Rockwell Automation 20G PowerFlex 750-Series AC Drives - Manual (Page 112)

112 Rockwell Automation Publication 750-RM002B-EN-P - September 2013
Chapter 2 Feedback and I/O
Analog Input Loss Detection
Signal loss detection can be detected for each analog input. P47 [Anlg In Loss
Sts] bits 0, 1, 2 indicate if the signal is lost. Bit 0 indicates that one or both signals
are lost. P53 [Anlg In0 LssActn] and P63 [Anlg In1 LssActn] defines what action
the drive takes when loss of any analog input signal occurs.
Selects drive action when an analog signal loss is detected. Signal loss is defined as
an analog signal less than 1V or 2 mA. The signal loss event ends and normal
operation resumes when the input signal level is greater than or equal to 1.5V or
3 mA.
• “Ignore” (0) – No action is taken.
• “Alarm” (1) – Type 1 alarm indicated.
• “Flt Minor” (2) – Minor fault indicated. If running, drive continues to
run. Enable with P950 [Minor Flt Cfg]. If not enabled, acts like a major
fault.
• “FltCoastStop” (3) – Major fault indicated. Coast to Stop.
• “Flt RampStop” (4) – Major fault indicated. Ramp to Stop.
• “Flt CL Stop” (5) – Major fault indicated. Current Limit Stop.
• “Hold Input” (6) – Holds input at last value.
• “Set Input Lo” (7) – Sets input to P52 [Anlg In0 Lo] or P62 [Anlg In1
Lo].
• “Set Input Hi” (8) – Sets input to P51 [Anlg In0 Hi] or P61 [Anlg In1
Hi].
If the input is in Current mode, 4 mA is the normal minimum usable input value.
Any value below 3.2 mA is interpreted by the drive as a signal loss, and a value of
3.8 mA is required on the input for the signal loss condition to end.
If the input is in Unipolar Voltage mode, 2V is the normal minimum usable input
value. Any value below 1.6V is interpreted by the drive as a signal loss, and a value
of 1.9V is required on the input for the signal loss condition to end. No signal loss
detection is possible while an input is in Bipolar Voltage mode. The signal loss
condition never occurs even if signal loss detection is enabled.