wtw IQ SENSOR NET System 2020 XT, Operating Manual

Page: 73 / 216

System 2020 XT C
ONNECT
Installation
3 - 45
ba75970e01 10/2012
3.11 System extension and modification
3.11.1 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 auto
-
matically 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 con
-
tacts that may present a hazard of electric shock. Before opening the
MIQ modules, switch off the system and all external voltages that pres
-
ent a hazard of electric shock and secure the system against being in
-
advertently switched on again.
Installation instructions Note the following points in any system extension or modification:

Before any extension or modification, check that the planned num
-
ber of MIQ power supply modules is sufficient for the planned instal
-
lation (see section 3.3.1 S
YSTEM PLANNING
)

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 9.2 C
LEANING
)

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 termi
-
nator switches and adjust it if necessary (see section
3.10.1 T
OPOLOGY AND TERMINATOR SWITCH
).
Installing new
components
Install new components as described in section 3.5 C
ONNECTING SYS -
TEM COMPONENTS
. Then put the system into operation again (section
3.10 C
OMMISSIONING
). Active modules are automatically recognized by
the controller and included in the corresponding module lists.