unD4I / unD4I-L
User Manual
Attero Tech LLC 2015
Page 12
614-00020-06
2.5 – Logic Outputs (unD4I-L only)
The logic outputs can be used to drive external indicators or devices. The outputs can be driven directly from a 3
rd
party control system or can be linked to the digital state of one of the unD4I-L inputs. The logic inputs feature two
operational modes that can be configured based upon the physical configuration of the logic output interface.
2.5.1 – Sink Mode
The logic outputs can be used to indicate the logic state in a sink mode configuration. This mode is optimized for driving
moderately heavy loads such as relay coils. In this mode, the outputs can sink up to 50mA from a 5V to 24V power
supply.
When the logic outputs are wired in this mode, the logic outputs will work as active-low outputs when integrated with the
3rd party control protocol or the unIFY Control Panel software.
Figure 11 - Sink Mode Examples
*Note
: If used with an inductive load such as a relay, an external freewheeling diode must be placed across the logic
output and the supply connection. Use a 1N4004 or similar diode for this application
.
The unD4I-L has an in-built, current limited 24V DC supply connection available on the rear panel terminal block. This
supply connection is not intended to be used to supply power to other devices. Additionally, the use of an external
supply is also supported.
2.5.2 – Source Mode
In the source mode configuration, the logic outputs can be used to source 3V at up to 10mA for direct connection to LEDs
or other logic devices. If a larger voltage or current is needed, wire the outputs in the sink mode configuration as
described in the next section.
Figure 12 - Source Mode Example
When the logic outputs are wired in this mode, the logic outputs will work as active-high outputs when integrated with
the 3rd party control protocol or the unIFY Control Panel software.