10 system extension and modification, 1 general information, 10 system extension and modification -47 – YSI IQ SensorNet 2020 XT Terminal User Manual
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System 2020 XT USB
Installation
3 - 47
ba76019e01
12/2012
3.10
System extension and modification
3.10.1 General information
The modular structure of the IQ S
ENSOR
N
ET
system makes it easy to
carry out subsequent extensions and modifications. The system
automatically identifies new active modules and includes them in the
list of modules. Added IQ sensors immediately deliver measured
values without the necessity for special settings.
Warning
When the system is switched on, if the MIQ/PS power supply
module is opened, there is a danger to life due to possible hazard
of electric shock from line voltage. There is also a danger to life
inside the relay output modules (e.g. MIQ/ CR3) if voltages are
applied to the relay contacts that may present a hazard of electric
shock. Before opening the MIQ modules, switch off the system
and all external voltages that present a hazard of electric shock
and secure the system against being inadvertently switched on
again.
Installation instructions
Note the following points in any system extension or modification:
Before any extension or modification, check that the planned
number of MIQ power supply modules is sufficient for the planned
installation (see section 3.3 S
)
Before beginning the installation tasks, always switch off the system.
Also, switch off all external voltages
Clean the MIQ module stack to remove the worst of any dirt before
taking it apart or opening it (see section 6.2 C
Before mounting the stack, check the contacts on the front and back
of any MIQ modules that were already in use somewhere else.
Clean any dirty contacts
After any change to the system, check the setting of the SN
terminator switches and adjust it if necessary (see section
3.9.1 T
).
Installing new
components
Install new components as described in section 3.5 C
. Then put the system into operation again
). Active modules are automatically
recognized by the controller and included in the corresponding module
lists.