S

Scalable UPS A UPS that allows for expandability; for example, enables a UPS to accommodate a larger load by purchasing additional power modules.

Simple Network Management Protocol (SNMP) A request-response protocol that collects management information from network devices and provides a way to set and monitor configuration parameters.

Sine Wave The sinusoidal wave form exhibited by alternating current.

Single-Phase Power (1Ø) Power that is provided by a single source which normally includes one hot lead and a grounded (neutral) return line.

Slope Discrimination Method A design format that causes the Over Voltage Shutdown set point to fall with increasing load.

SNMP Simple Network Management Protocol

Square Wave Output waveform generated by very basic, low-cost UPSs. Functions adequately for less sensitive loads, but may not provide acceptable quality input for some types of electronic equipment.

Standby Power System See Off-Line UPS.

Start-On-Battery Enables user to power up UPS in the absence of utility power.

Start Up Delay The interval between power on and the start of current walk in. It is the sum of the Primary Enable Delay and the fixed and adjustable portions of the Output Enable Delay.

Status LEDs Light Emitting Diodes (LEDs) that show the status of the UPS when they light up or turn off.

Step Wave (Modified Sine wave) Enhanced version of square wave that provides adequate input for some more sensitive loads, but still not as high quality as a sine wave.

Supervisory Module The module that monitors and controls the operation of the DC power system.

Surge A transient (or momentary) wave of current, potential, or power in an electric circuit.

System Voltage The nominal voltage of the power system, equal to the nominal voltage of the rectifier modules. 48 V or 24 V.