Accessories/Modifications, RL Breaker, Shunt Trip

480V Metal-Enclosed Switchgear

LV Power Circuit Breaker Trip Unit

General

Table 4.3 Static Trip III Trip Unit Functions

Table 4.5 Static Trip III Metering

Functions

Model

Function

III

IIIC

IIICP

IIICPX

Model

Self-Powered Overcurrent Protection

✓

Function

IIIC

IIICP

Phase Currents

✓

RMS Sensing

✓

Avg Phase Currents

✓

Switchable Thermal Memory

✓

Ground Current d

✓

Ground Fault Protection

opt

Neutral Current e

opt

LCD Target

✓

Phase Voltage f

—

✓

Protective Microprocessor Watchdog

✓

Avg Phase Voltage f

—

✓

Pickup LEDs

✓

Line Voltages

—

✓

Zone Interlocking a (For Short Time and Ground Fault)

opt

Avg Line Voltages

—

✓

Retrofit Universal Mounting Package

opt

—

✓

RS-485 Communications Port

—

✓

kW Demand

—

✓

Breaker Display Unit Port b

—

✓

kW Hours

—

✓

Communications Microprocessor Watchdog

—

✓

kW Hours Reverse

—

✓

Comm Watch LED

—

✓

kVA

—

✓

Backup Shadow Protection

—

✓

kVAR

—

✓

Trip Log

—

✓

kVAR Hours

—

✓

Alarm Relay Output a

—

opt

Power Factor

—

✓

Trip Unit Status Indication

—

✓

Frequency

—

✓

Breaker Position Indication

—

✓

Breaker Operation Counter

—

✓

Communication Open/Close/Trip ac

—

opt

Event Log

—

✓

Phase Current Metering

—

✓

Ground Current Metering d

—

✓

a Requires additional compartment mounted devices

Neutral Current Metering e

—

opt

and wiring to meet specific application.

Min/Max Current Log

—

✓

b Supports optional Breaker Display Unit accessory.

Power Metering Functions

—

✓

c Open command uses alarm relay output and restricts

use for other alarm functions. Close command

Min/Max Power Log

—

✓

requires electrically operated breaker.

Extended Protective Relaying

—

✓

d Included when ground fault protection specified.

e Requires “N” option and neutral current sensor.

Extended Trip Log

—

✓

f Only displayed for four wire systems.

Table 4.4 Static Trip IIICPX Protective Relay Functions

Setting

Typical Applications

Protective Function

Range

Motors

Generators

Mains

Current Unbalance

5 – 50%

✓

—

Voltage Unbalance

5 – 50%

✓

—

✓

Overvoltage

60 – 660V

—

✓

—

Undervoltage

60 – 660V

✓

—

Reverse Power

10 – 2000kW

—

✓

Overfrequency

50.0 –70.0 Hz

—

✓

—

Underfrequency

45.0 – 60.0 Hz

—

✓

—

480V

Switchgear

Metal-Enclosed

Accessories/Modifications

The tripping actuator is a low energy,

Operating

Shunt Trip

RL Breaker

Tripping Actuator

Table 4.6 Shunt Trip Coil Ratings

flux-shifting device that allows fast action

Nominal Control

Voltage

(Amperes)

Type RL circuit breakers feature several

tripping of the breaker.

Voltage

Range

Seal-In/Inrush

60 Hz

120

104 –127

1.65/7.7

options, including:

Shunt Trip

240

208 – 254

0.71/3.4

J Shunt Trip, (for MO breakers)

The shunt trip is used to electrically trip

28 – 56

5.45

Operation Counter

the circuit breaker from a remote device,

125

70 –140

2.76

such as pushbutton, switch, or relay. The

250

140 –280

1.85

Undervoltage Trip Device

shunt trip is standard on all electrically

Electrically Operated Interlock

operated breakers, optional on manually

When the coil is energized, the armature

J Automatic Trip Alarm Contact (with or

operated breakers. The shunt trip coil is

picks up and rotates the trip latch, there-

without Lockout Bell Alarm)

designed for a momentary duty cycle.

by tripping the breaker. A compression

Thus, an “a” type auxiliary contact switch

spring returns the armature to the normal

is used to interrupt the shunt trip circuit

position.

immediately after the breaker is tripped.

CSI Section 16470	Siemens Electrical Products and Systems	57
	Specification Guide