YOKOGAWA FA-M3 Vitesse, Руководство пользователя

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3-5
IM 34M6H33-01E 1st Edition : July 1.2004-00
Lock Function
The Lock function is used to prevent inadvertent switching from Protected mode to
Configuration mode. If the MODE switch is accidentally turned from the PROTECT
position to the CONFIG position in locked state, the module remains in Protected mode.
At the same time, both the MST and NST lamps enter fast-blinking state to indicate an
invalid switch position.
- Unlock Function (Switching to Configuration Mode)
To release the module from a locked state, turn the MODE switch from the CONFIG
position to the SET position for more than 3 seconds. At about 3 seconds, the fast-
blinking MST and NST LED indicators stop blinking. If you then release the switch, the
module enters Configuration mode.
After switching to Configuration mode, if the MODE switch is then turned to the SET
position for more than 3 seconds, the module performs the alternative action of
registering the LDS to the LPS.
CAUTION
After switching between Protected mode and Configuration mode or registering the
slave configuration to the LPS during operation, the module enters offline mode (this can
be confirmed by checking the OFFLINE_READY* (X
□□□
17) input relay) for about 1
second, during which reading of inputs is suspended and output is turned off.
*: For details, see Table 5.1, "Input Relays".
Automatic Address Assignment Function
By default, the automatic address assignment function is enabled on this module. For
details on how to disable the automatic address assignment function, see Chapter 7.
When a slave that has failed due to hardware fault or some other reason is replaced
with a blank slave of the same type, the automatic address assignment function
automatically programs the blank slave with the address of the original slave that had
failed. Two slaves are considered to be of the same type if they have the same ID code
and I/O code.
When the module detects a failed slave in Protected mode, its NST indicator changes
from blinking to lit. If the automatic address assignment function is enabled, the module
scans the ASi line to find blank slaves, and read their types.
When the module finds a slave whose type is the same as that of the failed slave as per
its registration in the LPS on the module, it writes the address of the failed slave to the
blank slave. Communication then begins and the NST indicator returns to blinking state.
If the module is switched from Protected mode to Configuration mode when a failed
slave is present, automatic programming is suspended. However, when the module is
subsequently returned to Protected mode, automatic programming continues if failed
slave is still present.