GE 745 Instruction Manual page 60

HARDWARE INTERFACE
4–6
values. A passcode of "0" effectively turns off the passcode feature - in this case only the
access jumper is required for changing setpoints. If no key is pressed for 5 minutes, access
to setpoint values will be restricted until the passcode is entered again. To prevent setpoint
access before the 5 minutes expires, the unit may be turned off and back on, the access
jumper may be removed, or the
"Restricted". The passcode cannot be entered until terminals D9 and D10 (access
terminals) are shorted. When setpoint access is allowed, the Setpoint Access LED indicator
on the front of the 745 will be lit.
Setpoint changes take effect immediately, even when transformer is running. However,
changing setpoints while the transformer is running is not recommended as any mistake
may cause a nuisance trip.
The following procedure may be used to access and alter setpoints. This specific example
refers to entering a valid passcode to allow access to setpoints if the passcode was "745".
1. Press the MENU key to access the header of each menu, which will be displayed in the
following sequence:

SETPOINTS [ ]

ACTUAL VALUES [ ]

TARGET MESSAGES [
2. Press the MENU key until the display shows the header of the setpoints menu, then
press the MESSAGE RIGHT or ENTER key to display the header for the first setpoints
page. The set point pages are numbered, have an 'S' prefix for easy identification and
have a name which gives a general idea of the settings available in that page.
Pressing the MESSAGE keys will scroll through all the available setpoint page headers.
Setpoint page headers look as follows:
 
SETPOINTS [ ]
S1 745 SETUP
3. To enter a given setpoints page, press the MESSAGE RIGHT or ENTER key. Press the
MESSAGE keys to scroll through sub-page headers until the required message is
reached. The end of a page is indicated by the message
of a page is indicated by the message
4. Each page is broken further into subgroups. Press MESSAGE UP or DOWN to cycle
through subgroups until the desired subgroup appears on the screen. Press the
MESSAGE RIGHT or ENTER key to enter a subgroup.
 
PASSCODE [ ]
5. Each sub-group has one or more associated setpoint messages. Press the MESSAGE
UP or DOWN keys to scroll through setpoint messages until the desired message
appears.
ENTER PASSCODE
FOR ACCESS:
setpoint may be changed to
SETPOINT ACCESS
]
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745 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 4: INTERFACES
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