Churchill Nano Link IP67, Technical Manual, Page: 31 / 42

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8.2 Base-station Alarm Handling
As well as indicating fault conditions on the Heartbeat LED (as described in section 3.2), a
Nano_Link
base-station
also indicates them on digital outputs (if equipped). It does this by logically ANDing the digital inputs sent to it by the
remote base-station with the alarm flags. The outputs are thus as follows (digital state 1 = contact closed, 0 = contact
open):
Digital
Output
State Meaning Heartbeat LED
1
Outstation digital input 1 = 1
and
No comms alarm
Flashes continuously @ 4 flashes per second
1
0
Outstation digital input 1 = 0
or
Lost communication with outstation
If comms alarm:
Flashes 3 out of every 4
1
Outstation digital input 2 = 1
and
Outstation battery/mains supply is good
and
Base-station battery/mains supply is good
Flashes continuously @ 4 flashes per second
2
0
Outstation digital input 2 = 0
or
Outstation battery/mains supply is low
or
Base-station battery/mains supply is low
If battery/mains supply low:
If base-station low: Flashes 2 out of every 4
If outstation low: Flashes 1 out of every 4
1 Outstation digital input 3 = 1
3
0 Outstation digital input 3 = 0
1 Outstation digital input 4 = 1
4
0 Outstation digital input 4 = 0
All outputs can therefore be used to replicate the corresponding input at the remote end, with the proviso that outputs 1
and 2 will de-energise under fault conditions. (In the event of a comms failure, outputs 3 and 4 will hold their last valid
state).
If the user wants dedicated alarm outputs, he must insure that inputs 1 and/or 2 at the remote site are permanently
energised, so only digitals 3 and 4 are usable.