Multi-Tech Systems 7600 User Manual
ION 7500 / ION 7600 User’s Guide
Configuring Digital Input
Digital and Analog I/O Technical Note
Page 217
Configuring Digital Input
Digital inputs are necessary for status monitoring or pulse counting applications.
Status monitoring can help you prevent equipment damage, improve
maintenance, or track security breaches. Some common status monitoring
applications are monitoring the closed/open positions of breakers, on/off status of
generators, armed/unarmed conditions in a building alarm system, and
over/under pressures of transformers.
Status monitoring can help you prevent equipment damage, improve
maintenance, or track security breaches. Some common status monitoring
applications are monitoring the closed/open positions of breakers, on/off status of
generators, armed/unarmed conditions in a building alarm system, and
over/under pressures of transformers.
N
OTE
If you want to confirm the status of a breaker, it should have an auxiliary circuit that indicates whether it
is open or closed. If you want to check for the over/under conditions of a transformer, you have to
interface the meter’s digital input to a transducer that monitors the transformer and turns on if such a
condition exists.
is open or closed. If you want to check for the over/under conditions of a transformer, you have to
interface the meter’s digital input to a transducer that monitors the transformer and turns on if such a
condition exists.
You can also have the digital inputs count transducer pulses to indicate, for
example, the number of times a breaker has tripped, or the number of rotations
completed by a device. Another option is to have the inputs read pulses from gas,
water, steam, or other electricity meters.
example, the number of times a breaker has tripped, or the number of rotations
completed by a device. Another option is to have the inputs read pulses from gas,
water, steam, or other electricity meters.
Digital Input Module
Digital inputs are used to monitor the status of a sensor such as limit, pressure or
temperature switches, and to monitor the status of loads. The source connected to
the Digital Input module provides a logic-level signal that describes the state of
device that is monitored. The device state is interpreted as either a complete pulse
or a KYZ transition (half of a pulse) and is made available as an output. Each state
change is determined by the amount of time (debounce time) that the external
signal remains in a state.
temperature switches, and to monitor the status of loads. The source connected to
the Digital Input module provides a logic-level signal that describes the state of
device that is monitored. The device state is interpreted as either a complete pulse
or a KYZ transition (half of a pulse) and is made available as an output. Each state
change is determined by the amount of time (debounce time) that the external
signal remains in a state.
Digital Input Module Setup Registers
Specifying a Debounce Time
The value specified for the Debounce setup register depends on the kind of signal
and the input devices being monitored. A typical value for solid state, dry contacts
is 0 to 5 milliseconds. For mechanical dry contacts, a value between 1 and 80
milliseconds is typical. Some input devices may already have a built-in debounce
time, often referred to as a Turn On or Turn Off time.
and the input devices being monitored. A typical value for solid state, dry contacts
is 0 to 5 milliseconds. For mechanical dry contacts, a value between 1 and 80
milliseconds is typical. Some input devices may already have a built-in debounce
time, often referred to as a Turn On or Turn Off time.
Setup Register
Description
Input Mode
Specifies if the external signal is pulse or KYZ
Event Log Mode
Specifies whether events are logged or not (LOG ON, LOG OFF)
Polarity
Determines if the signal from the hardware is inverting or non-inverting
Debounce
Specifies how long the external signal must remain in a state to be considered
a valid state change
Port
Defines which hardware port provides the signal