93-520-20 Issue 3.3
Page 24 of 60
CirrusPro Engineer’s Manual
Inputs
Every CirrusPro has connections for four inputs. Each of these can be monitored as Normally Open
(default) or Normally Closed. Normally Closed is selected by checking the box adjacent to the Input
number. See Section 7 for input specification.
Inputs can be configured as one of the following:
Unused – The input is ignored
Isolate – Alarm relays are Isolated
Reset – Reset the sensor from any latched state
Disable – Shut down the CirrusPro
Fault – External Fault input that indicates as ‘External Fault’
Gain set – Uses all 4 inputs to set the gain of the unit. (Uses binary, Input 1 LSB, 0=Normal & >10=10)
Battery Fault – External Fault input that indicates as Battery Fault
Mains Fault – External Fault input that indicates as Mains Fault
S/R Disable – The Silence and Reset keys are disabled
Outputs
Four outputs are available within each unit. On scanning systems, there is a set of 4 per pipe. These
are non-monitored, volt free contacts. A scanning system is shown in the example, Pipe Selection is
not used for any other case.
The outputs will switch at the required alarm level. By default Output 1 to 4 are set to Pre-Fire, Alarm1,
Alarm2 and Alarm3 respectively.
By entering a Delay value greater than zero in the box,
the output is delayed, once the level has been reached,
for the specified time. The example shows a 30 second
delay before activating output 1 when the pre alarm
threshold has been reached.
Each of these outputs can be set as Normally Open
(default) or Normally Closed. Normally Closed is
selected by checking the box adjacent to the Input
number.
Selecting ‘Unused’ stops the output from activating.
3.2.13 Output Check
Selecting any option other than Normal simulates the selected level on
the pipe shown, when applied. Everything operates exactly as if this
threshold has been reached due to particle numbers.
Units will action lower levels in order until the set level is reached.
By returning the setting to Normal the unit will carry out a reset to clear
latched levels.
