Hitachi L700 Series

Chapter 4 Explanation of Functions
4 - 70
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 Function code Data or range of data Description
Terminal function C021 to C025
39
WAC: Capacitor life warning signal
(for on-board capacitors)
Alarm relay terminal function C026
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."
Item Function code Data or range of data Description
Terminal function C021 to C025
32
NDc: Communication line
disconnection signal
Alarm relay terminal function C026
Communication trip time C077 0.00 to 99.99 (s)
Setting of the limit time for
reception timeout
C021 to C025: Terminal [11] to [15] functions
C026: Alarm relay terminal function
Related code
C021 to C025: Terminal [11] to [15] functions
C026: Alarm relay terminal function
C077: Communication trip time
Related code
(C077)
External control equipment
Inverter
Monitoring timer
Communication line
disconnection signal (NDc)
Communication trip time