ABB AC 800M

Section 4 Operation Verification of Redundant CPU
3BSE 027 941 R301 117
Verification of Redundant CPU
Check, in redundant configuration, the following LED indicators on PM861/PM864
(see Table 19 on page 117).
To check that the redundancy, i.e. the backup CPU, is working correctly, perform a
manual switch-over from the Primary CPU to the Backup CPU. A manual switch-
over is initiated by:
• resetting the Primary CPU.
• powering off the Primary CPU.
Check that the yellow DUAL LED subsequently lights up on both CPUs, and that
the PRIM LED lights up on the former Backup CPU now acting as Primary CPU.
For other units see Table 18 on page 115.
Table 19. AC 800M Controller (PM861/PM864) – Verification of Satisfactory
System Operation in Redundant configuration
LED Indicator Status
AC 800M Controller
Status
Primary CPU Back-up CPU
PRIM(ary) yellow ON PRIM(ary) yellow OFF OK
DUAL yellow ON DUAL yellow ON OK
The RCU Link Cable must NEVER be removed from the primary Processor
Unit during operation. Removal of the cable may cause the unit to stop.