Medem AGDS-MC User manual

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Control & Automation
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AGDS MC
Multi Channel
Gas Detection
System

Medem (UK) Limited
L&M Business Park , Norman Road
Altrincham, Cheshire,
WA14 4ES
Tel: [phone]
Fax:[phone]
Website: www.medem.co.uk
e-mail:[email protected]
Cert No. 10213
AGDS-MC
Multi-channel
Gas Detection System
The AGDS-MC, Gas detection system has been designed for use in boiler houses and plant rooms. Up to 16 low
voltage sensors for the detection of natural gas, LPG or carbon monoxide can be connected to the panel. In the
event of a high alarm from one of the sensors the system will isolate the gas supply by closing a connected
electric control valve. The LCD will display appropriate information about alarm situations and
detector status etc.

Medem (UK) Limited
L&M Business Park , Norman Road
Altrincham, Cheshire,
WA14 4ES
Tel: [phone]
Fax:[phone]
Website: www.medem.co.uk
e-mail:[email protected]
Cert No. 10213
Design Features
• Gas detection of Natural gas, Carbon monoxide and Butane/Propane L.P.G.
• Compact easy to install compact system with long detector life.
• Remote signalling can be connected to B.M.S and fire alarm systems.
• User friendly, digital design means clear system status indication at all times.
• Emergency shut off buttons and thermal links, all low voltage, can be connected.
AGDS-MC

Medem (UK) Limited
L&M Business Park , Norman Road
Altrincham, Cheshire,
WA14 4ES
Tel: [phone]
Fax:[phone]
Website: www.medem.co.uk
e-mail:[email protected]
Cert No. 10213
The AGDS-MC gas detection panel has been designed to accept digital signals from up to
sixteen gas detectors.
The AGDS-MC will accept gas detectors for natural gas,
carbon monoxide and LPG. The detectors can be mixed on
the AGDS-MC as each connected sensor is shown as a
separate item on the panel LCD display. Up to four
combustible or four carbon monoxide sensors can be
connected to the main panel, though a total of 16 detectors
can be connected when used with our transformer pack.
In the event of a gas being detected the panel LCD will show
either pre alarm or high alarm and also which detectors
have alarmed and which gas has been detected.
On high alarm the panel isolates the gas supply
by closing the control valve. At the same time a
BMS and a beacon or sounder can be activated.
The AGDS-MC normally uses 240 volt normally
closed valves but it is possible to run other types.
An emergency shut off button is incorporated on
the AGDS-MC panel and remote emergency shut
off buttons can be connected. Remote emergency
shut off button connections are wired low voltage,
normally closed, open on alarm.
Thermal links can be connected to the system , connections are again low voltage. The
AGDS-MC can also take a signal from a fire panel to close the control valve in the event of a
fire alarm situation.
A fire test isolation panel is available from Medem to allow a fire test to be carried out with-
out isolating the gas supply.
All Medem systems are designed built and supported by Medem UK. The sensors have a
design life of five years when used in clean air environments such as a boiler house.
Continuous exposure to combustible gas will shorten the life of combustible gas detectors.
AGDS-MC

Medem (UK) Limited
L&M Business Park , Norman Road
Altrincham, Cheshire,
WA14 4ES
Tel: [phone]
Fax:[phone]
Website: www.medem.co.uk
e-mail:[email protected]
Cert No. 10213
Technical data sheet
The model AGD-MC consists of a mains powered panel capable of operating up to four combustible gas detectors and
four Carbon Monoxide detectors.
Up to sixteen detectors (combustible or CO) can be connected to the AGDS-MC when used with the external transformer
pack. See separate schematic for wiring the transformer pack, designed for when more than four combustibles are to be
used.
The detectors are connected by low voltage 4 wire cable (typically telephone cable) daisy chained back to the control
panel. The sensor units may be mounted up to 100mtrs from the control unit. The complete system is designed to comply
with the latest CE Directives including the low voltage directive.
This is housed in an IP65 rated ABS enclosure measuring 183mm high x 212mm wide x 97mm deep.
This is also the power pack box size AD-PP.
The LED indications on the panel:
Power on Green
Gas on Red
Alert Yellow
The LCD indications on the panel:
In the event of an alarm situation the LCD screen will display the condition that is causing the alarm and will generally
offer a solution. The LCD display will indicate for the following, emergency shut off button activated, gas leak detected
and which type of gas (with detector number).
Audible indications:
An internal buzzer is provided to give the following sounds:
Alarm, beep every 1 second.
There is an option to disable the alarm buzzer on the panel circuit board by removing a jumper plug.
Relay outputs:
Main valve relay rated at 5 amps to provide a switched live to the main solenoid valve.
230 volt rated potential free changeover alarm relay to activate a remote sounder and or beacon or signal a
BMS system.
Gas detection settings
The combustible gas detectors are pre calibrated at works to detect gas at 5% of the low explosion level
(pre alarm) and at 10% of the low explosion level (high alarm).
The CO detectors are calibrated at 80ppm for pre alarm and 100ppm for full alarm
AGDS-MC

Medem (UK) Limited
L&M Business Park , Norman Road
Altrincham, Cheshire,
WA14 4ES
Tel: [phone]
Fax:[phone]
Website: www.medem.co.uk
e-mail:[email protected]
Cert No. 10213
AGDS-MC
Connections to panel: marked on board
1. Live & Neutral 230 volts supply from 3amp switched fuse spur
2. 230 volts out to gas solenoid valve (5amp relay)
3. Earth connection terminals
4. Gas On BMS relay (potential free contact, mains rated, max load 5amp)
5. Remote emergency stop buttons SELV, multiple buttons connect in series (requires a N/C circuit, open for alarm)
6. Power connections for detectors, Methane, LPG, CO.
7. Comms connections for detectors, Methane, LPG, CO.
8. Unused Option button.
9. Display detectors addressed 9 to 16.
10. Display detectors addressed 1 to 8.
11. Option Switches
12. Learn Detectors - Press after connecting & addressing Medem gas sensors.
13. Enable/Disable Internal toner
14. Optional Dual BMS relay (SELV) - Factory fit only, must be requested at point of order
Option Switches (No 11) Relay A Relay B
Opt A - Off Factory set Factory set
Opt A - On Factory set Factory set
Opt B - Off Low gas alert High gas alert
Opt B - On low & High gas alert Emergency Stop

Medem (UK) Limited
L&M Business Park , Norman Road
Altrincham, Cheshire,
WA14 4ES
Tel: [phone]
Fax:[phone]
Website: www.medem.co.uk
e-mail:[email protected]
Cert No. 10213
AGDS-MC
Additional sensors can be connected ‘daisy chain’
AD-Med-Sensors
Transformer pack box wall mounting
BOARD & WIRING FOR THE AGDS-MC Gas Detection Panel
Mains
Supply
Fuse at
3 Amps
Minimum 2 Sensors, Maximum 4 to be connected to main panel
Do not remove the PCB Board from the box. Use the eye in the middle of the back box for the first mounting. Then use the two holes on the bottom left and right of the box, access to these fixing holes is under the terminal cover.

Medem (UK) Limited
Project House, 19 Dallimore Road,
Roundthorn Industrial Estate,
Manchester, M 3 9NX
Tel
:
: [phone]
Fax::[phone]
Website: www.medem.co.uk
e-mail:[e-mail]
Cert No. 10 13
AGDS-MC Operating and Maintenance
Operation
With the system switch in the off position; the green power LED should be lit and the LCD displaying
the message “Multi Gas Detection System” all other LED’s should be off.
Normal operating procedure for gas (when power is first applied)
 Turn system switch to the on position.
 The gas valve will open, the LCD will display the message “Gas On” and ‘Gas On’ LED will
light.
Maintenance and testing
To test all features the s stem.
With the s stem switch off; the green power LED should be lit; turn the s stem switch to
on:
The LCD will display ‘Gas On’, the ‘Gas On’ LED will light and the gas valve open, gas should now be
available for use.
Verif all gas detectors are being correctl identified b the AGDS-MC;
Remove the AGDS-MC’s terminal cover and locate the “Display Detectors” buttons (see installation
instructions).
Press and hold the button to display on the LCD screen all “learnt” detectors, ensure all detectors
“type” and “ID” are being correctly identified.
With the gas available for use, appl a small amount of the target gas to each detector:
The AGDS-MC will indicate a low level alarm at 5% LEL for combustible gases, 80ppm for CO, and
a high level alarm at 10% LEL for combustible gases, 100ppm for CO.
The detector LED will turn from ‘Green’ (powered) to ‘Red’ (alarm).
With the AGDS-MC in an alarm state;
The LCD will display the message Low Alarm or High Alarm.
The alert LED will light, the tone will sound and the Gas On LED will go out.
The Gas valve will close
There should be a manual operational test on an installed Emergenc stop buttons,
which when operated will isolate the gas supply and remain isolated until a manual reset is
completed.
A yearly test and inspection of the solenoid valve and let by test should be carried out by a qualified
technician i.e. Gas safe registered engineer.
The detectors are designed to have very low drift so recalibration on site is not required but should
be replaced every 5 years in a clean environment but consideration should be given to
replacement after 3 years if contamination is a possibility. A functionality test should be carried out
every 6-1 months.
If at an time there is an alert or the sounder sounds follow these instructions, further
information can be found both in the installation instructions and b contacting Medem
(UK) Ltd.

AGDS-MC Important
Please read this sheet as it contains
important information
Before commencing installation please familiarise yourself to the
equipment by reading the comprehensive installation instructions. If
in doubt then please call 0161 233 0600. Out of hours please call
0 894 684080 or 0 843 355163.
It is a statutory requirement that this safety system is installed and
commissioned to the satisfaction of the manufacturer.
A commissioning certificate must be issued to the end user along
with instructions for the operation of the equipment.
As the Manufacturer Medem UK should commission this safety sys-
tem whereupon a commissioning report will be forwarded to the in-
stalling agent who should provide a copy to the end user.
At the point of our commissioning an individual serial number will be
attached to the system along with a 24 help line number. Photos and
all relevant information for the installation will then be stored on the
Medem site database to be accessed in the event of a call on the 24
hour help line. The warranty period for the panel and sender unit will
then be extended to Ten years.
INS/1004/001

2
AGDS-MC System description
Multi Channel Gas Detection system
System description
The AGDS-MC is a gas detection system designed to monitor the atmosphere for target gases. The system comprises of a mains
powered panel capable of operating up to four detectors (or 16 in conjunction of the AD-PP transformer pack), either
Combustible, Carbon Monoxide, Carbon Dioxide and Oxygen or a mixture of any. The detectors are pre-calibrated by Medem
(UK) Ltd such that they only require to be connected to the panel and functionally tested.
In the event of a high alarm from one of the detectors the system will isolate the gas supply by closing a connected electric control
valve. Emergency stop buttons and Thermal Links can be fitted and a fire alarm can close the gas valve when connected to the
panel.
Control Panel the front of the panel has the following controls and indications:
Emergency Stop Button
On/Off Switch
LED indications:
Power On - green
Gas On - red
Alert - yellow
LCD display: Displaying system status and diagnostics
Low Voltage Gas Detectors
The maximum cable(4 core) length between a sensor and the control panel should not exceed 100 metres, If the distance between
the main panel and the detectors is greater than 20meters 1mm cable should be used on the 12v, 0v terminals..
Combustible detectors are pre calibrated at 5% LEL (Pre alarm) and 10% LEL for the High alarm.
Carbon Monoxide detectors are pre calibrated at 80ppm (pre alarm) and 100ppm for high alarm.
Each detector has a rotary address selector switch (0-F) each detector must be set to a unique address. Once connected and
addressed you are required to press the “learn Det’s” button (12). Once pressed the corresponding detector LED’s on the main panel
will light green.
Each sensor unit has an LED which shows green when power is applied.
Note: There is a warm up period after initial power up of approximately 90 seconds. During this time the green LED will flash once
per second and the output signal will be inhibited. This is to prevent spurious alarms. After the warm up period and on application
of gas, the red LED will light when a high gas alarm level is reached.
Emergency Stop
LCD Screen for clear instructions
System n/ ff
Switch on to open gas valve

3
AGDS-MC Main features
Power at 230
volts from a
3amp fused spur
Connections to panel: marked on board
1. Live & Neutral 230 volts supply from 3amp switched fuse spur
2. 230 volts out to gas solenoid valve (5amp relay)
3. Earth connection terminals
4. Gas On BMS relay (potential free contact, mains rated, max load 5amp)
5. Remote emergency stop buttons SELV, multiple buttons connect in series (requires a N/C circuit, open for alarm)
6. Power connections for detectors, Methane, LPG, CO.
. Comms connections for detectors, Methane, LPG, CO.
8. Unused Option button.
9. Display detectors addressed 9 to 16.
10. Display detectors addressed 1 to 8.
11. Option Switches
12. Learn Detectors - Press after connecting & addressing Medem gas sensors.
13. Enable/Disable Internal toner
14. Optional Dual BMS relay (SELV) - Factory fit only, must be requested at point of order
14
ption Switches (No 11) Relay A Relay B
Opt A - Off Factory set Factory set
Opt A - On Factory set Factory set
Opt B - Off Low gas alert low & High gas alert
Opt B - On low & High gas alert Emergency Stop

4
AGDS-4 Schematic
Earth Connections not shown
3 amp fused spur
230v
EM Stop Buttons,
TT- 0c
Fire Alarm
Series connected
Addressable
Gas detectors
Connect in
parallel
Mains Rated
Potential free contact,
Max load 5amp’s
(latching relay)
Gas Solenoid
230v
Example Medem Gas Detector
Address selector switch: use 1 to 16 only

5
AGDS-MC Detector Information
Detector Location
Detector location will vary dependant on the individual characteristics of the target gas that is being monitored for. The descrip-
tions below describe the position for each detector after considering these characteristics.
Natural Gas
Natural gas detectors should be mounted at high level on a wall approximately 150mm from the ceiling height and avoiding
corners and potential dead air areas.
Natural gas detectors should not be mounted below the height of the top of a doorway for example. This is because as the
gas is slightly lighter than air it will rise filling the room from the ceiling down and will spill through the top of a door opening
into the next room. If the detectors are mounted below this height then it will take longer the gas to reach the detector.
LPG
LPG gas is heavier than air so detectors need to be mounted at low level 100mm from the floor, consideration should be given
to any potential mopping or wet floor height.
Carbon Monoxide
Carbon Monoxide is similarly weighted to air so detectors should be mounted between 1 to 2 meters from the floor.
Carbon Dioxide
Classroom Carbon Dioxide detectors under guidance from IGEM/UP11/Edition2 should be mounted at a seated head height.
However following onsite experience this mounting height can make detectors susceptible to false readings due to direct
breath contact. We would suggest following the guidance for mounting as per a commercial kitchen to reduce the potential for
false alarm readings.
Commercial kitchen Carbon Dioxide detectors should be installed so they monitor the general level of CO2 within the cooking
area. They should be mounted above standing head height and between 1m and 3m from the cooking line. Care should be
taken so they are not located close to the edge of a canopy or in direct flow of the supply or extract ventilation.
For additional information or guidance on site specific requirements please don’t hesitate to contact us.
Detector Testing
Any installed gas detector can be tested by allowing a small amount of the target gas onto the detector head until a change of
state is registered on the control panel.
If the level of gas applied is of the set low alarm level, the LED on the detector will change from a solid green to a flashing red.
The Alert LED and a message indicating a low level alarm detection combined with an audible alarm on the panel will begin.
If the level of gas drops below the set low alarm level the detector LED will return to a solid green and the panels audible alarm
and the Alert LED and LCD message will clear.
Should an emergency shut-off valve be connected to the panel this will remain open during a low alarm level detection.
If the level of gas applied is of the high alarm level or above, the LED on the detector will change from a solid green to a solid
red. The Alert LED and an LCD message indicating a high level alarm detected combined with an audible alarm on the panel
will begin.
Should an emergency shut-off valve be connected to the panel this will automatically close.
Once the level of gas drops below the high alarm level the audible alarm will continue and the Alert LED and LCD message will
remain.
The valve cannot be reinstated until the gases have been cleared and the control panel reset.

6
Remote stop buttons
AGDS-MC
Single Switch TB2
TB1 TB3
To EM Stop connections in
Use terminals TB2 A and TB2 C
To EM Stop connections in
the panel
TB2
TB1 TB3
Use terminals TB2 A and TB2 C
TB2
TB1 TB3
Use terminals TB2 A and TB2 C
Multiple Switches
Wire in series
Remote stop buttons can be connected to the panel terminal marked as “EM STOP” (number 6 ). The remote buttons
must be wired as above in order to provide a “closed contact” for the control panel.

Modern Plant Limited,
Otter House, Naas Road, Clondalkin, Dublin 22
Tel: [phone]
E: sales @ modernplant.ie, W: www.modernplant.ie
Please do not hesitate to call for advice on the
following number:
00353 1 461 4300 oce hours

Modern Plant Ltd are an official
stocking distribution centre for
Emerson Rosemount industrial
flow, level, pressure, analytical
and temperature
instrumentation products.
Modern Plant Ltd offer a wide
range of Stiebel Eltron
products, from instantaneous
hot water heating, stored
water and electric space
heating solutions.
As Irelands official distributor for
Grohe, Modern Plant stock-hold
and display a large range of
Grohe Commercial and
Domestic products including,
showers, taps, frames and
accessories.
We stock a large range of
Bobrick washroom
accessories made from
type304 stainless steel... the
material of choice and quality
for public washrooms.
We are one of Ireland leading
suppliers of Stuart Turner
pumps to suit a variety of
water boosting and water
transfer applications across
multiple market sectors.
Modern Plant Ltd are official
stocking distributors for the
full range of SMC products
and have a wide range of
parts available from our
trade counter.
Modern Plant Ltd is the sole
Irish distributors for the
complete Medem gas safety
product range. Both companies
work closely to ensure the
products remain best in class.
We stock a comprehensive
range of Haws AG emergency
equipment. We also supply
special models to the highest
level of quality as well as
attractive, stylish drinking
fountains and water coolers.
We stock Bonfiglioli power
transmission and control products,
providing automation solutions for
all areas of industry including the
packaging, beverage, textile, food,
ceramic, wood, mining and metal
processing industries.
We stock tapware and shower
solutions for commercial changing
facilities, toilets and accessibility to
people with reduced mobility in
collective facilities. High tech
solutions for healthcare, elderly
care and laboratories.
AMG specialise in quarter turn
rack and pinion pneumatic
actuators with many available
from stock held locally in
Modern Plant.
We are official Irish distributor for all
Metso Automation valve and control
products, including NELES branded
flanged ball valves, rotary plug
valves, segment valves, high
performance off-set butterfly valves,
valve actuators and much more.
Modern Plant Limited, Otter House, Naas Road, Clondalkin, D 22
E: sales @ modernplant.ie, W: www.modernplant.ie
For more information call 00353 1 461 4300