Global 1120, Руководство по эксплуатации

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Global Power Technologies
1120 - Class I, Division 2, Group D, T3
The ignitor housing is mounted to the heat exchanger with the electrode inserted into the burner
and connected to the high voltage ignitor module.
The electrode is inserted through the burner into the combustion chamber and properly gapped
(1/8” to 3/16” from the combustion chamber wall). The electrode is then connected by the cable
to the output of the high voltage ignitor module and is ready for ignition.
The ignition system operates on 2 VDC applied to the high voltage ignition module, which in
turn generates a 12 kilovolt spark which arcs from the electrode to the combustion chamber
wall. When power is applied the module will generate approximately one spark per second
until ignition occurs and combustion is sustained, at which time flame ionization causes a small
current to flow and holds off the sparking module.
Power to the ignitor assembly is supplied by the electronics assembly (see Figure15) and rout-
ed through the conduit assembly.
Control is by the manual ignition switch of the electronics assembly or the pressure switch of
the fuel assembly.
3 .6 Conduit Assembly: See Figure 27 .
The conduit assembly is a distribution system for the routing of signal and control wires to and
from the fuel system, ignitor system, electronics system and digital panel meter. It consists of a
junction box for distribution and interconnection, flexible conduit assemblies with seals for main-
taining the integrity of assemblies, and a digital panel meter for display of voltage and current
settings. The digital panel meter is not field repairable and requires replacement of both the
display section and monitor board (located in electronic housing) in the event of failure.
3 .7 Electronics Assembly: See Figure 18, Figure 19, Figure 29 .
The electronics assembly consists of a housing assembly, protective limiter, converter, preci-
sion load resistors, voltage sensing alarm circuit, battery charger control module and battery,
protective diode and current shunt, voltmeter input circuits, and all associated switches and
controls. Refer to Figure 29 for physical location of circuits and Figure 18 and Figure 19 for
schematic diagram of these circuits.
3.7.1 Electronic Housing : This box has been designed to meet the requirements of Class I,
Division 2, hazardous areas. It also performs as a heat sink capable of dissipating the
full output power of the TEG when in a set up or no load condition.
3.7.2 Precision Load : Two 0.75 ohm, 50 watt resistors connected in parallel (resulting in
0.375 ohm) as well as their associated wiring, which when switched to the power unit,
give us a precision load resistance of 0.387 ohm (approximately), provide the optimum
load condition for the TEG. This precision load is used for adjusting the TEG and eval-
uating its performance. A load voltage of 6.87 volts would give 120 watts from the TEG.
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