RDAC-XF AUX1 and AUX2 Input Behaviors

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Kroontje
Posts: 8
Joined: Wed Nov 18, 2020 11:34 pm

RDAC-XF AUX1 and AUX2 Input Behaviors

Post by Kroontje »

This post outlines the details germane to my question about RDAC-XF AUX1 and AUX2 input behaviors.

The setup:

iEFIS Discovery Lite connected to: 1) an RDAC-XF via CAN bus, 2) an iEFIS Extender via RS232.

NOTHING connected to the RDAC-XF except: 1) power, 2) GND, 3) iEFIS Discovery Lite via CAN bus.

BOTH AUX1 and AUX2 setup as follows:
Probe type: LM235 semiconductor
Highest Temp for display: 150
Alarm Temp: 135
Caution Temp: 130
Caution low temp: 70
Alarm low temp: 40 (box checked)
Lowest temp for display: 40
High alarm disabled
Low alarm enabled (box checked)

When AUX1 is pulled low by directly grounding the AUX1 input terminal, the iEFIS displays this flashing annunciation: "AUX1 HIGH, RDAC1".

When AUX2 is pulled low by directly grounding the AUX2 input terminal, the EFIS displays this flashing annunciation: "AUX2 High, RDAC1", followed by "TC/Temp 5, RDAC", then "TC/Temp 6, RDAC", then "TC/Temp 7, RDAC", and so-on stepping up sequentially through "TC/Temp 12, RDAC", whereupon the sequence begins again with "AUX2 High, RDAC1".

If the grounding of the AUX2 input terminal is interrupted during the TC "count-up", and then the grounding of the AUX2 input terminal is reestablished, the count-up begins where it left off during the previous grounding of the terminal.

If the iEFIS is powered down after the grounding of the AUX2 input terminal has been interrupted, when power is subsequently reapplied to the iEFIS, and the AUX2 input terminal is again grounded, the flashing, up-counting annunciation begins again with "AUX2 High, RDAC1", followed by TC/Temp 5, RDAC" and so-on again through TC/Temp 12.

Never does any iEFIS screen annunciation include TC/Temp 1 through TC/Temp 4.

Is this normal and expected, or is there an erroneous setting, or is there possibly a problem with the RDAC?

Observations of the EFIS System Diagnostics are unremarkable during testing.

My desire is to use AUX1 and AUX2 as gearbox chip detector annunciations. AUX1 appears to function perfectly for that role as currently set up; AUX2's "TC/Temp" annunciations appear to be spurious and, defeats my purpose.

Dave Kroontje
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