AMETEK ReFlex - Manual (Page 109)

AC Power Supplies ReFlex Power™
4-24 M380056-01 Rev K
AC O UTPUT C ONNECTOR A CCESSORIES
• AMETEK P/N 5380450-01, ACPS Module, 9ft. Unterminated AC Output Cable Assembly
• AMETEK P/N 5380450-03, ACPS Module, Right Angle, 9ft. Unterminated AC Output Cable
Assembly
R EMOTE S ENSE
Remote sensing is used to compensate for the voltage drop that occurs across
the wires connecting the load to the output of the AC power supply module. A
separate pair of wires is routed to measure the voltage at the load terminals
where precise regulation of the output voltage is desired.
The remote sense leads are connected at the AC Output connector on the front
panel of the module. Refer to the subsection above, AC Outputs, for infor-
mation on connector pinout. Connect the SNS terminal to the load terminal
connected to the module OUT terminal, and the SNS-RTN terminal to the load
terminal connected to OUT-RTN terminal.
Special care is required in routing the sensing leads to prevent noise pickup or
coupling to the power leads; refer to the section, Noise and Impedance Effects.
The sense leads should be a twisted-pair of at least AWG #22 wire, and may
require shielding in high noise environments. Connect the shield to the shield
ground terminal, CHAS-GND, of the AC Output connector as required to
maximize its effectiveness.
If the remote sense leads are not connected, the AC module will continue to
operate but the voltage at the load will no longer be precisely regulated. An
internal resistor network exists within the module that connects the output
terminals to the remote sense terminals. This network provides the
measurement of the output voltage when the remote sense leads are not
connected. However, since the voltage is now measured at the output
terminals, the voltage drop of the load wiring would no longer be compensated.
Several conditions related to remote sensing are treated as faults and result in
shutdown of the output: short-circuiting of the remote sense terminals;
connecting the remote sense leads in reverse polarity; excessive line drop in
the load wires. When the fault condition is detected, shutdown will result with
the output voltage being programmed to zero and the output isolation/sense
relays being opened.