Alarms
7300A User Manual
5-4
5.3. LOAD MONITORING
Note:
• Thermal faults are signalled by the ‘T°’ LED if one of the alarm options or one of
the control options (except V2 and OL) is fitted. The unit is protected against
thermal faults whether or not they are signalled.Thermal faults are signalled by
the alarm relay if one of the alarm options is fitted.
• The DLF LED flashes in particular ways to indicate the number of the controlled
channel (of the three thyristor channels) on which load failure (TLF or PLF) has
occurred.
GRF
DLF
CHK
T
°
SET
Red LED:
'Overheating' (
≥
80 A)
Red LED:
'Serious faults'
Orange LED:
'Partial Load Failure'
DLF alarm
adjustment and diagnostic
push button
Figure 5-1 Layout of front panel LEDs with ‘GRF’ and/or ‘DLF’’ option
LED State
Firing
Temps de
Fault
‘T°’
‘GRF’
‘DLF’
‘HEAT’
stopped
réaction
red
red
orange
green
typique
Partial Load Failure
OFF
OFF
Flashing
(PLF)
ON
No 5 s to 13 s
Total Load Failure
OFF
ON
Flashing
or
(TLF)
Flashing
Thyristor Short-Circuit OFF
ON
OFF
(THSC)
Over-temperature (T°) ON
OFF
OFF
OFF
Yes
Table 5-1 LEDs for serious alarms or faults with ‘GRF’and/or ‘DLF’ options
Two diagnostic options are available :
• GRF option (Gross Fault) which permits to detect the following serious faults :
Total Load Failure : TLF
Thyristor Short-Circuit : THSC
Over Heating : T° (for units
≥
125 A only)
• DLF option (Diagnostic Load Failure), presents the same fault detection as GRF option
with in addition, the Partial Load Failure detection (PLF).
