Asterion DC Multioutput ASA Series Operational Manual
M330516-01
2-15
Output voltage sensing is user-selectable to be either local sense or remote sense.
Sensing provides the signal for measurement of the output voltage and determines
the physical point where the output voltage is precisely regulated. Local and Remote
sense both are at the rear panel output connector, while remote sense is at the load,
through a cable connection from the rear panel remote sense Pin S+ and S-. Based
on the user selection (local or remote) corresponding sense signal is used by the
controller as the voltage feedback. Figure 2-7, shows the remote sense connector at
the rear panel of the power supply.
Remote sensing is used to compensate for the voltage drop that occurs across the
wires connecting the load to the output of the power source. A separate pair of wires
is routed to measure the voltage at the terminals of the load where precise regulation
of the output voltage is desired. The remote sense leads are connected at the remote
sense connector on the rear panel; refer Figure 2-7. Connect the terminal, Sense
Positive (S+), to the point at the load that is connected to the Output Positive terminal,
and the terminal, Sense Negative (S-), to the point at the load that is connected to
Output Negative terminal.
On selecting the remote sense, if the difference between the remote sense and the
local sense exceeds more than 5% of the rated output voltage, then the unit would go
to fault state. The fault can arise due any of the following conditions.
1. If the remote sense is selected and the remote sense wiring is not done to the
power supply unit.
2. If the remote sense is connected in the reverse polarity.
3. If the load cable drop exceeds 5% of the rated output voltage.
On the remote sense fault condition, the output voltage would get programmed to zero.
2.10
Wire Gauge Selection
Care must be taken to properly size all conductors for the input and output of the power
source. This section provides guidance in the selection of wire size.
CAUTION!
Use wire with Class B or C stranding. Fine-stranded (flexible) wire should not be
used unless crimp-on lugs or ferrules are utilized that are approved for fine-stranded
cables.
2.10.1
Wire Size
The tables below will assist in determining the appropriate wire size for both the input
and output connections. Table 2-8 gives minimum recommended wire size; these
recommendations are for 30
°
C ambient, and for copper wire only. This table is derived
from the National Electrical Code and is for reference only. Local laws and conditions
may have different requirements. For higher ratings, wires can be paralleled; refer to
the National Electrical Code for guidelines.
