Date Code 20020129
Installation
2-11
SEL-387E Instruction Manual
Output Contacts
Connect output wiring to the SEL-387E Relay main board eight standard independent output
contacts, OUT101 through OUT107 and ALARM. Standard independent dry output contacts are
not polarity dependent; the left side of Figure 2.7 shows these contacts as they would appear on a
terminal block version.
Figure 2.7: Standard Independent Output Contact Representation
Connect output wiring to any of the additional output contacts OUT201–OUT212 you need for
your application. On the additional interface board, you have the option of either standard or
high current interrupting contacts. High current interrupting contacts are polarity dependent. A
plus polarity mark next to the terminal requiring positive dc voltage identifies these contacts on a
relay rear panel. The right side of Figure 2.7 shows this polarity mark for high current
interrupting contacts. Ensure correct polarity; reversed polarity causes a short circuit to appear
across the contact terminals.
Communications Port
Refer to Table 2.1 for a list of cables that you can purchase from SEL for various communication
applications. Refer to
Section 7: Serial Port Communications and Commands
for detailed
cable diagrams for selected cables.
Note
: Listing of devices not manufactured by SEL is for the convenience of our customers.
SEL does not specifically endorse or recommend such products nor does SEL guarantee
proper operation of those products, or the correctness of connections, over which SEL
has no control.
The relay rear panel provides pin definitions for Ports 1, 2, 3, and 4. Refer also to
Section 7:
Serial Port Communications and Commands
for more serial port details. Port 1 is an EIA-485
protocol connection on the rear of the relay. Port 1 accepts a pluggable terminal block that
supports wire sizes from 24 AWG to as large as 12 AWG. The connector comes with the relay.
Ports 2, 3, and 4 are EIA-232 protocol connections with Ports 2 and 3 on the rear of the relay and
Port 4 on the front of the relay. These female connectors are 9-pin, D-subminiature connectors.
You can use any combination of these ports or all of them simultaneously for relay
communication.
For example, to connect the SEL-387E Relay Ports 2, 3, or 4 to the 9-pin male connector on a
laptop computer, order cable number C234A and specify the length needed. Standard length is
eight feet. To connect the SEL-387E Relay Port 2 to the SEL-2020 or SEL-2030
Communications Processor that supplies the communication link and the time-synchronization
signal, order cable number C273A and specify the length needed. For connecting devices at
more than 100 feet, fiber-optic transceivers are available. The SEL-2800 family of transceivers
