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Siemens
TX-I/O™ Module system – Functions and operation
CM110561en_08
Building Technologies
Digital output functions
2018-10-25
Overview: behavior in case of a fault
Signal type TRA
Signal type
Response in the following
cases
– No address key
– Powerdown
– Masterdown,
integration via P-bus BIM
Response in the following case
– Masterdown,
direct island bus integration
Behavior when
fault has been
cleared
BO Relay NO 250V
BO Relay NC 250V
Q250
The relays are de-energized
*)
The behavior can be parameter-
ized: the relays are de-energized,
keep the last position, or take a
parameterized state.
Automatic
operation:
operation according
to process value
Tool override or
local override:
Operation in the
same state as
before the fault (the
commanded value is
saved in the module
BO Triac NO 250V
BO Triac NC 250V
--
The Triacs are de-energized The behavior can be parameter-
ized: the triacs are de-energized,
keep the last position, or take a
parameterized state.
BO Relay NO 250V
(Schrittschalter,
Stromstossrelais,
bistabiles Relais)
Q250
The relays are de-energized
*)
The switch status of the
power contactors is
maintained (step switch).
The behavior can be parameter-
ized, BUT:
Do NOT parameterize
"Keep" or "ON", as only pulses
are needed for step switches /
bistable relays
BO Bistable NO
BO Bistable NC
--
Behavior can be parameterized, see section 5.4
BO Pulse On-Off
Q250-P /
Q250A-P
The relays are de-energized
*)
The switch status of the
power contactors is
maintained (due to self-
latching or dual coil relay)
The behavior can NOT be
parameterized,
The relays are de-energized
MO Steps
Q-Mx
The relays are de-energized
*)
The switch status of the
power contactors is
maintained by means of self-
latching.
The behavior can be parameter-
ized: the relays are de-energized,
keep the last position, or take a
parameterized state.
MO Pulse
Q250-P1…P5 The relays are de-energized
*)
The switch status of the
power contactors is
maintained by means of self-
latching.
The behavior can be parameter-
ized: the relays are de-energized,
keep the last position, or take a
parameterized state.
AO 3-Pos Relay
AO 3-Pos Triac
Y250T
The actuator keeps its last
position.
The behavior can be parameter-
ized: the actuator goes to 0%,
keeps the last position, or goes to
a parameterized position.
BO PWM
--
The Triacs are de-energized The behavior can be parameter-
ized: the signal goes to 0 %,
keeps the last position, or takes a
parameterized state.
BO Blind Relay
--
The relays are de-energized The behavior can be parameter-
ized: all outputs are de-
energized, the last command is
completed, or the blind goes to a
parameterized position.
Additionally a time delay can be
set.
*) When using a normally-closed contact, a closed contact can be forced even if the
relay is de-energized.