Xantrex XKW 12-150, Operating Manual

Page: 43 / 90

Installation
Load Connection
Revision A
41
Load
Connection
and
Grounding
Proper connection of distributed loads is an important aspect of power supply
application. A common mistake is to connect leads from the power supply to one
load, from that load to the next load, and so on for each load in the system. In this
parallel power distribution method, the voltage at each load depends on the current
drawn by the other loads and DC ground loops are developed. Except for low current
applications, this method should not be used.
The preferred way to distribute power is by the radial distribution method in which
power is connected to each load individually from a single pair of terminals
designated as the positive and negative distribution terminals. The pair of terminals
may be the power supply output terminals, the terminals of one of the loads or a
distinct set of terminals especially established for distribution. Connecting the sense
leads to these terminals will compensate for losses and minimize the effect of one
load upon another.
Inductive Loads To prevent damage to the power supply from inductive
kickback, connect a diode (rated at greater than the supply’s output voltage and with
a current surge rating greater than or equal to the supply’s output current rating)
across the output. Connect the cathode to the positive output and the anode to return.
Where positive load transients such as back EMF from a motor may occur, connect
a transorb or a varistor (with a breakdown voltage approximately 10% higher than
the rated supply output) across the output to protect the power supply.
WARNING
Exercise caution when using and servicing power supplies. High energy levels can
be stored at the output voltage terminals on all power supplies in normal operation. In
addition, potentially lethal voltages exist in the power circuit and the output connector
of power supplies which are rated at 40V and over. Filter capacitors store potentially
dangerous energy for some time after power is removed.
TM-25OP-01XN.book Page 41 Monday, April 5, 2004 8:58 AM