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Channels

When the channel is set for digital input, it monitors voltage or current. Note that the internal jumpers 
must match the software setting and must be set to Input, which is the default; see 

 to find out how to set the internal jumpers.

The Digital input channels allow you to configure the following options:

z

You can choose to remember the last state change, or latch, that occurred. Your options are to 
latch (remember) when the state changes from inactive to active or active to inactive.

z

You can choose to invert the signal, which is useful if your sensor is wired in such a way that 
closed is actually inactive, whereas closed is normally considered active.

z

You can also configure an alarm trigger and clear mode based on whether the Digital input is 
active or inactive, sending an email, syslog message, and/or SNMP trap when the alarm is 
triggered or cleared.

In an industrial freezer warehouse example, a D4 is used to monitor the open door sensor, so that 
every time a freezer door is opened, an alarm is triggered and a syslog message is sent to a syslog 
server, where the monitoring application notes the time.

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