User Instructions UM1M820BNA
Spec No. 1M820BNA (Model M820B) Issue AH, March 4, 2013
Spec No. 1M820DNA (Model M820D)
Chapter 2. Operation 75
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2.7.5 Paralleling the Existing and ACU+ Power Systems Admonishments
General Safety
Danger: YOU MUST FOLLOW APPROVED SAFETY PROCEDURES.
Performing the following procedures may expose you to hazards. These
procedures should be performed by qualified technicians familiar with the hazards
associated with this type of equipment. These hazards may include shock, energy,
and/or burns. To avoid these hazards:
a) The tasks should be performed in the order indicated.
b) Remove watches, rings, and other jewelry.
c) Prior to contacting any uninsulated surface or termination, use a voltmeter to
verify that no voltage or the expected voltage is present.
d) Wear eye protection, and use recommended tools.
e) Use double insulated tools appropriately rated for the work to be performed.
AC Input Voltages
Danger: This system operates from AC voltage capable of producing fatal electrical shock.
DC Input/Output Voltages
Danger: Connecting the ACU+ power system to an existing power system for “Power Split”
mode involves working on live equipment carrying live loads. This system
produces DC power and may require battery to be connected to it. Although the
DC voltage is not hazardously high, the rectifiers and/or battery can deliver large
amounts of current. Exercise extreme caution not to inadvertently contact or have
any tool inadvertently contact a battery terminal or exposed wire connected to a
battery terminal. NEVER allow a metal object, such as a tool, to contact more than
one termination at a time, or to simultaneously contact a termination and a
grounded object. Even a momentary short circuit can cause explosion and injury.
Remove watches, rings, or other jewelry before connecting leads. Cover any live
busbars with a canvas sheet to prevent short circuits caused by falling tools or
parts.
Preparing the Existing and ACU+ Power Systems
Install and turn-up the ACU+ power system as describe in the installation instructions furnished with
the power system.
Set the float voltage on both the existing and ACU+ power systems to the same level. Temperature
compensation functionality, if used, should be disabled on both power systems.
Paralleling the Systems
Connect the Battery and Battery Return busbars of the ACU+ Power System to the main charge
busbars (rectifier side of the shunt) on the parallel power system. Size the cable for the largest current
between systems.
Note 1: The connections between the two power systems should be done with power cables
appropriately sized to be capable of carrying the maximum current that can circulate
between the two power systems.