GDS Combi User manual

Combi
OPERATING
HANDBOOK
TECHNOLOGIES LTD
C925
Manual No.194D1C
Issue P.v2
www.gds-technologies.co.uk
Tel. [phone] Fax. [phone]
Email. [email protected]

1
N.B: (#) is the System menu option number
This document is non contractual and the equipment specification and detail may be modified at any time without prior notice.
Contents
Page
Contents ..........................................................................................................................................................................................1
System Overview ................................................................................................................................................................2
General Specification ..........................................................................................................................................................4
LED and LCD Indicators......................................................................................................................................................5
Buttons and Lockout............................................................................................................................................................7
Entering a password to get to User or Engineer mode ......................................................................................................8
• Default Passwords ........................................................................................................................................................8
• COMBI System Menu Index (see appendix #1 for brief description) ..........................................................................8
Direct and Addressable Line text ........................................................................................................................................9
Holding the Display..............................................................................................................................................................9
Testing the LEDs (7) and Relays (8) ................................................................................................................................10
Inhibiting a sensor (14)......................................................................................................................................................10
Changing the direct gas type (18) ....................................................................................................................................10
Gas Type Library ..............................................................................................................................................................11
Event to remote relay (23) ................................................................................................................................................12
Dimming the LEDs (11) ....................................................................................................................................................12
Mute the buzzer ................................................................................................................................................................12
Local and Remote relays ..................................................................................................................................................13
Modbus set up and indicators ..........................................................................................................................................13
Set Up Network ................................................................................................................................................................14
RS232 data log output ......................................................................................................................................................15
Event log (9) ......................................................................................................................................................................15
Data to and from a PC using Hyper-terminal ....................................................................................................................16
Real Time Clock ................................................................................................................................................................17
Refresh Rate ....................................................................................................................................................................17
Changing ‘Engineers’ Password........................................................................................................................................18
Calibrating Gas Sensors
• 16 direct 4-20mA gas sensors ....................................................................................................................................18
• 64 Addressable gas sensors ......................................................................................................................................18
• Cell replacement on Combi sensors - sensor calibration............................................................................................19
Setting the Time to Alarm ..................................................................................................................................................19
Setting Alarm Levels..........................................................................................................................................................19
Setting number of Decimal Places ....................................................................................................................................19
Setting the 4~20mA Deadband ........................................................................................................................................19
Alarm Relay off timers ......................................................................................................................................................20
Voting Relays ....................................................................................................................................................................20
Time Weighted Alarms ......................................................................................................................................................20
Defaulting Sections of the Panel ......................................................................................................................................21
Default the Whole Panel from Power Up ..........................................................................................................................21
Repeater (on CAN2 only) ..................................................................................................................................................21
Installation ........................................................................................................................................................................22
• Siting the Sensors
• Sensor Cable Routing ................................................................................................................................................24
• Equipment Installation Guides ....................................................................................................................................25
• Service – Routine Attention ........................................................................................................................................28
• Daily ............................................................................................................................................................................28
• Twice-yearly Maintenance Schedule ..........................................................................................................................28
• Action to be taken if the alarm activates ....................................................................................................................28
Appendix 1 (System Menu by number) ..........................................................................................................................29
Appendix 2 (Image of typical PC-Panel-PC text file) ......................................................................................................35
Appendix 3 (Modbus Register Specification for COMBI 16 channel + CAN system) ....................................................37
Appendix 4 (Event numbers) ..........................................................................................................................................37
Appendix 5 (Fuse Detials) ..............................................................................................................................................38
Fig. 1 (PC adapter (converts sensor data output to RS232 for PC System Configuration) ..........................................38
Fig. 2 (System Configuration & Mainboard to sensor wiring Diagram) ..........................................................................39
Fig. 3 (Combi Controller Network Configuration)……………………. ..............................................................................40
Fig. 4 (Combi Circuit Boards)..........................................................................................................................................41
Fig. 5 (System Wiring) ....................................................................................................................................................42
Fig. 6 (Enclosure Detail)..................................................................................................................................................42
Set up procedure for Flammable sensors (C893) .......................................................................................................….43
Set up procedure for Toxic sensors (C894) .................................................................................................................….45
Auxillary Equipment
Relay Switch Set-up C1179 ..............................................................................................................................................47
Channel 4~20mA C1147 ..................................................................................................................................................48
4~20mA Input C1180 ........................................................................................................................................................49
Combi Sensor - location / Gas type - Log ...................................................................................................................….50

System Overview
The COMBI is a 16 direct (4-20mA) plus 64 addressable channel gas monitoring system
which displays gas concentration and constantly checks for alarm conditions.
Each channel consists of a remote gas sensor located at the point where gas is to be
measured. The direct sensor types are individually wired back to the COMBI where as the
addressable sensors can be connected to a shared CAN bus network minimizing cable
requirements.
Each channel when connected becomes active and is recognized by the system and a
fault occurs if it becomes disconnected. This allows a system to be activated on an
individual sensor basis as commissioning takes place.
The gas types and alarm levels for Direct channels are set at the Combi panel but
addressable types transmit this information to the panel. However, alarm levels for
addressable sensors can be altered at the Combi panel or at the sensor itself.
Alarms can be individually set to be latched (requires reset button to clear) or unlatched
(self clearing).
The panel can be powered from mains or 24V dc input with battery backup terminals.
An output 24V 250mA terminal is available to power user devices.The battery input and
mains voltage is monitored and will create a fault if the voltage is too low but the user has
the option to disable these faults.
The Combi panel controls most actions and its dimmable backlit LCD display is capable
of indicating the state of gas measurements or fault conditions. Likewise, dimmable LED’s
internal and external give additional status information.
Many parameters including a text description of the location of a sensor are
programmable via user and engineer’s menus and retained when power is off. These
parameters are reloaded at the next power up so that the system will perform as it did
previously. The Combi panel also has two RS485 Modbus channels and can send data
when requested to do so to a Modbus master controller thus allowing independent system
management facilities.
Engineering menus allow for diagnostic monitoring of the Modbus transmit and receive
buffers. A remote repeater can also be connected which allows the LCD, LED’s and
buttons to be located elsewhere on a CAN bus as well as remaining functional on the
main panel. A network controller can also be connected which appears as a repeater but
to multiple panels connected to the CAN bus. A real time clock keeps track of time and
this time value is displayed on the LCD and appended to any panel events such as
alarms or faults etc. These events are retained in a 99 event memory which can be
viewed on the LCD or sent to a PC via the RS232 channel. Likewise this RS232 channel
can accept setup parameters from a PC and if needed can send the Combi parameters to
the PC as a simple text file which can be edited. Text is sent out via the RS232 channel
as an additional data logging facility. Events and gas level changes are the main types of
data presented which the user can capture using HyperTerminal (or similar) on a PC.
The current time is transmitted via the CAN bus and any addressable sensor will receive
it. Those addressable sensors with a local LCD display will show this time in addition to
the gas concentration data etc.
- If multiple panels are connected on CAN bus, then the panel with the lowest address
will send the time to the other panels.
2

3
Sensors connected on the CAN bus can have their address changed using ENGINEER’S
menu 27 (Described in appendix:1).
Please note:
Connected sensors are recorded as present by the panel.
If a sensor is removed, and then the panel is switched on, a fault will occur showing the
missing sensor.
Use ENGINEER’S menu 16 to clear all addresses if required.
Button action on the Combi panel can be protected by a Key lockout connection to
prevent misuse. However, muting the buzzer which sounds if an event occurs can still be
silenced by pressing the ACCEPT button (1).
On board relays with voltage free contacts indicate alarm and fault states and additionally
these relays are used for voting whereby sensors can be grouped and the relay is
activated when a number of sensors have gone into alarm. The last four relays labeled
OPT5, 6, 7 and 8 can also be used for time weighted average alarms covering the
requirements of 15 minute and 8 hour measurements. Additionally, all 8 onboard relays
and the first 16 of the external relays have a programmable delay to de-energise
parameter which for example allows for fan evacuation of a space containing detected
gas. These relays and the first 16 relays on the remote relay board can be set to be
normally energised or de-energised.
Front panel LED’s indicate the general state of the panel. The red alarm LED will flash for
new alarms until accepted/muted when it stays on constantly until reset. The amber fault
LED comes on if a fault is present. If any sensor channel is inhibited the amber inhibit
LED will be on.
Additional reset and mute terminals are available to allow remote action in the event of an
alarm or fault condition. Test facilities are included in the engineer’s menu, which allow
these relays to be manually activated during commissioning.

4
General Specification
Direct 4-20mA sensors 16 Sensor Inputs (maximum) - source
2 Wire sensor Power = 0.6W
3 Wire sensor Power = 1.7W
Addressable sensors 64 Sensor inputs (maximum) (CAN network – 4 wire)
end of line termination required. 1.7W per sensor
Internal Sensor Supply 24V.DC – 3A / 70W
(Loading) Systems exceeding 70W sensor load should be powered from an external
24V power source. (See auxiliary power pack [260W]
Price code: 200-003)
Sensor types Electrochemical - Infra Red - Pellister
Sensor cable Addressable CAN bus, 4 Core 1.5mm screened
Direct 2/3 core 0.5mm screened
Power supply 230/115Vac 50/60Hz +/-15%
24-28Vdc or Battery (external charger)
Power Board = 6 Watts
Main processor board = 5 Watts
(See 1 and 2 for sensor loading)
Indication 4 line, 40 character LCD
3x Externally visible LEDs for ‘Fault’, ‘Alarm’ and ‘Sensor Inhibit’
PCB LED’s include: ‘DC Fail’, ‘AC Fail’, ‘Sensor Fail’, ‘CAN Fail’, ‘Modbus Fail’,
‘Watchdog’, ‘System Inhibit’, ‘O/R’, ‘Hi Alarm’, CAN1/2, RS232, and
‘24V’/’12V’/’5V’ rails
User Interface 7 Buttons on main board and or repeater
(Up, Down, -, +, Select, Dim, Reset)
Alarm settings 3 Alarm levels which are user selectable High, Low, and Over range
Combi Panel Outputs RS232 data log, (up to 10 meter) CAN bus (up to 1Km)
Modbus slave to an external Modbus Master (up to1Km @ 9600 baud)
Optional Relay card (up to an additional 64 relays)
Common Low alarm relay DPCO or ‘Group 1’
Common High alarm relay DPCO or ‘Group 2’
Common Over Range alarm relay SPCO or ‘Group 3’
Fault relay SPCO or ‘Group 4’
OPT G5 LTEL/STEL relay SPCO or ‘Group 5’
OPT G6 LTEL/STEL relay SPCO or ‘Group 6’
OPT G7 LTEL/STEL relay SPCO or ‘Group 7’
OPT G8 LTEL/STEL relay SPCO or ‘Group 8’
Sounder relay SPCO
(Relays Lo, Hi and OR can be latched or unlatched)
(Groups and LTEL/STEL relays can only be unlatched)
Relay rating 5A@250Vac none inductive / capacitive
Audible Mutable Buzzer on both Motherboard and Front panel
Remote sounder (optional)
Dimensions (H) 265mm x (W) 315mm x (D) 100mm
IP rating IP52 optional IP65
Enclosure Mild steel powder coat BS00A01
IP52 (optional IP65)
Cable entry Bottom / Rear 20mm push-outs
Weight 5Kg
Terminals Field terminals 2.5mm
Operating temperature 5 to 40˚C
Features Remote reset Keylock
Remote repeater panel (option)
operating distance 1km
16way 4-20mA catalytic converter panel (option)
Multiple panels using the network controller (option)
32 way CAN relay panel (option)

5
LED and LCD indicators
A four line 40 character LCD displays a range of information typically shown below.
Line 1 Standard 4~20mA sensor, values and gas type and location
Line 2 Addressable sensor, values and gas type and location
Line 3 General information, Number of Alarms, Faults and Connected sensors
E.g. D=4 means 4 direct sensors connected
E.g. A=6 means 6 addressable sensors connected
Line 4 Date and Time alternating with user text.
The top line displays the direct 4~20 inputs indicated by D. This will cycle through all
active sensors automatically but will hold on a specific sensor if it is in alarm.
Pressing +button (4) will stop the cycle on the current sensor for 999 seconds.
If a new alarm occurs, the display will show this sensor.
The type of gas and the text associated with this sensor is displayed.
To restart the cycle press the –button (2) or RESET (7)
The second line displays addressable inputs indicated by A. this will cycle through all
active addressable (CAN) sensors automatically but will hold on a specific sensor if it is in
alarm. Pressing + button (4) will stop the cycle on the current sensor for 999 seconds.
If a new alarm occurs, the display will show this sensor.
The type of gas and the text associated with this sensor is displayed.
The third line displays the number of alarms and faults present in the Combi system.
Normally these are zero. Additionally, the number of 4-20 and Addressable sensors in the
system are displayed.
The fourth line displays shows the internal clock reading together with the day and
date. All internal events use this clock to record the time of event.
If an alarm or fault event occurs, the clock display is substituted with the text for this
event and will alternate every second or so if the text is lengthy but will remain readable.
This text which describes the event (e.g. Modbus fail) is also the same text which is
stored in the event log which can be viewed separately. (see Event Log).
This line also alternates with user text, eg company name and telephone number.
Direct
sensor
Gas Value
D4 20 %LEL xxxxxxxx xxxxxxxxxxx
A6 10 PPM CP xxxxxxxx xxxxxxxxxxx
Alarms = 0 Faults = 0 Sensors D = 4 A = 6
12.24 Tue 31 Jul 2012 GDS Technologies Ltd 0113 2860166
Gas Type Customer Programmable text
Addressable
sensor
}
Continuously
updating
display lines
alternating user text
display (programmable)

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The LEDs local to the panel are as follows:
Alarm Internal/ Colour Description
External
Or Alarm I Red on if any sensor currently has an over range alarm
Lo Alarm I Red on if any sensor currently has a low alarm
Hi Alarm I Red on if any sensor currently has a high alarm
DC fail I Amber on if battery is low
AC fail I Amber on if mains has failed
Sensor fail I Amber on if any sensor has failed
CAN fail I Amber on if any addressable sensor has stopped communicating
Modbus fail I Amber on if the Modbus master has stopped communicating
System Inhibit I Amber on if the system is not checking alarms
Sensor Inhibit X Amber on if any sensor has been inhibited
Watchdog I Amber on if the processor has had a watchdog reset
Power I Green on if power applied
Fault X on if a fault exists
Alarm X on if alarm exists
(I = view internal X = view external)
If the fault or alarm LED is flashing, this indicates a new event and when accepted by
pressing the UP (1) button it remains on (not flashing).

7
Buttons and Lockout
7 user buttons are provided on the front to allow control and setting up of the Combi
system plus there is an internal PCB button. These buttons are also numbered and
shown in brackets. e.g. button 3 is (3).
Button 1 is the Accept/Mute and UP button. When in engineer’s mode, it is used to
increment parameters which are being modified. Also, it allows the displayed sensor to be
moved onto the next active sensor.
Button 2 is the “-” button. Used when decrementing items in engineer’s menu, also to
escape from the engineers menu system when not in any specific menu.
Button 3 is the SELECT button. It is used to enter and exit many of the engineer’s menus.
Also when first pressed, it prompts the entry of an engineer’s password. When correct, the
engineer’s menu is displayed in which sub-menus can be selected by pressing the
SELECT (3) button again.
Button 4 is the “+” button. Pressing this allows the display to hold the automatic sequence
of sensors being displayed for 999 seconds.
When in engineer’s mode, it is used to increment parameters which are being modified.
Button 5 is the DOWN button. Used when decrementing items in the engineer’s menu.
Button 6 is the DIM button. It is used for dimming the LED’s and LCD backlight and will
toggle between full brightness and the dim level previously set in the engineer’s menu. DIM
can be used at any time except when doing an LED test whereby automatic dimming occurs
to reduce current.
Button 7 is the panel RESET and is used to clear faults or alarms. It is generally active and
will act regardless of entry of passwords.
To prevent unauthorised use of the buttons, Key lock input is provided on the main
processor PCB, and the buttons are locked out of use when this terminal is connected to 0V
(adjacent terminal) Even when locked, the buzzer can still be muted by pressing the
ACCEPT button (1).
Processor reset button and a flash programming jumper are situated directly on the PCB
and are not accessible from the front panel.
This button when pressed will restart the processor as if just powered up and should only be
used in the event of a system crash. The jumper should be removed for normal operation.

Entering a password to get to User or Engineer’s menus
To protect system parameters from being altered by unauthorised people. Two passwords
have to be entered to gain access to available menus which allow changes to be made.
The first 4 button password is the USER menu and gives access to a limited set of menus,
E.g. clock set, LED test etc. The second 4 button password is for the ENGINEER’S menu
which gives access to all menus including the users. A sequence of 4 buttons is accepted as
the entry for a password.
To start the entry of the password, press SELECT (3).
The password display is shown on the LCD and each of the 4 buttons in sequence can now
be pressed.
Default Passwords
The USER password is defaulted to DOWN (5) pressed 4 times.
The ENGINEERʼS password is defaulted to + (4) pressed 4 times. (or as per customer
requirement)
Changing the engineers password is described later.
The user password cannot be changed.
Combi System Menu Index See Appendix 1 for further details.
Note: User menu only contains items shown in red. Engineer's menu contains all items.
1 View Modbus Reg
2 Set Clock
3 Inhibit all Sensors
4 View Modbus txrx
5 Refresh Rate
6 Edit Company Text
7 Lamp Test
8 Relay Test
9 Event Log to LCD
10 Add zero/span
11 LCD Led Bright
12 Exit
13 Top of Engineers
14 Inhibit Sensor
15 Add Alarm Levels
16 Clear All Addresses
17 Alter Chan Text
18 Alter Gas Type and Range
19 View Add sensor status
20 4-20mA Zero Span
21 4-20mA Alarm Levels
22 Unlatched Alarms
23 Event to Relay64
24 Relay off Timers
25 Channel Voting
26 Seconds to Alarm
27 Setup Network
28 Event log to PC
29 Data PC to Panel
30 Data Panel to PC
31 Ltel Stel Alarm
32 Default Sections
33 Engineer Password
34 Set Modbus Baud
35 Set Power Alarms
35 Set Power Alarm
36 Energised Relays 8

9
Direct and Addressable Line text
The Combi system measures data on all active sensors.
Direct sensors are done sequentially but addressable sensors send their data periodically
when available (every few seconds).
Each sensor has a text description (stored on the main pcb, not in the sensor) which
describes physically where it is in the system and this text appears on the LCD as the
most recent measurement is displayed. Using the engineer’s menu, this text can be
altered from the default text to something more meaningful.
Editing this text is either manual using buttons and the LCD or by sending a text file from
the PC. The latter is much faster and is preferred. The manual mode is activated from
ENGINEER’S menu 17 which presents the direct 4-20 channels text first followed by the
Addressable text.
Pressing + (4) or – (2) changes which channel is to be altered and pressing UP (1) enters
the text editing mode for this channel. The + (4) and – (2) buttons now move a cursor
under the text and UP (1) and DOWN (5) alter the character at this cursor position. When
editing is finished for this channel, press SELECT (3) to exit the editing which returns to
allow changes on another channel by pressing the UP (1) button again. Alternately
pressing SELECT (3) will exit the direct 4-20 channel text and enter the Addressable
channel text selection. Again the buttons are used in exactly the same way to change the
text description for networked Addressable sensors.
SELECT (3) when pressed will exit the manual mode and save the text changes in non
volatile memory on the main PCB and return to the ENGINEER’S menu.
See also DATA to and from a PC using Hyper-terminal which allows a much quicker
method of editing using a PC.
Holding the Display
As the display cycles through the active sensors sequentially, it may be required to stop
on a particular channel for maintenance.
This can be achieved using the + (4) button on the front panel which when pressed will
hold the current sample for 999 seconds. A countdown is displayed on the LCD showing
that hold is in progress. At the end of this time normal display sequencing will resume.
The gas values displayed on the LCD during hold are still the current live readings from
the sensors.
Hold can be removed at any time by pressing the + (4) button for a second time.
As the sequence of display continues it is sometimes required for maintenance to choose
another sensor for display and this can be achieved using UP (1).
This button when pressed terminates the current display it moves to the next displayed
channel and if pressed continuously, this button will step through all available sensors
When the desired channel is reached and the button released, press + (4) to hold this
display for 999 seconds. Pressing + (4) will release the system back to normal.

10
Testing the LEDs (7) and Relays (8)
To test all LED’s and beep the buzzer, use menu number 7 and press SELECT (3) to make all
LED’s illuminate in dimmed mode to see if they are functioning. At the end of the test, the
buzzer beeps twice to confirm its operation.
Note: some diagnostic LED’s on the main PCB are not part of this test. In particular these are,
Modbus, RS232 and CAN active. These LED’s are only illuminated when transmitting data
from the Combi panel.
When a remote relay board is present in the system, each of the 64 relays can be energised
or de-energised using USER menu number 8.
When selected, use the UP (1) and DOWN (5) buttons to choose a relay and then the + (4)
and – (2) buttons to energise or de-energise respectively.
When finished, use the SELECT (3) button to return to the USER menu.
Inhibiting a sensor (14)
During maintenance, it is sometimes required to inhibit the alarms on a particular sensor.
A front panel LED will illuminate if any sensor is inhibited.
Choosing ENGINEER’S menu 14, the UP (1) and DOWN (5) buttons select which of the direct
4-20 inputs will be inhibited. The + (4) and – (2) buttons are used to turn the inhibit ON and
OFF respectively.
Pressing SELECT (3) moves the selection to the CAN networked sensors and the buttons are
used in the same way.
Pressing SELECT (3) again returns to the ENGINEER’S menu.
Changing the direct gas type (18)
Each of the sixteen 4-20mA inputs can have a different gas type which can be changed using
ENGINEER’S menu 18.
When selected, buttons + (4) and – (2) change the channel number and UP (1) and DOWN
(5) will change the gas type (according to the Gas Type library).
There are 8 user definable gases (61 to 68) available in the Gas Type library. When one of
these is selected pressing DIM (6) allows the user to name the gas using UP (1) and DOWN
(5) to sequentially change the alphanumeric characters and + (4) and – (2) to move the cursor
beneath the characters. Pressing SELECT (3) saves the name and returns to gas selection
menu.
Pressing RESET (7) changes this menu to allow the maximum value of a gas to be changed.
The + (4) and – (2) buttons will change the displayed value. Pressing SELECT (3) will return
to the ENGINEER’S menu.
Note: that it is not possible to change the gas type for addressable sensors from the Combi
panel. The gas type is set at the sensor itself and the Combi panel displays the information
received from the sensor.

11
Gas Type Library
O2 1 Oxygen 0-25% two falling alarms
CO2 2 Carbon Dioxide 1000ppm
CO2b 3 Carbon Dioxide 0-30%V
CO2a 4 Carbon Dioxide 0-2%V
H2S 5 Hydrogen Sulphide 0-50ppm
CO 6 Carbon Monoxide 0-250ppm
SO2 7 Sulpher Dioxide 0-10ppm
NO 8 Nitrous Oxide 0-100ppm
NO2 9 Nitrogen Dioxide 0-10ppm
Cl2 10 Chlorine 0-10ppm
H2 11 Hydrogen 0-1000ppm
HCN 12 Hydrogen Cyanide 0-25ppm
HCL 13 Hydrogen Chloride 0-10ppm
NH3 14 Ammonia 0-100ppm
O3 15 Ozone 0-2ppm
C2H4O 16 Ethyene Oxide 0-25ppm
CH4 17 Methane 0-1000 ppm
PH3 18 Phosphene 0-2ppm
LPG%Vol 19 Propane %volume
BUT%Vol 20 Butane %volume
FLAM%Vol 21 Flammable %volume
LPG%LEL 22 Propane %lel
BUT%LEL 23 Butane %lel
FLAM%LEL 24 Flammable %lel
WATER 25 0-100%
COb 26 Carbon Monoxide 0-1000ppm
NH3ppm 27 Ammonia 1000ppm
NH3%vol 28 Range 5.0% volume
HF 29 Hydrogen Flouride 0-10ppm
Temp 30 Temperature -5 to +50˚C
UgM3 31 Microgram per metre cubed oil mist
B2H6 32 Diborane 0-1ppm
SiH4 33 Silane 0-5ppm
Ph3b 34 Phosphene 0-1ppm
F2 35 Flourine 0-5ppm
NF3 36 Nitrogen Triflouride 0-50ppm
LEL%/M 37 LEL per metre, 0-5%
SW Input 38 Switch input 0-100%
(Displays as SW input when not in Alarm, and SW Active when in Alarm.
Note: use channel text to describe this switches function).
refrig 39 0-1000ppm refrigerant (e.g. R22)
benzine 40 Benzine 0-100%LEL
flame 41 flame detector 0-100%
fire 42 fire detector 0-100%
humid 43 humidity detector 0-100%
smoke 44 smoke detector 0-100%
callpoint 45 callpoint detector 0-100%
H2 46 Hydrogen 0-2000ppm
CS2 47 Carbon Disulphide 0-100ppm
H2s 48 Hydrogen Sulphide 0-100ppm
NH35000 49 NH3 5000ppm
AcrylNitrile 50 Acryl Nitrile 0-25ppm
HCL 51 Hydrogen Chloride 0-30ppm
Sih4 52 Silane 0-50ppm
NH3200 53 Ammonia 0-200ppm
VOC20 54 0-20ppm
VOC100 55 0-100ppm
VOC1000 56 0-1000ppm
H2%LEL 57 H2 Flam 0-100%LEL
CO2_2000 58 CO2 0-2000ppm
HEXNEPPM 59 0-1000ppm
Usergas1 61 -
Usergas2 62 -
Usergas3 63 -
Usergas4 64 -
Usergas5 65 -
Usergas6 66 -
Usergas7 67 -
Usergas8 68 -

12
Event to remote relays (23)
The following events can be assigned to remote 1-64 relays by using ENGINEER’S menu 23.
4-20 direct chan fail
4-20 direct chan hialarm
4-20 direct chan loalarm
4-20 direct chan oralarm
CAN chan fail
CAN chan hialarm
CAN chan loalarm
CAN chan oralarm
COMM fail alarm
Main power fail
CAN bus fail
Battery / Standby fail
Pressing SELECT (3) moves to each of these event groups and using UP (1) and DOWN
(5), the channel can be chosen and the + (4) and - (2) buttons decide which relay is to be
operated. Note that it is possible to not drive any relay which is the default and this is
indicated on the LCD as relay O.
Pressing DIM (6) at this point allows relay patterns to be entered which will be output to
the external relays if this event occurs.
Pressing SELECT (3) eventually returns to the ENGINEERS menu after saving the
selections and these relays will now energise when the event occurs.
Dimming the LED’s (11)
The LED’s on the main processor board and the LCD display are normally bright but can
be dimmed to give a more acceptable level of illumination in subdued control room
conditions.
The DIM (6) button on the main panel when pressed will toggle the brightness between
maximum and dimmed for both. The level to which dimming occurs can be set via the
User Menu number 11. This shows the current brightness setting and then using the UP
(1) and DOWN (5) buttons a new dim level can be set and this is shown on the LCD and
on the LEDs themselves. This dim value is stored in none volatile memory for future use
and subsequent power ups. In addition to dimming the LED’s, the LCD backlight is also
dimmed and to enable a balance between LCD brightness and LED brightness, a pot on
the main PCB (RV2) allows LCD backlight adjustment. If a repeater is connected to the
main panel then the dim levels are also activated using the same buttons on the repeater.
Mute the buzzer
When an alarm or fault condition occurs the buzzer on the main processor board will
sound. By pressing the ACCEPT button (1) on the front panel, the buzzer will become
silent. Note: even if the key lock terminal is active to prevent button entry, the mute
function will still silence the buzzer. A jumper near the buzzer on the PCB allows the
buzzer to be isolated, this jumper should normally be fitted.

13
Local and Remote relays
Local relays are located on the main input PCB and are designated to specific
conditions which exist within the Combi system and can be programmed to be normally
energised.
Remote relays are located on one of two 32 channel relay boards and can be
programmed to be operated according to detected events which occur such as alarms
and faults. The first 16 relays can be programmed to be normally energised.
The local relays are as follows (all contacts are rated at 5A 250Vac)
Common Over range alarm will energise if any gas is over range. S.P.C.O
Common High alarm will energise if any gas is in high alarm. D.P.C.O
Common Low alarm will energise if any gas is in low alarm. D.P.C.O
Fault will de-energise if any fault exists in the system. S.P.C.O
Option 5 will energise if voting 5 conditions are met. S.P.C.O
Option 6 will energise if voting 6 conditions are met. S.P.C.O
Option 7 will energise if voting 7 conditions are met. S.P.C.O
Option 8 will energise if voting 8 conditions are met. S.P.C.O
Sounder Relay will energise if a new alarm occurs, and is de-energised
when mute, UP (1), is pressed
A small relay on the front panel energises if a sensor is inhibited.
This includes “power up inhibit” periods
The 64 additional remote relays which are S.P.C.O types can be programmed to operate
on an event as an individual relay 1 to 64. Alternatively the first 16 relays can be
programmed to use patterns. See ENGINEER’S menu 23 Event to Relay.
Modbus set up and indicators
Modbus is a means of obtaining data from the gas detection system via a MODBUS
master controller. The Combi system is a SLAVE to the commands received from the
master via two RS485 twisted pair communication cables. When a command is received
on one of these cables, the reply is sent on the same cable thus giving rise to half duplex
communication. For maintenance purposes, two LED’s situated on the main processor
PCB close to the connectors show when a reply is being sent on that particular cable.
In a MODBUS system that makes use of both these cable, both these LED’s flash
periodically to indicate successful communication. Once the communication has started,
the Combi system will monitor how long since the last command was received and if this
is greater than 50 seconds a communications failure (COMMS FAIL) alarm will occur.
Each Combi system has an internal address, which is used both for Modbus address and
CAN bus address (see repeaters). This address and other parameters can be set and will
be remembered at power up using ENGINEER’S menu 27 Setup Network. The speed of
communication (baud rate expressed in bits per second) is set using menu 34.
All communicating devices in a Modbus system should be set to the same baud rate and
the Combi system is capable of supporting 19200, 9600 and 4800 baud. 9600 is set by
default.

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Set up Network
The addresses of the network sensors are 1-64 so it is normal to have the Combi main
panel address above this, the default address is 201. Using ENGINEER’S menu 27 (set
up network), the address of the Combi can be changed using UP (1) and DOWN (5)
buttons. Pressing SELECT (3) saves this address and presents a view of all other
devices connected to the COMBI.
Using the UP (1) and DOWN (5) buttons each address in the system can be viewed and
if a device exists, a letter will appear to tell you what device is connected.
The following table shows what type of device each letter represents:
P = Combi Panel
C = CAN Sensor
R = Repeater or Network Controller
I = 8 Channel 4~20mA Output Module
S = 4 Relay + Sounder Module
Z = 32 Relay Module
If a repeater is detected, the letter ʻRʼ will appear together with a ‘Y’ or ‘N’,
N means that you are not currently connected to the repeater.
Pressing + (4) will change the ‘N’ to a ‘Y’ to indicate connection and – (2) will change
back to no connection.
When the repeater is connected, the Combi will send text and LED data to it and accept
button presses from the repeater thus allowing remote operation of the combi panel.
Pressing SELECT (3) again returns to the ENGINEER’S menu.
Modbus baud rate
Using ENGINEER’S menu 34, the baud rate used by Modbus can be changed. Pressing
UP (1) and DOWN (5) will alter the baud rate.Pressing SELECT (3) returns you to the
ENGINEER’S menu.
The Modbus protocol for the data packets received from a master is usually a request for
specific data to be sent back to the master. This protocol is covered in a separate
document known as MODBUS RTU protocol. In its simple form, the master will ask for
the data kept in any of the 250 registers located in the Combi system and the Combi will
reply with the requested register data.
These registers are 16 bit numbers representing 0 to 65535 in decimal. A view of these
registers can be seen by using ENGINEER'S menu 1. UP (1) and DOWN (5) will display
different register numbers with the data. It is useful when first setting up the system.
Additionally, ENGINEER'S menu 4 allows you to view the Modbus data packets received
and transmitted. Again, this is used when first setting up the system and can diagnose
requests and responses.
See Combi Modbus register definitions in the appendix.

RS232 data log output
In addition to Modbus, an additional data stream showing actions within the COMBI
system is available via the RS232 output.
This consists of a 3 wire interface which can connect directly into the serial port (RS232)
connection on a PC which is a 9 way D-type female connector (not supplied). This should
be wired to the Combi system as follows.
D-type Pin COMBI RS232 connector (Bottom left of PCB)
2Tx
3Rx
50V
Using Hyper-terminal on the PC set up at 2400 baud 8 bit no parity and no handshake,
the data output should appear on the screen and consists of any text which is being
recorded in the event log.
Event log (9)
The events listed in appendix 1 are logged internally in the COMBI system.
A total of 99 events can be stored and viewed later either on the LCD or on a PC using
Hyper-terminal.
When this 99 event memory is full, the oldest event is replaced by the new event so this
history of events always represents the last 99 incidents.
Using ENGINEER’S menu number 9, this event memory can be viewed one event at a
time using the UP (1) and DOWN (5) buttons to scroll through the sequence. Date and
time of the event is also displayed.
With the RS232 cable connected to the PC and Hyper-terminal in use at 2400 baud the
whole event log can be sent using ENGINEERING menu 28.
Using capture text in Hyper-terminal, this event log can be saved to a file for future
examination or printing etc.
15

Data to and from a PC using hyperterminal
Within the Combi system there are parameters which have to be set such as the text
which describes the location of a particular sensor. Whilst these parameters can be set
manually using the buttons, it is quicker and easier to send a text data file from a PC
using the RS232 interface via Hyper-terminal (which is standard on a Windows XP PC).
The file which is sent is simple alphanumeric characters which can be edited using a
simple text editor like Notepad which is also standard on a Windows PC.
This file can be created from scratch but it is simpler to create it by sending the data
already stored on the Combi panel to the PC again using Hyper-terminal.
This method is now described followed by how to reload the file back into the Combi
main panel.
Using ENGINEER’S menu 30 (Data panel to PC) and the RS232 lead plugged into the
PC COM port.
On the PC, click (for Windows XP)
START
PROGRAMS
ACCESSORIES
COMMUNICATIONS
HYPERTERMINAL
and set the hyper-terminal to the active COM port, at 8 data bits, no parity, 1 stop bit, no
handshake then select Transfer and Capture text, a filename is suggested to save the
data to. You can change this filename as required and do take note of which directory it is
going to be stored in, then press the start button and the PC is now waiting for data to be
sent from the Combi system. (Note it is easier to save this file to the desktop initially).
Using ENGINEER’S menu 30 (Data panel to PC) press select which should send data to
the PC. This data can be seen on the PC screen as it is transferred. When it is complete,
on the PC use:
TRANSFER
CAPTURE
STOP
this saves the data onto the hard disk in the folder specified previously. Each line of text
(shown in the table below) in this file forms particular data as follows:-
A line which does not start with a colon : or an asterisk *is ignored which allows you to
add comments at any point in the text. Colon :indicates data for direct sensors, an
asterisk *is used to indicate addressable sensors.
16

Line Description
:T6, Port Hold 1 This line is the text for direct sensor 6 which will display on the LCD.
For each direct input 20 characters can be assigned.
*T4, AccomBlock This line is the text for addressable sensor 4 which will display on
the LCD. For each of the 64 addressable sensors up to 20
characters can be assigned.
:G1,%LeL^ , This line selects a gas type for gas sensor 1 appropriate gas sensor
must be fitted in the system. All 16 direct types can be selected
(Note: this does not apply to CAN addressable sensors as they
transmit their gas type to the control panel.)
:HiAlarm 2,400 The high alarm point for direct sensor 2 is 400 divided by 10 (40.0).
High alarms can be set according to the type of gas and the value
represents 10 times the actual value (this is to avoid decimal points
in the data).
:LoAlarm 1,200 Ditto for sensor 1 low alarm point.
:OrAlarm 3,998 Ditto for sensor 3 over range alarm
:X This terminates the text transmission to the panel and should always
be at the end of the text. (Note: with the exception of :X, using *T,
*H etc. sets the parameters for addressable sensors) Text lines after
:X is ignored. If an :X is not included in the file then the panel will
eventually time out but this may take a few minutes.
Having edited the text to suit the installation, it can now be sent back to the panel using
ENGINEER’S menu 29 PC to panel.
Again, Hyper-terminal is used but this time the Transfer/Send text file option is used.
When prompted, choose your modified text file as the one to send and then the text
should start to flow. The output seen on the Hyper-terminal screen consists of the
command letters received so strings of T or H, etc are seen which lets you know that all
is well. The final letter seen will be an X and at this point the new data sent is stored in
non volatile memory on the processor board.
Real time clock
On the main processor board a real time clock chip keeps time and this can be set using
USER menu 2 in conjunction with the UP (1) and DOWN (5) buttons and SELECT (3).
To ensure that the clock keeps time when no power is applied, a large value capacitor on
the PCB provides power to the clock for up to 24 hours.
If the processor board is unpowered for longer than this, it is probable that the clock will
have to be reset to local time before use.
It is important to keep the clock correct since this time is used when recording events in
the event log and also for the RS232 output log to a PC.
Refresh Rate
The display of sensor gas levels on the display is cyclical.
ENGINEER'S Menu 5 allows you to change the amount of time that data is displayed;
slower refresh rates tend to be used when the number of sensors is small. Using + (4)
and – (2) buttons this rate can be set to fast ‘1’ to slow ‘10’ or any number in-between. 17

Changing Engineer’s Password
The passwords are present to prevent unauthorised button entry on the control panel and
whilst the user password is fixed, the ENGINEER’S password can be changed.
Using ENGINEER’S menu 33 will allow you to enter a new engineer’s password.
You are prompted to re-enter the new password again as a check and if both are the
same then this password is the new engineers password.
Calibrating Gas Sensors (see setup procedure for sensors)
16 direct 4-20mA gas sensors – source mode
Each of the external gas sensor cards has to be periodically calibrated with its sensor to
produce a 4-20mA signal to input to the Combi (see sensor data sheets C893 & C894)
This signal input to the Combi would produce a 0 to 100% of the signal range but a
further level of calibration trimming is possible at the Combi panel.
To assist in this process, ENGINEER’S menu 20 adjust 4~20mA zero/span will guide you
through the stages of calibration for these direct sensors.
The first step is to select which of the 16 sensors is to be calibrated.
Pressing SELECT (3) moves to the next step which is -
Set the maximum value expected from the sensor e.g. flam is 99.9% Pressing SELECT
(3) moves to the next step which is -
Use the UP (1) and DOWN (5) buttons to adjust the zero on the LCD
Pressing SELECT (3) moves to the next step which is -
Apply span gas and use the UP (1) and DOWN (5) buttons to change the gain until the
reading is correct on the LCD for the applied gas.
The gas values used in this case are the peak values from the sensors and this gives the
ability to apply gas to a number of sensors before returning to the Combi panel to adjust
thus allowing one engineer to set the span. In this case, the zero on these sensors
should be completed before span is performed.
This completes the calibration of the direct 4-20mA gas sensor.
64 Addressable gas sensors
Use ENGINEER'S menu 10 (addressable zero span) on the Combi to calibrate the
addressable sensors. The inhibit LED on all connected sensors will flash. Use the UP (1)
and DOWN (5) buttons to look at all sensor addresses which are being zeroed and use
the + (4) or – (2) buttons on Combi to zero the reading on each sensor.
Press the SELECT (3) button on Combi to enter the span mode which gives plenty of
time to visit each sensor. Gas each sensor with appropriate calibration span gas and
return to the Combi panel.
Use the UP (1) and DOWN (5) buttons to view each sensor address and using the + (4)
or – (2) buttons, adjust the peak sensor reading to be that of the calibration gas. Press
SELECT (3) to exit this menu when all sensors have been adjusted.
Note: peak readings are lost when exiting from this menu. Re-enter the menu and
useagain to calibrate any missed sensors.
18

Cell replacement on Combi sensors
Should a sensor cell require to be replaced, the sensor should have its power removed
before changing the cell itself. Flammable (Catalytic) and Toxic cells have colour coded
wiring which is Pink, Yellow and White which should be connected correctly according to
the markings on the PCB. Fig 5 on page 43 and data sheets C893 & C894 at the end of
this document detail the procedure for setting up a new sensor independent of the Combi
panel and then when connected to Combi follow the above zero and span procedure.
Setting the Time to Alarm
Using ENGINEER’S menu 26, the time in seconds required to detect a direct 4-20 alarm
can be set to a maximum value of 255 seconds. This is useful in certain installations where
transient gas presence is allowed and gas detection alarms quickly become a nuisance.
The UP (1) and DOWN (5) buttons change the channel and the + (4) and – (2) buttons
will alter the time in increments of 1 second.
Pressing SELECT (3) will present the same choice for the addressable channels.
Pressing SELECT (3) again returns to the ENGINEER’S menu after saving these times.
Setting Alarm levels
The high and low alarm points for the sensors can be set manually using ENGINEER'S
menu 21 for direct 4-20 alarm levels and menu 15 for addressable alarm levels.
Menu 15 for addressable sensors
Use UP (1) and DOWN (5), to choose a sensor which requires an alarm change.
Use + (4) and – (2) to adjust the low alarm point.
Pressing SELECT (3) will then request you to set the High alarm point.
Pressing SELECT (3) again allows the Over Range alarm to be set.
Use the RESET button (7) to select RISING and FALLING alarm.
Pressing SELECT (3) again will exit the menu and save the parameters to memory.
Setting Number of Decimal Places (18)
Using ENGINEER’S menu 18, the number of decimal places displayed by the ‘Gas Value’
can be set to 1 or 2. This is global command for direct sensors only. For addressable
sensors the decimal places selection must be set individually at the sensor via PC
hyper-terminal, (see Combi sensor datasheets C893 & C894).
The RESET (7) button changes this menu from the ‘Alter Gas Type’ screen to the
‘Change Range’ screen. On the Change Range screen use RESET (7) to switch between
‘DP=1’ and ‘DP=2’. This toggles the displayed Gas Value between 1 and 2 decimal
places respectively.
Press SELECT (3) to return to the ENGINEER’S menu.
Setting the 4~20mA Deadband (18)
Using ENGINEER’S menu 18, the 4~20mA deadband can be switched ON or OFF.
This is a global command for direct sensors only. For addressable sensors this must be
set individually at the sensor via PC hyper-terminal, (see Combi sensor datasheets C893
& C894). The RESET (7) button changes this menu from ‘Alter Gas Type’ screen to the
‘Change Range’ screen.
19