RTK NEX7250 User manual

NEX7250 Zone 2 Annunciator
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Warning
The NEX7250 System described herein operates on a logic voltage of 24VDC and as standard
24VDC is used for the field contact supply voltage. External power supplies using higher voltage
AC/DC primary sources and optional high voltage field contact voltages may be present if this is the
case please ensure the necessary precautions are taken.
REV DATED DESCRIPTION AUTHOR APPROVED
0 26/6/03 Original D.Adams T McLeman
1 29/05/07 Minor corrections D.Adams P.Cartmell
2 19/05/08 Updated to new Standards D.Adams T McLeman
3 05/01/10 Removed high risk impact warning D.Adams P.Hartley
NEX7250 Zone 2 Annunciator

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© RTK Instruments LTD 2008
The copyright in this work is vested in RTK Instruments Ltd and this document is issued for the
purpose only for which it is supplied. No licence is implied for the use of any patented feature. It must
not be reproduced in whole or in part, or used for tendering or manufacturing purposes except under
an agreement or with the consent in writing of RTK Instruments Ltd and then only on the condition
that this notice is included in any such reproduction. Information furnished is believed to be accurate
but no liability in respect of any use of it is accepted by RTK Instruments Ltd.

NEX7250 Zone 2 Annunciator
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Contents
1. I NTRODUCTION ......................................................................................................6
2. I NSTALLATION G UIDE .............................................................................................7
3. F RONT V IEW E XAMPLES ........................................................................................8
4. NEX7250 E NCLOSURE ..........................................................................................9
4.1 General..................................................................................................................................... 9
4.2 Panel mount ............................................................................................................................. 9
4.3 Wall Mount ............................................................................................................................. 10
4.4 Alarm connections.................................................................................................................. 10
4.5 Relay connections .................................................................................................................. 10
4.6 External power supply............................................................................................................ 11
4.7 Certification ............................................................................................................................ 11
4.8 Labelling ................................................................................................................................. 11
4.9 Documentation ....................................................................................................................... 12
5. P725 D ESCRIPTION AND F EATURES .....................................................................13
5.1 General................................................................................................................................... 13
5.2 Window Colours ..................................................................................................................... 13
5.3 Laser Printed Legends ........................................................................................................... 14
5.4 Adding Or Changing Film Legends ........................................................................................ 14
5.5 LED Illumination ..................................................................................................................... 14
5.6 Window Numbering System................................................................................................... 15
5.7 Alarm Card Types .................................................................................................................. 15
5.8 Pushbutton / Programming Module........................................................................................ 15
5.9 Pushbutton / Programming Module Options .......................................................................... 16
5.10 Fully Field Programmable .................................................................................................... 16
5.11 Sleep Mode .......................................................................................................................... 16
5.12 Automatic Mute Or Automatic Acknowledge........................................................................ 17
5.13 Integral Audible Alarm.......................................................................................................... 18
5.14 Remote Pushbutton Inputs................................................................................................... 19
5.15 Terminations......................................................................................................................... 20
5.16 Failsafe Mode....................................................................................................................... 20
6. I NPUTS ...............................................................................................................21
6.1 Optically Coupled Inputs ........................................................................................................ 21
6.2 Standard Input Configuration ................................................................................................. 21
6.3 Signal Supply Voltage ............................................................................................................ 21
6.4 Input Time Delay – Option AD* .............................................................................................. 22
6.5 Input Wiring Segregation........................................................................................................ 22
6.6 No Master Module.................................................................................................................. 22
7. O UTPUTS ............................................................................................................23
7.1 Common Outputs ................................................................................................................... 23
7.2 Critical Horn Relay - HNA ...................................................................................................... 24
7.3 Non-Critical Horn Relay - HNB............................................................................................... 24
7.4 Critical Group Relay - GPA .................................................................................................... 25
7.5 Critical Group Relay - GPB .................................................................................................... 25
7.6 Reflash Critical Group Relay - GPA ....................................................................................... 25
7.7 Reflash Non-Critical Group Relay - GPB ............................................................................... 25
7.8 Common Relay Function Codes ............................................................................................ 25
7.9 Multi-Function Relay Operating Modes.................................................................................. 25
8. T ECHNICAL SPECIFICATIONS .................................................................................26
8.1 General................................................................................................................................... 27
8.2 Fuse Details - SPR Module.................................................................................................... 27
8.3 Suitable Power Supplies ........................................................................................................ 27
8.4 P725 Annunciator Standard Versions .................................................................................... 27

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9. M ECHANICAL D ETAILS .........................................................................................28
9.1 Panel Mounting Clamps (panel mount version only) ............................................................. 28
10. A LARM S EQUENCES ..........................................................................................29
10.1 Summary .............................................................................................................................. 29
10.2 Audible Alarm Grouping ....................................................................................................... 29
10.3 Ringback Audible ................................................................................................................. 29
11. A DDITIONAL F EATURES .....................................................................................30
11.1 Automatic Reset ................................................................................................................... 30
11.2 Non-Latch Sequence (No Lock-In)....................................................................................... 30
11.3 Reflash Feature.................................................................................................................... 30
11.4 Ringback Sequence ............................................................................................................. 30
11.5 Two Pushbutton Operation .................................................................................................. 30
11.6 First-Up Sequences ............................................................................................................. 30
12. S EQUENCE C ONFIGURATION AND T ABLES ...........................................................31
12.1 ISA-Sequence M - Manual Reset......................................................................................... 31
12.2 ISA-Sequence A................................................................................................................... 32
12.3 ISA-A-4 Sequence ............................................................................................................... 33
12.4 ISA-R Sequence - ................................................................................................................ 34
12.5 ISA-F1A Sequence .............................................................................................................. 36
12.6 ISA-F2M-1 Sequence........................................................................................................... 37
12.7 ISA-F3A Sequence - ............................................................................................................ 39
13. O PTIONS ...........................................................................................................41
13. O PTIONS ...........................................................................................................41
13.1 General................................................................................................................................. 41
13.2 LED Assemblies (Option LED)............................................................................................. 41
13.3 Tropicalisation (Option TRO) ............................................................................................... 41
13.4 Individual Channel Repeat Relays (Option RLY)................................................................. 41
13.5 Individual Channel Dual Repeat Relays (Option RL2)......................................................... 42
13.6 Customer Specified Response Time (Option CRT**) .......................................................... 42
13.7 Adjustable Response Time (Option AD*)............................................................................. 42
13.8 Disable Integral Horn (Option DHN)..................................................................................... 42
13.9 Supply Input/Output Module (Option SI/O) .......................................................................... 43
13.10 RS485 Serial Communications (Option COM) Part No. CB6357POP1............................. 43
13.11 Individual Channel Repeat Relays Powered By The Field Contact Voltage (Option RAV)43
13.12 Three Horn Relay Outputs (Option 3HN)........................................................................... 43
13.13 Three Group Relay Outputs (Option 3GP)........................................................................ 43
13.14 Repeat Pushbutton Output (Option RPB) .......................................................................... 43
13.15 Group Relays Follow Inputs (Option GFI).......................................................................... 44
13.16 Additional Group Relay Contact (Options 2GA or 2GB) ................................................... 44
13.17 Total Group Relay (Option RTG) ....................................................................................... 44
13.18 SPR Module (Supply-Pushbuttons-Relay Module) ............................................................ 44
13.19 Logic Power Connections .................................................................................................. 44
13.20 Signal Supply Voltage Connections................................................................................... 44
14. NEX7250 C ONNECTION D ETAILS .......................................................................45
14.1 Typical Panel mount wiring .................................................................................................. 45
14.2 Typical Wall mount wiring .................................................................................................... 46
14.3 Cable Entry........................................................................................................................... 46
15. L ARGE W INDOW A LARM M ODULE WIRING ...........................................................47
15.1 Standard Unit Without Repeat Relay Facility....................................................................... 47
15.2 Optional Unit With Repeat Relay Facility ............................................................................. 47
15.3 Large Window Versions Fitted With An Odd Number Of Alarms......................................... 48
15.4 Standard Unit Without Repeat Relay Facility....................................................................... 48
15.5 Optional Unit With Repeat Relay Facility ............................................................................. 48
16. M EDIUM W INDOW A LARM M ODULE W IRING .........................................................49
16.1 Standard Version Without Repeat Relay Facility ................................................................. 49

NEX7250 Zone 2 Annunciator
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16.2 Optional Version With Repeat Relay Facility ....................................................................... 49
17. S MALL W INDOW A LARM M ODULE W IRING ...........................................................50
17.1 Standard Version Without Repeat Relay Facility ................................................................. 50
17.2 Optional Version With Repeat Relay Facility ....................................................................... 50
18. D UAL R EPEAT R ELAY O PTION ............................................................................51
18.1 Optional Version With Dual Repeat Relay Facility (Option RL2) ......................................... 51
19. S IGNAL S UPPLY V OLTAGE O PTIONS ...................................................................52
19.1 Standard Systems With Combined Logic And Signal Supply.............................................. 52
19.2 Standard Systems Using Externally Powered Inputs........................................................... 53
20. S YSTEMS F ITTED W ITH S ERIAL C OMM .’ S ............................................................54
20.1 Connections ......................................................................................................................... 54
21. S YSTEM C ONFIGURATIONS AND P ROGRAMMING ..................................................55
21.1 Programming Mode.............................................................................................................. 55
21.2 Changing A Function Setting ............................................................................................... 56
21.3 Programming Example......................................................................................................... 57
21.4 Checking Programmed Settings .......................................................................................... 57
21.5 Systems With Unarmed Ways ............................................................................................. 57
21.6 Points To Note When Programming .................................................................................... 57
22. F UNCTION N O K EY A ND D ESCRIPTIONS ..............................................................58
23. F UNCTION D ESCRIPTIONS ..................................................................................59
24. A LARM C ARD A DDRESS S ETTINGS .....................................................................65
24.1 Set Output Drive To Operate With LED ............................................................................... 65
24.2 Alarm Card DIL Switch SW1 Address Settings 0 To 40 ...................................................... 66
Alarm Card DIL Switch SW1 Address Settings 41 To 80 ............................................................ 67
Alarm Card DIL Switch SW1 Address Settings 81 To 120 .......................................................... 68
Alarm Card DIL Switch SW1 Address Settings 121 To 127 ........................................................ 69
25. A DJUSTABLE R ESPONSE T IMES .........................................................................70
26. S YSTEMS WITH S ERIAL COMMUNICATIONS ...........................................................71
27. S ERIAL C OMMUNICATION C ARD ..........................................................................73
28. S ERIAL C OMMUNICATION P ORT ..........................................................................75
29. S YSTEMS LINKED TO 3
RD
P ARTY D EVICES ............................................................79
30. P725 TO P725 S ERIAL L INKS ............................................................................80
31. C OMMISSIONING ................................................................................................81
32. M AINTENANCE ..................................................................................................82
32.1 No Special Tools .................................................................................................................. 82
32.2 Removing Filter Assemblies................................................................................................. 82
32.3 Changing Film Legend ......................................................................................................... 82
32.4 Changing LED Assemblies .................................................................................................. 82
32.5 Fuse Replacement ............................................................................................................... 82
32.6 Position Of Fuses On The Supply Card............................................................................... 82
33. S PARE P ARTS D ESCRIPTION ..............................................................................83
34. O THER RTK P RODUCTS ....................................................................................85
35. EC D ECLARATION OF C ONFORMITY ....................................................................86

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1. Introduction
The NEX7250 combines the RTK 725 Series Alarm Annunciator installed in an IP rated enclosure
and self certified to comply with the international standard IEC 60079-15. The unit is self certified to
Ex nA [nL] IIC T4, with an ambient temperature range of -20°C to +50°C. The IP rated enclosure is
available in two forms: A wall mount IP55 rated enclosure or a panel mount IP54 rated enclosure.
The annunciator is manufactured from universal cells, each 60 x 60mm, which can be assembled in
an array to provide the number of rows and columns required to suit individual panel designs.
Each cell within the annunciator is able to contain either: - ONE large, TWO medium or FOUR small
alarm windows, which can be illuminated by “fit and forget” LED assemblies.
The assembled unit is fully field programmable which allows the user to enable a number of pre-
defined features to control the operation of the annunciator with regards to alarm sequence, horn
groups, common alarm groups or optional Modbus communications.
Selection of features is on a per channel basis with no special tools or programming knowledge
required. All programming is carried out from the front of the unit using the integral pushbutton /
programming module, which allows changes to be easily made during commissioning or at a later
date after the equipment has been installed.
Large and medium window version alarm cards are fully interchangeable within the annunciator, on
small window versions an additional card type is used for the 2
nd
pair of alarm channels but cards of
the same type remain fully interchangeable.
Reliability of operation is increased over conventional annunciators as each alarm card is fitted with
its own application specific integrated circuit (ASIC), which is capable of complete system control.
During initial power up one of the alarm cards will automatically act as a master controller with
regards to flash rates etc and in the event that this card fails or is removed another card will
automatically take over the role of master controller.
The standard unit is supplied with five integrally mounted common output relays, which are used to
provide 2 horn relay outputs, 2 group relay outputs and a multifunction relay output with
programmable function.
Additional options exist for more complex requirements including integrally mounted signal
duplicating relays on a per channel basis, bi-directional RS485 serial communications link and user
selectable time delays on each channel.
Accessibility for normal maintenance, LED changes, legend/filter changes and programming is
accomplished from the front of the panel without the use of special tools.

NEX7250 Zone 2 Annunciator
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2. Installation Guide
This product has been certified to be mounted in a zone 2 (equipment category 3) hazardous area.
Equipment must be installed in accordance to IEC60079-14 (Electrical installation in hazardous
areas).
There are various requirements that need to be met in order for this equipment to be used safely.
These requirements are as follows:
1. The IP rating of the enclosure should not be compromised when mounted or when inserting
the cable glands
2. All external earthing should use 4mm cable as a minimum
3. Any fuses used will be marked with a label giving type and rating. Fuses should not be
replaced with the power connected as this may cause sparks, which could potentially cause
explosions.
4. All Relays are energy limited and are pre-wired to energy limited terminals. Any connections
to these terminals must meet the safety parameters specified in the product certificate
These are shown below:
Ui=24V, Ii = 45mA, Pi = 1.3W, Ci = 0, Ii = 0
5. Any external equipment connected outside the enclosure but still within the Zone 2 area
must meet IEC60079-0 requirements.

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3. Front View Examples
SIX
WINDOW
COLOURS
AVAILABLE
BATTERY
LOW
VOLTS
LEVEL
TRANS
FAILURE
SMALL
WINDOW
VERSION
30 X 30 MM
NO 2
AIR COOLER
FAILURE
NO 1
AIR COOLER
FAILURE
LAMP
OR
LED
VERSIONS
SIX
LED
COLOURS
AVAILABLE
PROTECTION
TRIP
FULLY
FIELD
PROGR
MOTOR 1
HIGH
TEMP
LASER
PRINTED
FILM
LEGENDS
OPTIONAL
SERIAL
INTERFACE
CARD
MOTOR 2
HIGH
TEMP
LAMP
TEST
PLC
FAILURE
GAS
PRESSURE
LOW
Small Window Version
SIX
WINDOW
COLOURS
MEDIUM
WINDOW
VERSION
30 X 60 MM
LAMP OR LED
ILLUMINATION
LARGE
WINDOW
VERSION
60 X 60 MM
LAMP OR LED
ILLUMINATION
SIX
WINDOW
COLOURS
SIX
LED
COLOURS
LASER
PRINTED
FILM
LEGENDS
OPTIONAL
SERIAL
INTERFACE
CARD
Medium Window Version Large Window Version

NEX7250 Zone 2 Annunciator
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4. NEX7250 Enclosure
4.1 General
The NEX Systems are manufactured to meet individual customer's requirements as long as they are
within the maximum parameters of equipment certificate.
4.2 Panel mount
The panel mount version consists of an IP54 rated stainless steel door with a Perspex viewing
window, the 725 unit is then mounted in an IP54 rated box which is mounted in the viewing window.
The size of this enclosure is depended on the cell size of the annunciator, as long as the box doesn’t
exceed the maximum size stated on the certificate.
Layout of panel mount box
This type of NEX7250 allows the user to connect external pushbuttons which can then be mounted in
a suitable control panel. If this panel is situated in the Zone 2 area, zone 2 certified pushbuttons
must be used. The customer may also incorporate a Zone 2 isolator into the enclosure to allow then
to drive an external I.S horn.
12
11
16
15
6
5
4
2
3
1
10
9
814
137
20
19
TEST RESET
MUTE
POWER
ACK
LAMP
TEST
SYST
RESET
FIRST
18
17
22
21
CERT' LABEL

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4.3 Wall Mount
The wall mount version consists of an IP65 rated box with an IP65 rated viewing window. The 725
unit is then mounted in an IP54 rated box which is mounted in the viewing window. The enclosures
used are manufactured externally so the size of the unit is dependent of the sizes available from the
manufacturer. The wall mount version has the external pushbuttons mounted on the enclosure and
also gives the option for audible and visual devices to be mounted to the enclosure. It is also
possible to mount the customer power supply within the enclosure.
Layout of Wall mount box
4.4 Alarm connections
Due to the type of application the NEX7250 is used in the user may connect their alarms from any
zone. If these alarms are associated with a hazardous area suitable protection must be used.
For connections to a safe area it is recommended fused terminals are used, either in the enclosure or
from the area in which they are coming from.
If fused terminals are used the correct type and value and type of fuse shall be shown on a label next
to the fuse holder. A warning label will also be present stating DO NOT REMOVE FUSE WHEN
ENERGISED.
4.5 Relay connections
Because of the certification type used for the NEX7250 all relays within the 725 must via suitable
energy limited terminals, this includes both group and repeat relays.
BEACON
PUSHBUTTONS
4
3
2
8 12
7
6
11
10
1 5 9
AUDIBLE
16
15
14
LAMP
20 TEST
SYST
TEST
19
18 22
13 17 21
RESET
ACK
POWER
MUTE RESET
FIRST