Low-Current Indication (Loc) Signal (C021,C026,C038,C039); Inverter Ready Signal (Irdy) (C021,C026) - Hitachi NES1-004SB Quick Reference Manual

7.8.16 Low-current indication (LOC) signal
The inverter outputs the low-current indication (LOC) signal when the inverter output current falls to the
low-current indication signal detection level (C039) or less.
You can select one of the two signal output modes with the low-current indication signal output mode
selection (C038). In one mode, the LOC signal output is always enabled during the inverter operation. In
the other mode, the LOC signal output is enabled only while the inverter is driving the motor for
constant-speed operation.
Item
Terminal function
Alarm relay terminal function
Low-current indication signal
output mode selection
Low-current indication signal
detection level
(*1) When 01 (control circuit terminal) is selected as frequency source setting (A001), there is a case that
inverter does not recognize the speed as constant value due to sampling. In this case, adjusting is to be
made by setting C038=00 (valid during operation) or increasing analogue input filter (A016).
Output current (A)
Low-current indication
signal detection level
(C039)
Low-current
indication signal
7.8.17 Inverter ready signal (IRDY)
The inverter outputs the inverter ready (IRDY) signal when it is ready for operation (i.e., when it can
receive an operation command).
- The inverter can recognize only the operation command that is input while the IRDY signal is output.
- If the IRDY signal is not output, check whether the input power supply voltage (connected to the R, S,
and T terminals) is within the range of specification.
Item
Terminal function
Alarm relay terminal function
7.8.18 Forward rotation signal (FWR)
The inverter continues to output the forward rotation (FWR) signal while it is driving the motor for forward operation.
The FWR signal is turned off while the inverter is driving the motor for reverse operation or stopping the motor.
Item
Terminal function
Alarm relay terminal function
Function code Data or range of data
C021
C026
C038
0.0 to "2.0 x rated
C039
current" (A)
ON
Function code Data or range of data
C021
C026
Function code Data or range of data
C021
C026
7 - 73
Chapter 7 Explanation of Functions
43 LOC: Low-current indication signal
Enabling the signal output during
00
operation
Enabling the signal output only
01
during constant-speed operation (*1
Setting of the threshold current level
at which to output the low-current
indication signal
ON
50 IRDY: Inverter ready signal
51 FWR: Forward rotation signal
Description
Description
Description