KEPCO HSP Series Operator Manual - Manual (Page 26)

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HSPSERIES OPR 050614
2.7.7 SIGNAL CONNECTIONS
The I/O Signal Connector, located on the rear panel of the HSP power supply (see Figure 2-3),
provides access for all programming inputs and status signal outputs. These signals provide the
user access to portions of the regulation control circuitry of the HSP and, as such, must be pro-
tected from radiated and conducted noise as well as from physical contact with non-valid driving
sources. The following subsections address specific programming signal applications; in gen-
eral, however, when accessing this connector from distant locations or high-noise environ-
ments, it is recommended that a shielded cable be used, with the shield terminated to the
system's single point ground.
a. Remote Error Sense
Twist positive and negative error sensing lines (pins 37,19) together, especially when a sig-
nificant distance separates the power supply and load.
b. External Voltage Programming (Voltage or Current)
Twist the programming signal line(s) (pins 18, 15, or both 18 and 15) with negative error
sensing line (pin 19); use shielded cable if possible.
c. External Resistance Programming (Voltage)
Twist both programming lines (pins 17, 35) together; use shielded cable if possible.
d. Remote Inhibit Controls (RC1, RC2)
Twist either (or both) programming lines (pins 7,8) together with AUXRTN (pin 25); if 5VAUX
is used to power the external inhibit control circuitry, include 5VAUX line (pin 26) in twist.
2.8 MECHANICAL KEYING
When used with Kepco plug-in rack adapters (RA 60 and similar), HSP power supplies can
be configured for extraction from and insertion to an active system, or “hot-swap”. Hot-
swapping requires the use of series blocking diodes for each output (see Figure 2-7). The
HSP incorporates a mechanical keying system to be used in conjunction with the plug-in
rack adapters to prevent installation of any but the correct model HSP in a given position.
The keying mechanism is comprised of (7) holes, each corresponding to an HSP model; all
holes are plugged except for the “keyway,” thus providing the keying function in conjunction
with a pin installed in each rack adapter position. All HSP power supplies are keyed by volt-
age at the factory. It is essential that the user: 1) not remove or alter the keyway plugs,
and 2) replace any plugs which are inadvertently removed in accordance with the
view shown in Figure 2-3. To change module keying, see instructions accompanying the
HSP series plug-in rack adapters.
2.9 RETAINING LATCHES
HSP series power supplies are provided with (2) retention latches located at each side of the
bottom edge of the front panel (see Figure 2-1). These latches work in conjunction with the HSP
series plug-in rack adapters to prevent unauthorized or inadvertent module extraction from an
operating power system. The latch is engaged by loosening the cap-head screw approximately
1/2 turn CCW (use 5/32" hex key) and sliding the latch down to the bottom of the slot, then
retightening the cap-head screw CW until snug. DO NOT OVERTIGHTEN! To release, follow
the same procedure, except lift the latch to the top of the slot. Be sure to move the latch com-
pletely up or down to ensure full engagement and disengagement of the latching mechanism.
When the HSP power supply is not installed in its plug-in rack adapter, it is recommended that
the latch be secured in the open (up) position to prevent damage.
NOTE: Retaining latches must not be used to secure the HSP power supply in the rack
adapter for shipping purposes.