Capacitor Life Warning Signal (Wac) (C021 To C026); Communication Line Disconnection Signal (Ndc) (C021 To C026, C077) - Hitachi L700 SERIES Instruction Manual

Chapter 4 Explanation of Functions
4.2.67 Capacitor life warning signal (WAC)
The inverter checks the operating life of the capacitors on the
internal circuit boards on the basis of the internal temperature
and cumulative power-on time.
You can monitor the state of the capacitor life warning (WAC) signal by using the life-check monitoring
function (d022).
If the WAC signal is output, you are recommended to replace the main circuit and logic circuit boards.
Item
Terminal function
Alarm relay terminal function
4.2.68 Communication line disconnection signal (NDc)
This signal function is enabled only when ModBus-RTU has been
selected for the RS485 communication.
If a reception timeout occurs, the inverter continues to output the
communication line disconnection signal until it receives the next
data.
Specify the limit time for reception timeout by setting the communication trip time (C077).
For details, see Section 4.4, "Communication Functions."
External control equipment
Monitoring timer
Communication line
disconnection signal (NDc)
Item
Terminal function
Alarm relay terminal function
Communication trip time
Function code
C021 to C025
C026
Inverter
Function code
C021 to C025
C021 to C025: Terminal [11] to [15] functions
C026: Alarm relay terminal function
Data or range of data
39
Communication trip time
(C077)
Data or range of data
32
C026
C077 0.00 to 99.99 (s)
4 - 70
Related code
Description
WAC: Capacitor life warning signal
(for on-board capacitors)
Related code
C021 to C025: Terminal [11] to [15] functions
C026: Alarm relay terminal function
C077: Communication trip time
Description
NDc: Communication line
disconnection signal
Setting of the limit time for
reception timeout