RTK Series UC625 Annunciator
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System Description and Features
General
The units can be manufactured in a range of sizes to suit individual applications. All units are designed
to be 4 alarm ways high but the number of windows wide is variable. This allows RTK to provide
systems suitable for 12, 16, 20, 24, 28, 32, 36 or 40 channels and all units are provided with two
additional channels used for monitoring the two integral supplies, Supply 1 and Supply 2
The annunciators are built up using variable size top / bottom plates, universal side plates to give a
basic panel mounting framework, a rear mounting motherboard and removable Legend Plate. The
universal Alarm Cards are of the plug in type and are easily accessed once the front legend plate has
been removed. The Alarm Cards simply plug into the motherboard, which also houses the terminals
for external connection by the customer. A removable legend plate is fitted over the front of the alarm
boards containing film legends, which identify the individual alarm channels.
Alarm Card
Each active Alarm Card controls four alarm points. The Alarm Card has an Application Specific
Integrated Circuit (ASIC), which controls the alarm ways. System control is arbitrarily allocated to one
of the ASIC's on any one of the Alarm Cards, obviating the need for a master control module. Each
Alarm Card is fitted with DIL switches, which are used to select the required features for each pair of
alarms.
Reliable Annunciation
The fact that all the cards are identical means that in the RTK Series UC625 alarm system there is no
master or controlling card, failure of which could jeopardise the whole system. System control is
arbitrarily allocated to any one of the alarm modules. Should this card be removed, damaged or fail for
any reason, another card will take over system control. This method of operation results in a system
with no single source of failure and multiple
redundancies giving the most reliable form of annunciation
possible.
Supply/Pushbutton/Relay Card (SPR)
This card is fitted in the right hand side of the annunciator and has 4 pushbuttons to cover all system
functions and two “power on” LED’s. The four pushbuttons are:- System Test, Acknowledge, Mute and
Reset. The two green LED’s are used to indicate "Power On" for Supply 1 (main) and Supply 2 (aux.).
Power Failure Monitoring
The SPR Card is fitted with two power failure alarms, which are used to monitor Supply 1 and Supply
2 and provide full alarm capability when either supply is not present on the unit.
The two supply inputs provide FULL redundancy of operation so that failure of a single supply input
will have no affect on the overall operation of the unit.
The standard version which uses an internally generated 24VDC Signal Supply to provide a feed to
the field contacts.
Powered input versions rely on the customer generated signal supply being available at all times.
The Power Failure alarm channels are fixed at alarm sequence ISA-M and are therefore controlled by
System Test, Acknowledge and Reset Pushbutton inputs to allow full control over the alarms.
In sub station applications it is common for a number of annunciators to share a common set of
controlling pushbuttons, the pushbutton inputs can therefore be connected between units as required.
