Siemens SINAMICS S150 NEMA Operating Instructions Manual page 709

10.3.3 "External Fault 2"
Causes
Fault code F7861 "External Fault 2" is triggered when the braking resistor available with
options L61/L62/L64/L65 is subject to thermal overload, thereby activating the thermostat.
The drive is switched off with OFF2.
Remedy
The cause of the braking resistor overload must be eliminated and the fault code
acknowledged.
10.3.4 "External fault 3"
Causes
Fault code F7862 "External fault 3" is triggered when the braking unit fitted for options
L61/L62/L64/L65 triggers a fault. The drive is switched off with OFF2.
Remedy
The cause of the braking unit overload must be eliminated and the fault code acknowledged.
Converter cabinet units
Operating Instructions, 11/2017, A5E36652151A
Diagnostics / faults and alarms
10.3 Overview of alarms and faults
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