Hitachi NJI-350B - Manual (Page 234)

Chapter 9 PLC Operation
9-1
Chapter 9 PLC Operation
The operating status and stop status of the MICRO-EH can be switched through various types of operations. This feature
is shown in Figure 9.1.
Stop status
Switch “STOP” or
operation definition
input “OFF”
Switch “RUN” and
operation definition
input “ON”
Switch “STOP”
Switch “RUN”
Designate operation definition input
Cancel operation definition input
Stop status Operating status
Caution
The MICRO-EH cannot handle a REMOTE
specification. A 10-point type CPU becomes
the RUN mode when the RUN input is On.
Figure 9.1 Transitional diagram between operating and stop statuses
The MICRO-EH can be operated or stopped under the conditions as shown in Figure 9.1. If an error is detected during
operation or stop, output is shut off, an error is displayed and the MICRO-EH stops. There are fatal error, serious error,
minor error and warning. The operating status for each error is listed in Table 9.1.
Table 9.1 Description of each error and operating status
Classification Description Run/Stop
Fatal error This indicates there is a fatal and unrecoverable error, such as a power
supply problem, microcomputer error, system ROM error, system RAM
error and system path error. Stops
Serious error This indicates there is an error such as data memory problem, system
program problem, user memory problem, user memory size error,
syntax/assembler error, etc., which may cause a malfunction if operation is
continued. Stops
Minor error These are errors such as I/O information verify error, remote problem,
congestion error, excessively assigned I/O points, etc. The operation may be
continued when a continue operation is set by the user programs. Stops
(continued operation
is possible if
specified)
Warning These are problems such as a transfer error, backup memory write problem,
etc. where it is possible to continue the operation. Operation continues