Internal Faults - ABB RELION REX640 Technical Manual

Section 3
Basic functions
3.3.1
98
GUID-C1CB83B9-C8C1-4FBC-AD6A-664E7684ACE4 V1 EN
Figure 19: Relay self-supervision status on Web HMI
In addition, the last boot reason and time are shown on both LHMI and WHMI.

Internal faults

When an internal relay fault is detected, relay protection operation is disabled and the
self-supervision output contact is activated. In the main unit, the main indication of an
internal fault is a flashing green Ready LED behind the power module, and on the
HMI, a rapidly flashing red Home button.
Different actions are taken depending on the severity of the fault. The protection relay
tries to eliminate the fault by restarting. In case of a permanent fault, the protection
relay stays in the internal fault mode. All other output contacts are released and locked
for the internal fault. The protection relay continues to perform internal tests during
the fault situation.
If the internal fault disappears, the fault indication LEDs stop flashing and the
protection relay returns to the normal service state.
The self-supervision signal output operates on the closed-circuit principle. Under
normal conditions, the protection relay is energized and the contact gap 3-5 in slot B
is closed. If the auxiliary power supply fails or an internal fault is detected, the contact
gap 3-5 is opened.
GUID-C9AF791D-D8F6-4768-A6D9-12FD192129CD V1 EN
Figure 20: Output contact
1MRS759142 C
REX640
Technical Manual