Detcon 10C Facilities - Manual (Page 8)

Model 10C
10C Control Module Instruction Manual Rev.0.0 Page 4 of 14
To silence an FM alarm relay, note that this is a separate configuration from the individual SSC alarm relay
configurations which may be individually set per SSC module.
An alarm relay output may be silenced if it is Silenceable and by following the Alarm Acknowledge or Alarm
Silence procedure described under the Alarm Acknowledge section that follows.
1.2.4 Alarm Reset
There is a Reset pushbutton on the FM front panel and there is also a signal input to the FM via the backplane
where an external switch can be connected. The switch should be a dry contact to Mod 10 DC common. When
the Reset pushbutton or the external reset signal is momentarily activated the FM accepts the reset to be
evaluated before turning off any latched alarms. For the case of a Reset being issued from the FM’s front panel
pushbutton, if any latching alarms are Latched, the front panel display will scroll the text: “Reset Alarms?” In
response to this query, the “ENT” pushbutton should be pressed to acknowledge the reset. In response to the
acknowledgement, the front panel display scrolls the text: “Reset DONE”. The latched relay does not turn
off unless the alarm condition reported from the SSC Slave has cleared.
The external reset does not have a displayed-acknowledge feature and when the FM senses that the external
reset signal is momentarily activated, the FM scrolls a text message on its front panel display: “Ext Alm Rst”.
.
Alarm Acknowledge (Silence)
Alarms that are configured as Silenceable may be silenced or acknowledged. That means that the relay output
on the FM for the alarm may be made to de-activate even though the alarm condition is still present. If an
alarm goes away and comes back, the relay will activate again. Acknowledgement only silences the relay
output for the duration until the alarm reappears.
There is a front panel pushbutton on the FM that is provided for two functions: one is that the pushbutton is the
Down Arrow button; the other function is to silence alarms. The button has a legend for the down arrow and
also with “SLNC”. When an alarm occurs, the “SLNC” pushbutton can be pressed, followed by the
acknowledging the “Silence Alarms?” scrolling display by pressing the “ENT” pushbutton.
1.3 Fault Circuit Functions
The FM Fault relay output is, as are the FM Alarm relay outputs, independent of the individual SSC relay
outputs. The FM Fault state is the Logical-OR of all the SSC modules being scanned, that is up to and
including slave Modbus address “Number of Slaves”.
The Fault state is the Logical-OR of the reported fault state from the SSC module and the Communications
Fault state of the same module. If the SSC module fails to communicate, the Communications Fault state
becomes true and the FM Fault will go true to indicate that an SSC module is not communicating. The FM
allows for a certain amount of communications message failures before setting the Communications Fault but
one good communications with the SSC module will reset the Communications Fault state.
The description of the cause of SSC Fault state (other than Communications Fault) is to be found in the 10C
instruction manual.
1.4 RS-485 Modbus to SSC Slaves
Reference Modbus Register assignments per 10B/10C
The 10C Modbus register definition defined per legacy of the 10B Modbus registers. The following table
defines the five 16-bit Modbus registers of data available, using function code 3. There are no other functions
or registers available on the Model 10 at this time of writing and for the purposes of this specification; this is
the sum of all Model 10 data available to the facilities module.