Hitachi WJ200-001S Instruction Manual page 281

474
Communication signal Disconnect Detect
This signal function is enabled only when ModBus-RTU has been selected for the
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
().
External control equipment
Monitoring timer
Communication line
disconnection signal (NDc)
Option Terminal
Code Symbol

NDc
Valid for inputs:
Required settings
Notes:
 The example circuit for terminal [11] drives a relay
coil. Note the use of a diode to prevent the
negative-going turn-off spike generated by the coil
from damaging the inverter's output transistor.
Function Name State
Communication
signal disconnect
detection
11, 12, AL0 – AL2

ON When there is a disconnection in communiciation
OFF When there is no disconnection in communiciation
Example for terminal [11] (default output
configuration shown – see
Inverter output
terminal circuit
Example for terminal [AL0], [AL1], [AL2] (requires
output configuration – see
Inverter logic
circuit board
AL0
Power
supply
See I/O specs on
Communication

trip time
Description
page 3-89):
NDc
CM2 11
RY
page 4-51 and 3-91):
NDc
AL1 AL2
Load
page 4-6