Alpha Technologies PowerAgent SC3 - Manual (Page 5)

PowerAgent TM SC3 Site Controller Document # 700-000014-01 Rev 2
Installation and Operation
Phoenix Broadband Technologies, LLC 10/28/2010
Page 5 of 57
1.3 Important Symbols
The following symbols are used in this document.
1.4 Definition of Terms
Admittance – The inverse of Impedance in units of Siemens. Admittance is a measure of how
easily a circuit or device will allow a current to flow. Resistance is a measure of the opposition of
a circuit to the flow of a DC current, while impedance takes in to account not only the resistance
but AC effects (known as reactance) as well. Likewise, admittance is not only a measure of the
ease with which a DC current can flow (conductance, the inverse of resistance), but also takes in
to account the AC effects of susceptance (the inverse of reactance).
Battery – A collection of jars connected in series. A battery is sometimes referred to as a Battery
String or String in this document.
Cell – A collection of plates connected to a single positive and single negative terminal immersed
in electrolyte in a single container. The cell may have multiple positive and negative connections
but they connect to a single set of plates. A lead acid cell produces approximately 2.1 volts.
Jar – A collection of one or more cells connected in series in a single housing. A 12 volt jar
contains 6 cells. A Jar is commonly and incorrectly referred to as a battery.
P-Bus – A Phoenix proprietary communications interface and protocol used to connect devices to
the Site Controller for the purpose of providing additional input, output, and measurement
capability.
CAUTION!
The use of CAUTION indicates safety information intended to prevent damage and/or injury
NOTE:
A NOTE to provide additional information to help complete a specific task or procedure