6
There are three ways of communicating with the SEL-751A. You can communicate with the relay using the Human
Machine Interface (HMI) on the front panel, remote communications, or a direct computer connection. For direct serial
communications, the computer must have a serial port (or USB port if using SEL-C662 USB cable) and the operating sys-
tem should be Windows
®
2000 or newer. A standard EIA-232 crossover cable or an SEL-234A cable will also be required.
HMI Pushbuttons
Computer Connection Steps
Step 1. Connect the PC and the relay using a serial communications cable.
Step 2. Apply power to both the PC and the relay.
Step 3. Open a terminal emulation program.
Option 1:
AC
SEL
ERATOR
QuickSet SEL-5030 Software
Open
AC
SEL
ERATOR
QuickSet and proceed to
. If you do not
have
AC
SEL
ERATOR
QuickSet, you can download the program from
www.selinc.com/sel-5030.htm. Refer to Section 3 of the SEL-751A
manual for more information about
SEL
ERATOR
QuickSet.
Option 2: HyperTerminal
To open HyperTerminal go to
Start > Programs > Accessories >
Communications > HyperTerminal
. Once there you will be prompted
to enter a name of your choice for the connection. Then you will choose
which port to connect through. Make sure you select the same port that
you connected the cable to, then click
OK
.
Step 4. Set the PC terminal emulation program to the same communications
port settings as shown in the figure to the right and click
OK
.
Step 5. Press the
<Enter>
key on the PC keyboard to check the
communications link. You should see the = prompt. If you do not see the
= prompt, check the cable connections, confirm that the settings in the
terminal emulation program are the default values, and that the
emulation mode is set to VT100.
Step 6. Once connected, you can set all other relay settings and obtain values as
needed. Refer to Section 6 in the SEL-751A manual for more
information.
Press the TARGET RESET pushbutton
to clear targets that have been alarmed.
Press the ESC pushbutton
to return to previous menu.
Press the directional (up, down, left, right)
pushbuttons to scroll through options.
Press the ENT pushbutton
for selection to see next menu.
ENT
ESC
TARGET
RESET
SEL-751A Relays are shipped with default passwords. To prevent unauthorized access, change default passwords to
private passwords at installation. SEL shall not be responsible for damage resulting from unauthorized access.
Communication With Relay
