GE VersaPoint IC220PBI002, Руководство пользователя

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GFK-1911B Chapter 4 Installation 4-3
4
Planning Module Sequence in the I/O Station
The NIU is the first module in the station. The sequence of the other modules
should be planned carefully. Within a main circuit, place the I/O modules with the
highest current consumption (U
S
) first. For example:
▪
Discrete output modules with 8-slot housings
▪
Discrete output modules with 2-slot housings
▪
Discrete input modules with 8-slot housings
▪
Discrete input modules with 2-slot housings
▪
Special-function modules
▪
Analog modules
This approach is advantageous in that the high supply current does not flow
through the entire main circuit.
Locations for Analog Modules
High current flowing through voltage jumpers U
M
and U
S
increases the
temperature of the voltage jumpers and the inside of the module. Note the
following instructions to keep the current flowing through the voltage jumpers of
the analog modules as low as possible:
It is recommended that each analog module have a separate main circuit. If this is
not possible and it is necessary to use analog modules in a main circuit together
with other modules, place the analog modules at the end of the main circuit(to the
right of other modules).
This practice is particularly important for the thermocouple module IC220ALG630.
Internal module heating falsifies the temperature of the internal cold junction.
Therefore, position this module after all of the other modules to minimize the
current flowing through all voltage jumpers.