NEX7250 Zone 2 Annunciator
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13.9 Supply Input/Output Module (Option SI/O)
The SI/O module is required in the following instances: -
1. In larger systems to distribute the 24VDC logic supply load evenly
2. To interlink multiple annunciator cabinets together to form larger systems
3. Where the pushbutton/programming module is fitted remote from the unit
This module is fitted within a standard cell but does not use a card slot so it does not affect the
number of alarm channels available.
13.10 RS485 Serial Communications (Option COM) Part No. CB6357POP1
All series 725 annunciators can be fitted with the optional serial communications card, which is
usually located in the cell directly above the pushbutton module. This card provides RS485 bi-
directional communication to and from third party devices using modbus ASCII or modbus RTU
protocols as standard. All pushbutton controls can be local to the annunciator or driven remotely via
the communications link. Up to 64 annunciators can be multi-dropped on the same communications
connection.
13.11 Individual Channel Repeat Relays Powered By The Field Contact
Voltage (Option RAV)
Option RAV is used in safety critical applications to power the individual channel repeat relays using
the field contact supply voltage. In this mode even if the annunciator logic supply is lost the repeat
relay facility will continue to function as normal. Please note:- The repeat relay can only function as a
signal follower when option RAV is used.
13.12 Three Horn Relay Outputs (Option 3HN)
Option 3HN provides three horn relays, (HNA, HNB, GPB), and one common alarm relay (GPA)
instead of two horn and two group relays. Channels are programmed to operate any of the relays
using function codes, F23 = HNA, F24 = HNB, F22 = GPB, (F21 = GPA).
13.13 Three Group Relay Outputs (Option 3GP)
Option 3GP provides three group relays, (GPA, GPB, HNB), and one horn relay (HNA) instead of the
two horn and two group relays. Channels are programmed to operate any of the relays using function
codes, F21 = GPA, F22 = GPB & F24 = HNB, (F23 = HNA).
Please note:- The HNB relay is not equipped with a reflash function.
13.14 Repeat Pushbutton Output (Option RPB)
Option RPB provides two independent volt-free contact outputs, which follow the operation of a
chosen pushbutton. A two channel relay card is added to the system and switches on the card are
used to set the function of each relay to follow either:- System test, lamp test, silence, ack, reset or
first reset.
