Instruments and Automatics

Main Instrument Panel

As standard the engine is equipped with an instrument panel, comprising instruments for visual indication of the most essential pressures.

Illustrated on fig. 1.

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The instrument panel is mounted flexibly on rubber elements and all manometer connections are connected to the panel by means of flexible hoses, as shown on fig. 2.

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On the engine is as standard mounted an instrument panel.

The following incorporating pressure gauges for the most essential pressures.

Pressure gauge for:

Fig. 1. Lay-out of instrument panel

Fig. 2. Cross section of instrument panel

The connecting pipes to the manometers are equipped with valves which make it possible to replace the manometers during operation.

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Instrumentation

As standard the engine is supplied with the following instrumentation mounted local on the engine:

The actual number of the instrumentation for the plant can be seen on the diagrams for the specific plant in the sections 512-513-514-515-516.

For code identification see 500.20.

Pressostates and Thermostates

The engine is supplied with a number of alarmand shut-down functions. The alarms shall via the alarm panel worn against an abnormal working condition, which can lead to break down and the shut-down functions shall stop the engine before a break down. I.e. a shut-down is "worse" than an alarm because a shut-down is given if the engine could be severe damage by running on these conditions.

As standard the engine is equipped with:

Shut-down Switches for

-too low lubricating oil pressure - inlet engine

-too high HT FW temperature - outlet engine

-too high engine speed (over speed)

Alarm Switches for

-leaking fuel oil

-too low lubricating oil pressure - inlet engine

-too low prelubricating oil pressure (level alarm)

-too high press. drop across lub. oil filter

-too high HT FW temperature - outlet engine

-too low starting air pressure - inlet engine

-too high engine speed (overspeed)

The actual number and type of the alarmand shutdown switches for the plant can be seen in the list "Engine Automatic part list" in this section.

Leakage Alarm (LAH 42)

Waste and leak oil from the comparement, for the injection equipment, fuel valves, high-pressure pipes and engine feed pump (if mounted) is led to a fuel leakage alarm unit.

Normal leakage

C

B

Leak alarm Normal level

A

High level

Leakoil

Alarm

Normal

Waste oil outlet

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The alarm unit consists of a box with a float switch for level monitoring, see fig. 4.

The supply fuel oil to the engine is led through the unit in order to keep heated up, thereby ensuring free drainage passage even for high-viscous waste/leak oil.

Under normal conditions there will always be a smaller amount of waste/leak oil from the comparement, this will be led out through the bore "A" in the pipe "B" as illustrated.

In case of a larger than normal leakage, the level in the box will rise and the level switch "C" will be activated. The larger amount of leak oil will be lead out through the top of the pipe "B".

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Alarm for Prelubricating (LAL 25)

Alarm for missing prelubricating, when the engine is stopped is given by means of a level switch (LAL 25) mounted in the main lubricating oil pipe.

Alarm and Shut-down for Overspeed

When the mechanical overspeed is activated, see 509.01 fig. 2, a micro-switch will release the alarm for overspeed (SAH 81) and activate the shut-down solenoid in the governor.

The latter function is a back-up for the mechanical overspeed.

Purpose

The purpose with the lambda controller is to prevent injection of more fuel in the combustion chamber than can be burned during a momentary load in-crease. This is carried out by controlling the relation between the fuel index and the charge air pressure.

The Lambda controller is also used as stop cylinder.

Advantages

The lambda controller has the following advantages:

-Reduction of visible smoke in case of sudden momentary load increases.

-Improved load ability.

-Less fouling of the engine's exhaust gas ways.

-Limitation of fuel oil index during starting procedure.

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If the system is activated more than 10 seconds, the solenoid valve will be shut off and there will be a remote signal for "system failure".

Fuel oil limiting during start procedure

During the start procedure the lambda controller is used as an index limiter.

Hereby heavy smoke formation is prevented during start procedure and further the regulating device cannot over-react.

The jet system is blocked during the starting procedure until the engine has reached 710 RPM.

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Principles for functioning

Figure 1 illustrates the controller's operation mode. In case of a momentary load increase, the regulating device will increase the index on the injection pumps and hereby the regulator arm (1) is turned, the switch

(2) will touch the piston arm (3) and be pushed downwards, whereby the electrical circuit will be closed.

Thus the solenoid valve (4) opens. The jet system is activated, the turbocharger accelerates and increases the charge air pressure, thereby pressing the piston

(3) backwards in the lambda cylinder (5). When the lambda ratio is satisfactory, the jet system will be deactivated.

At a 50% load change the system will be activated for about 3-8 seconds.

Fig 1 Principle drawing of lambda controller.