Installation
8
2 Installation
2.1
Quick Reference Guide
This section summarizes the required procedures to install the
trip unit before energizing the breaker. Follow the steps listed
below to install the SB Energy-Comm trip unit.
1.
Unpack and inspect the trip unit as described in
Section
2.2, Unpacking and Inspection.
2.
Select a power source for the trip unit. See
Section 2.3,
Selecting a Power Source
.
3.
Select and install the proper potential transformer (PT) for
your system. See
Section 2.4, Selecting a PT
.
4.
Wire the trip unit as described in
Section 2.5, Wiring
.
5.
Install the trip unit into the breaker. The step-by-step pro-
cedure is described in
Section 2.6, Installing the Trip
Unit in a Systems Breaker
.
6.
Select and install the rating plug. See
Section 2.7, Insert-
ing and Removing the Rating Plug
. Be sure the plug has
the proper rating.
7.
Read
Section 3, User Interface
to familiarize yourself
with the front panel controls and display.
8.
Configure the trip unit’s system parameters, including fre-
quency, wiring configuration, PT rating, short circuit pro-
tection type, and neutral CT. Instructions on setting these
parameters are listed in
Section 4.2, Setting System
Configuration Parameters
.
9.
Configure the trip unit’s overcurrent protection. Instructions
on setting these parameters are listed in
Section 5, Over-
current Protection Configuration
.
These are the minimum configuration requirements before
energizing the breaker. Additional configuration parameters
are described in
Section 4.3, Setting Other Device Parame-
ters
and in
Sections 6
through
10
inclusive.
2.2
Unpacking and Inspection
When unpacking the SB Energy-Comm trip unit, inspect the
device for any damage and report any problems to your local
Siemens representative.
The SB Energy-Comm trip unit has been factory tested to strin-
gent requirements. The Siemens factory that produced this trip
unit has a quality system that is certified to an ISO 9000 inter-
national standard.
All settings are factory preset to the minimum values.
2.3
Selecting a Power Source
The SB Energy-Comm trip unit depends either on power from
the current transformers (CTs) or independent control power.
The protective functions use the power from the CTs; the meter-
ing and communications require separate control power from
an external power supply. This requirement allows communica-
tion with the trip unit during all load current conditions, even
with the circuit breaker switched off.
The ratings for the power supply are:
•
Input: 110V AC = SBEPS Catalog Number
24V DC = SBEPS24 Catalog Number
•
Output: +5V DC @ 4A,
+12V DC @ 0.3A, -12V DC @ 0.3A
2.4
Selecting a PT
A potential transformer (PT) module is required to provide volt-
age signals to the trip unit for metering functions and provides
isolation from the primary circuits. Class CC IA 600V fuses can
be added during installation to protect against internal PT mod-
ule faults. The PT modules are encapsulated in polymeric
material to protect the transformer windings and withstand
mechanical vibration. The PT module’s primary inputs are from
the three phases plus neutral. For three-wire systems, the neu-
tral conductor input is not used. To choose a PT module, select
the one rated closest to, but higher than the rated voltage:
2.5
Wiring
Before operation, the SB Energy-Comm trip unit must be properly
wired to the external power supply and the PT module. Panel-
boards manufactured by Siemens are shipped with all required
wiring. Retrofit applications require a retrofit kit, which includes
instructions for mounting and wiring the power supply and PT
module.
Figure 2.1
shows the proper wiring connections.
If you are connecting the SB Energy-Comm trip unit to an
ACCESS Host device, you must also connect the SEAbus RS-
485 cabling to the secondary disconnects or terminal blocks
as shown in
Figure 2.1
.
Refer to the
Individual Instruction Sheets
for wiring the vari-
ous accessories, the PT module, and the trip unit power supply.
Table 2.1
PT Module Selection
For System Voltage of:
Select This PT Module:
120/208V, 120/240V, 220V
SBPTM240
277/480V, 415V
SBPTM480
575V
SBPTM600
