Concept
Digital Inputs
The digital inputs can be used for sensing of multiple dry contact digital inputs in applications, such as equipment status monitoring or alarm point monitoring.
Danger
|
|---|
|
HAZARD OF ELECTRIC SHOCK, EXPLOSION, OR ARC FLASH Connect only devices with safe extra low voltage equipment (SELV/PELV) inputs/outputs to the AS-B server universal inputs/outputs and digital inputs. Failure to follow these instructions will result in death or serious injury. |
The AS-B server universal inputs/outputs and digital inputs are SELV/PELV. Connect only devices with safe extra low voltage equipment (SELV/PELV) inputs/outputs to the AS-B server universal inputs/outputs and digital inputs. Connecting devices that are not SELV/PELV poses an electrical hazard that will result in death or serious injury.
As counter inputs, digital inputs are commonly used in energy metering applications.
Inputs
The DI digital inputs are designed to read two different types of inputs:
Digital
Counter
Applied voltages beyond the absolute maximum ratings cause over current in the protection component D Z .
The external connection of a digital input is shown in the following figure:
K is the monitored external switch.
V S = 24 V
R PU = 10 kohm
A counter input uses the same hardware configuration as the digital input that is shown in the figure above.
Specifications
Channels, AS-B servers with 24 I/O points
|
4, DI1 to DI4
|
Channels, AS-B servers with 36 I/O points
|
0
|
Range
|
Dry contact switch closure or open collector/open drain, 24 VDC, typical wetting current 2.4 mA
|
Absolute maximum ratings
|
-0.5 to +24 VDC
|
| Digital inputs | |
Range
|
Dry contact switch closure or open collector/open drain, 24 VDC, typical wetting current 2.4 mA
|
Minimum pulse width
|
120 ms
|
| Counter inputs | |
Range
|
Dry contact switch closure or open collector/open drain, 24 VDC, typical wetting current 2.4 mA
|
Minimum pulse width
|
20 ms
|
Maximum frequency
|
25 Hz
|
AS-B Servers
AS-B Server Onboard I/O