Page 14
PCHS/TPCHS SERIES Quick-Set PowerCassette®
INSTALLATION & OPERATING MANUAL
Manual No. tpchs-2
pchs-tpchs-man-rev2-1214.indd
13.6 Remote Sensing.
Remote sensing connections for V1, V2 and V3 are made to the desig-
nated pins on the large Positronics connector. Remote sensing is not available on the low
current V4 and V5 outputs or on the S5V, 250 mA output. Remote sensing is used
to regulate the output voltage at the point of load by compensating for the voltage drop in
the wires to the load. Each +Sense lead must be connected to the + side of the load and each
-Sense lead to the -side of the load. The sense leads should be color-coded, twisted pairs of
AWG no. 22 or 24 copper wire. See Figure 8. Remote sensing can compensate for a total
voltage drop of 0.5V, or 0.25V per load wire. The sense leads should not exceed 10 feet (3
meters) in length. If remote sensing is not required, the sense leads may be left open for
local sensing at the output terminals. Be careful not to reverse the sense lead connections,
as this could damage the output.
Figure 8 - Remote Sensing Connection for Each V1, V2 or V3 Output
13.7 Control & Supervisory Signals.
All control and supervisory signals are accessible at the
large Positronics connector on the back of the unit. See Figure 5. The Global Inhibit (Pin 39)
should be connected through a 10k ohm resistor to the +5V Standby (Pin 26).See Section
16 for a complete description of these input and output signals.
13.8 Alarm Signals.
Among the control and supervisory signals are three logic alarms: Input
Power Fail, Output Power Good and Overtemperature Warning. These are logic signals
referenced to Signal Ground, Pin 22 on the large Positronics connector. Input Power Fail is
a logic LO when AC or DC input power is present. This signal goes to a HI 4 milliseconds
before the outputs go out of regulation and stays HI for typically 15 msec. Output Power
Good is a HI when V1 to V3 outputs are present and in regulation. Overtemperature Warning
is normally a logic HI but goes to a LO when the internal air temperature reaches a critical
level just prior to the unit shutting down. These logic signals are provided from transistor
interfaces with internal pull-up resistors to an in5V level.
13.9 AC and DC Inputs.
It should be noted that the AC and DC input pins are mutually
exclusive. In other words, an AC input PowerCassette does not have the small Positronic
DC input connector (pins 48 to 50). Likewise the DC input PowerCassette has no connec-
tions to the AC input terminals on the large Positronics connector (pins 46 and 47).
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com
