Mitsubishi Electric MELSEC Q Series User Manual page 12

Precautions for security
Precautions for tag function
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(3) Time handled by Web server module (Refer to Section 3.9)
Transfer delay may occur since the Web server module acquires the clock data
from CPU No.1 at the following timings.
• When the programmable controller is powered off and then on or CPU module is
reset
• Once per minute
(1) Security of the Web server module
The Web server module supports the basic authentication (account setting) by the
user name and password and the IP filter function, however, it does not prevent all
of illegal access from the outside.
Preventive measures must be taken by users against illegal access to ensure the
programmable controller system safety. (Refer to Section 4.6.5 (3))
(2) Remote password function of QCPU
The remote password function of the QCPU is not used for the Web server
module.
When restricting access to the QCPU, use the user authentication function of the
Web server module.
(1) Tag setting and component setting (Refer to Section 6.3.3)
(a) When a component setting is deleted, the settings of the components after
the deleted setting No. are shifted up.
When the component has been set in the user part of the user screen creation
function, reexamine the parameters since the setting No. is changed. (Refer to
Chapter 7 for user part details.)
(b) If a component has a wrong device number in the component setting, the
other component that will obtain the device of the same access target CPU
will result in an error. Check the device number set in the component setting.
(c) If the data type is set as "String" in the component setting, device values
may be replaced.
(2) Tag sampled at high speed
(a) Be sure to create a user-set system area in the program memory of the
control CPU. (Refer to Section 6.3.3 REMARKS.)
(b) "Sampling: High speed" can be registered to only one tag. (Multiple setting is
not allowed)
(c) The access target CPU of the tag component selected to execute "Sampling:
High speed" is the access target CPU setting No. 1 (control CPU). (Fixed)
(d) Total points of 96 or less can be set for the devices of the tag component
selected to execute "Sampling: High speed".
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