Ampcontrol Pty Ltd
– ABN 28 000 915 542
DIESELGUARD USER MANUAL
MAG-179 Version 3
– APR/16
Uncontrolled Copy - Refer to Ampcontrol Website for Latest Version
Page 8 of 27
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3
PRODUCT OVERVIEW
The Dieselguard System monitors ambient gas levels (methane for a standard installation) and provides
indication and control based upon the measured gas levels. The system prevents unsafe starting of a
machine in the presence of dangerous levels of explosive gas. Similarly, if a machine is running, the
Dieselguard System will shut the machine down if surrounding gas levels rise above the set alarm point.
This prevents continuing unsafe operation of a machine in a potentially dangerous atmosphere.
Key Features
Gas monitoring and control functionality
IP66 stainless steel enclosure
Ex ‘m’ ia certified product
Powered from machine’s alternator
CH4 transmitters with integrated or remote sensor heads
Standard external control enclosures available
Intrinsically safe solenoid valve
3.1 Diesel Machine Monitor
Figure 3.1: Diesel Machine Monitor
The Ampcontrol Dieselguard Machine Monitor is the central connection point for the Dieselguard system,
which comprises of external sensors, external display, control box and the I.S. solenoid valve. The
Ampcontrol Dieselguard Machine Monitor is housed in a low-profile IP66 stainless steel enclosure, with
all internal electronics being encapsulated.
The Diesel Machine Monitor is an Exm ia certified product that is powered from the alternator supply of
the vehicle. Apart from the supply power all other connection to the Dieselguard Control unit are Ex ia
Intrinsically Safe (IS) circuits.
The Diesel Machine Monitor provides the control via a solenoid incorporated into the diesel machine’s
safety pressure circuit. When released the solenoid allows the system to de-pressurise and as a result,
shut down the machine
Input power is provided via the integral encapsulated cable and is not polarity sensitive. The input
circuitry has been designed to withstand a wide variety of ‘dirty’ power supply types. Many alternators
provide power that has a high level of ripple and high voltage noise spikes. The Dieselguard Diesel
Machine Monitor is designed to withstand these conditions without operational problems. The unit will
withstand a 90V repetitive overload condition via its internal auto-reset protection barrier. The input
power supply circuitry is galvanically isolated from the rest of the system.
The unit is designed as a component approved device and can be used with Intrinsically Safe and