 6
Slot# 7
Slot# 8
J1
J10
2
4
6
10
12
3
Power Facto
r Corrected
MegaPAC
L5V/40A
L3.3V/40A