July 2013 © British Telecommunications plc 2013
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Figure 12 - connecting a relay module to CTRL output 2. Note that the outputs sink
current when low
Output 3
Output 3 acts as a “Return Path Signalling” (RPS) output.
The output is normally low, but will rise high when input pin 4 is triggered. It will return low
when an acknowledge signal is returned from the BT Redcare server (ESP). The output has a
minimum operation time of 1s. When the acknowledgement is received in less than 1 second
after pin 4 is triggered then the output will remain high for 1s.
This output can be inverted through the web console if required.