Owner manual

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Digital I/O Modules
Choose digital I/O modules when you need:
• Input Modules. An input module responds to an input
signal in the following manner:
- Input filtering limits the effect of voltage transients
caused by contact bounce and/or electrical noise.
If not filtered, voltage transients could produce
false data. All input modules use input filtering.
- Optical isolation shields logic circuits from possible
damage due to electrical transients.
- Logic circuits process the signal.
- An input LED turns on or off indicating the status
of the corresponding input device.
• Output Modules. An output module controls the
output signal in the following manner:
- Logic circuits determine the output status.
- An output LED indicates the status of the output
signal.
- Optical isolation separates module logic and bus
circuits from field power.
- The output driver turns the corresponding output
on or off.
• Surge Suppression. Most output modules have built-
in surge suppression to reduce the effects of high-
voltage transients. However, we recommend that you
use an additional suppression device if an output is
being used to control inductive devices, such as:
- Relays
- Motor starters
- Solenoids
- Motors
Additional suppression is especially important if your
inductive device is in series with, or parallel to, hard
contacts such as:
- Push buttons
- Selector switches
The digital I/O modules support:
 • Awidevarietyofvoltageinterfacecapabilities
 • Isolatedandnon-isolatedmoduletypes
 • Point-leveloutputfaultstates
 • Choiceofdirect-connectorrack-optimized  
communications
 • Field-sidediagnosticsonselectmodules
Connector types are indicated by the catalog number. For
example, the RPSSN8M12A has an M12 connector.
Digital DC Input Modules
RPSSN8M8A
RPSSN8M12A
RPSSN8M23A
RPSSP8M8A
RPSSP8M12A
RPSSP8M23A
Number of Inputs 8 Sinking 8 Sourcing
Keyswitch Position 1 1
Voltage, On-State
Input, Nom.
24VDC 24VDC
Voltage, On-State
Input, Min.
10VDC 10VDC
Voltage, On-State
Input, Max.
28.8VDC 28.8VDC
Input Delay Time,
ON to OFF
0.5 ms Hardware
+ (0…65 ms
selectable)*
0.5 ms Hardware
+ (0…65 ms
selectable)*
Current, On-State
Input, Min.
2 mA 2 mA
Current, On-State
Input, Max.
5 mA 5 mA
Current, Off-State
Input, Max.
1.5 mA 1.5 mA
PointBus Current
(mA)
75 75
Power Dissipation,
Max.
1.0 W @ 28.8VDC 1.0 W @ 28.8VDC
* Input ON-to-OFF delay time is the time from a valid input signal to recognition
by the module.
Digital DC Output Modules
RPSST8M8A
RPSST8M12A
RPSST8M23A
Number of Outputs 8 sourcing
Keyswitch Position 1
Voltage, On-State Output, Nom. 24VDC
Voltage, On-State Output, Min. 10VDC
Voltage, On-State Output, Max. 28.8VDC
Output Current Rating, Max.
3.0 A per module, 1.0 A
per channel
PointBus Current (mA) 75
Power Dissipation, Max. 1.2 W @ 28.8VDC
Serial Bus System