Installation guide

Glossary
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SELV safety extra low voltage. A secondary circuit designed and protected so that the
voltage between any two accessible parts (or between one accessible part and the
PE terminal for Class 1 equipment) does not exceed a specified value under normal
conditions or under single-fault conditions.
SIM subscriber identification module. Originally intended for authenticating users of
mobile communications, SIMs now have multiple applications. In Advantys STB,
configuration data created or modified with the Advantys configuration software can
be stored on a SIM and then written to the NIM’s Flash memory.
single-ended
inputs
An analog input design technique whereby a wire from each signal source is
connected to the data acquisition interface, and the difference between the signal
and ground is measured. Two conditions are imperative to the success of this design
technique—the signal source must be grounded, and the signal ground and data
acquisition interface ground (the PDM lead) must have the same potential.
sink load An output that, when turned on, receives DC current from its load.
size 1 base A mounting device, designed to seat an STB module, hang it on a DIN rail, and
connect it to the island bus. It is 13.9 mm wide and 128.25 mm high.
size 2 base A mounting device, designed to seat an STB module, hang it on a DIN rail, and
connect it to the island bus. It is 18.4 mm wide and 128.25 mm high.
size 3 base A mounting device, designed to seat an STB module, hang it on a DIN rail, and
connect it to the island bus. It is 28.1 mm wide and 128.25 mm high.
slice I/O An I/O module design that combines a small number of channels (usually between
two and six) in a small package. The idea is to allow a system developer to purchase
just the right amount of I/O and to be able to distribute it around the machine in an
efficient, mechatronics way.
SM_MPS state management_message periodic services. The applications and network
management services used for process control, data exchange, error reporting, and
device status notification on a Fipio network.
SNMP simple network management protocol. The UDP/IP standard protocol used to
manage nodes on an IP network.
snubber A circuit generally used to suppress inductive loads—it consists of a resistor in
series with a capacitor (in the case of an RC snubber) and/or a metal-oxide varistor
placed across the AC load.
source load A load with a current directed into its input; must be driven by a current source.