8 universal analog inputs, 9 analog outputs – Horner APG XL7 OCS User Manual
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XL7 User Manual
The analog inputs have a digital filter that can be used to filter electrical noise that may be unavoidable
in some installations. The downside to digital filtering is the inputs will respond more slowly to sudden
changes in the actual input.
10.7.1 Common cause of analog input tranzorb failure, Models 2,3 & 4
If a 4-20mA circuit is initially wired with loop power but without a load, the analog input could see 24Vdc. This is
higher than the rating of the tranzorb.
This can be solved by not connecting loop power prior to load connection or by installing a low-cost PTC in series
between the load and the analog input.
Figure 10.7 – Analog input tranzorb - troubleshooting
10.8 Universal Analog Inputs
Note: See the data sheet for the XL7 OCS model being used for jumper settings and see the appropriate
) for details on how to use Cscape to configure the digital filtering.
The universal analog inputs provide a high resolution, very flexible interface for a variety of analog
inputs. These inputs include voltage, current, thermocouple, RTD and millivolt. Each channel can be
configured separately using jumpers and configuration settings in Cscape.
Like the standard analog inputs, these inputs have a digital filter that can be used to filter electrical noise
that may be unavoidable in some installations. The downside to digital filtering is the inputs will
respond more slowly to sudden changes in the actual input.
10.9 Analog Outputs
Note: Refer to the datasheet for XL7 OCS model being used for details on jumper settings.
The analog outputs on XL7 OCS devices provide high resolution voltage or current outputs. The voltage
or current selection is controlled with jumpers and configuration settings in Cscape. Note that each
channel can be separately configured for voltage or current mode.
When the controller is stopped the operation of each output is configurable. The outputs can hold the
state they were in before the controller stopped or they can go to a predetermined value. By default
analog outputs are set to a value of zero. For more information on Stop State, refer to the appropriate
) for the configuration chapter for Cscape settings.
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