Ampcontrol gasguard, Installation, Operation & Maintenance Manual

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GASGUARD IS CONTROLLER Issue: R2, Date: 26/09/2011, CRN: 7502
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. The Controller has six alarm ‘zones’ that allow grouping of input channel set-points and output relays.
2.5.6 Each zone may be configured to:-
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Include a specific or multiple set-point(s) from a specific input channel.
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Include multiple set-points from multiple input channels.
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Include from zero to four of the output relays.
2.5.7 Analogue Outputs
The Controller has three 4-20 mA current repeater outputs to drive remote displays or PLC/SCADA Systems.
The analogue outputs may be set to one of the following modes :-
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Follow a particular channel.
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Follow the highest reading from a number of selected channels.
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Follow the lowest reading from a number of selected channels.
During the start-up delay time when power is applied to the Controller, the follower outputs are
active and will pass on whatever input signal current is present via assigned channels.
The Controller is DIN rail compatible and has been approved to be intrinsically safe for use in a Zone 0 hazardous
area. The Controller must be powered from an Intrinsically Safe power supply with a maximum output of 16.5V.
The Controller is designed to operate with a minimum supply voltage of 12V dc.
A two line Liquid Crystal Display (LCD) combined with a keypad provides an intuitive user interface, providing easy
access and rapid adjustment to all controller settings.
CAUTION!
The user is responsible for maintaining the Ex ia Intrinsic Safety rating by complying with
the “List of Special Conditions” outlined in the certificate ( Appendix C – Approvals ).
2.6 Understanding Gasguard Controller Functionality
The Controller’s operation can be modified via changes to its configuration settings. Configuration changes
must therefore be carried out with an understanding of the Controller’s functional specifications, its
limitations and the effect that configuration changes may have on the system into which it is installed.
Refer to the Controller functional diagrams in Appendix A of this manual.
These diagrams show:-
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Top level block diagram showing connectivity of each Controller section
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Input Channel block showing signal path and user configurable settings.
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Zone block showing alarm routing and user configurable settings
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Relay block showing trigger sources and user configurable settings.
2.6.1 Controller Layout.
With reference to the top level block diagram, the controller is arranged as four input blocks, six zone blocks and four
relay blocks. The basic Controller operation is best understood by becoming familiar with the workings of the ‘Zone
Block’. Zone Blocks are essentially the core of the Controllers input-to-output ‘logic’ functionality.
All six Zone Blocks may be configured to share the same alarm set-point signals and relays. Each configured and
enabled Zone Block will be simultaneously operational, creating relay events based on alarm set-point status,
included relays and vote count.