Output Power Connections
The output power terminals available on the Javelin are 5/16–18
studs with flanged nuts. The positive polarity of the output is the
left stud when viewed from the output end. In order to minimize
parasitic cable inductance and reduce EMI, the output power cables
should be routed in close proximity to one another, and large current
loops should be avoided. To avoid excessive voltage drop, do not
undersize power cables, especially for high current outputs. Exces-
sive cable inductance, coupled with large capacitive loading, can
introduce instability in switching power supplies
.
This problem can
be avoided with proper system design. Consult Mission Power So-
lutions’ Engineering Department for assistance with applications
that use long cable lengths and excessive load capacitance.
Signal Return (J2-4)
Signal Return on J2-4 is an isolated secondary ground reference for all J2 interfacing signals. This is
not
the
same as Earth Ground on input power connector J1.
Inhibit/Enable (J2-7 to J2-8)
The Inhibit/Enable control pins allow the output to be controlled with either “inhibit” or “enable” logic. Con-
necting Inhibit (J2-8) and Enable (J2-7) to ground causes the Javelin to operate. With Inhibit (J2-8) open the
Javelin will operate, and the Enable pin has no effect. Connecting Inhibit to ground and leaving Enable open
will disable the output of the Javelin. Refer to Table 2 (Pg. 2).
AC OK (J2-6)
AC OK is an active high TTL-compatible signal and provides a status indication of the AC input power. It is
on pin J2-6 and is capable of sinking 16 mA maximum. This signal switches to a TTL “1” when the high volt-
age bus exceeds low-line condition during turn-on. Upon loss of input power, the bus voltage will drop, caus-
ing the AC OK signal to go low. A minimum of 3 ms holdup time is provided for a 1200W load following the
loss of the AC OK signal.
Figure 2. AC OK Output Circuit
Rev. 05/11/2012 Mission Power Solutions (760) 631-6846 [email protected] Pg. 6
Javelin I & II Power Supply Operator’s Manual
Positive
Return
+5V
AC OK
2.5K
J2-6 AC Power OK
J2-4 Signal Return
PN2222
