GE Power Management
ALPS Advanced Line Protection System
9-1
9 SERVICING
9.1 SPARES
9
9 SERVICING 9.1 SPARES
9.1.1 DESCRIPTION
There are two servicing methods for the ALPS:
•
Spare board replacement.
•
Component level repair.
The preferred method is board replacement using the ALPS automatic self-tests to isolate failed boards. When the defec-
tive board is found, it can be replaced with a spare, and the system can be returned to service. This method typically yields
the shortest system down time. To further reduce down time, we recommend keeping a complete set of spare boards at the
maintenance center.
We do not recommend servicing the relay at the component level. This requires a substantial investment in test and repair
equipment and in technical expertise, and usually results in longer down time than board replacement. For those who do
wish to trouble-shoot to the component level, drawings can be requested from the factory. When you request drawings, you
must supply the following information:
•
The name of the board. This is found on the component side of the printed circuit board with the assembly number and
revision.
•
The assembly number of the ALPS is an eight-digit number with a letter inserted between the fourth and fifth digit and
with a group-identification suffix, such as 0215B8011G001.
•
The revision number is found adjacent to the assembly number of the board.
Power down the relay by turning off the front panel power switch and disconnecting power from the rear
connector before disassembling the unit. High voltage levels can be accessed at the power supply inputs.
9.1.2 SERVICING WITH THE RELAY SELF-TEST
The ALPS automatically performs tests of major functions and critical hardware components and reports their status via the
LUI Display, status LED and the non-critical and critical alarm contacts. The failure report is dependent on the type or level
of the failure. Some failures operate the critical alarm contact and the status LED, while others only operate the non-critical
alarm contact.
There are three levels of self-test performed by the ALPS:
1.
The first level indicates severe relaying failures, indicated by a FAIL message on the display, the critical alarm contact
opening, and the status LED turning red. These failures indicate that the relay is not providing protection.
2.
The second level displays warning messages. They are indicated by a WARN message on the display and closure of
the non-critical alarm contact. These failures indicate that the relay is still providing some degree of protection.
3.
The third level indicates system status errors that are due to power system errors (Trip Circuit Open) or are caused by
an ALPS command that disables the relay (Disable Outputs). They are indicated by the closing of the non-critical alarm
contact, a red LED, or by the opening of the critical alarm contact. However, nothing is displayed until the Information
Status command is issued.
The types of self-tests performed are described in the Chapter 1: PRODUCT DESCRIPTION. The components tested dur-
ing the start-up self-tests are listed in Table 9–1. The components tested during run-time background and foreground self-
tests are listed in Tables 9–2 and 9–3, respectively
CAUTION
