Ecf Alarm (Caused By Logic Discrepancy) And Inverter Output State - Fuji Electric FRENIC-HVAC User Manual

Figure 11.7 shows the timing scheme to apply when the emergency stop button is turned ON with the
inverter running. Input to the EN1 and EN2 goes OFF, bringing the inverter into the Safe Torque Off
(STO) state and coasting the motor to a stop.
Figure 11.7 Inverter Output State when the Emergency Stop Button is Turned ON with the Inverter Running
11.1.4.5

ECF alarm (caused by logic discrepancy) and inverter output state

Turning the emergency stop button ON turns EN1 and EN2 inputs OFF and brings the inverter into the
Safe Torque Off (STO) state. When a discrepancy of EN1 and EN2 inputs occurs during a time longer
than 50 ms, the inverter interprets it as a logic discrepancy outputting an ECF alarm on the screen of the
standard keypad; if it is shorter than 50 ms, no alarm occurs. The alarm can be reset by removing power of
the inverter.
Figure 11.8 shows the timing scheme when the signals of EN1 and EN2 inputs are not simultaneous so
that an alarm ECF occurs.
Figure 11.8 ECF Alarm (Caused by Logic Discrepancy) and Inverter Output State
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