Glossary of terms you will come across during your Phase 2 training.
 Search full text

Browse the glossary using this index

Special | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O
P | Q | R | S | T | U | V | W | X | Y | Z | ALL

Page:  1  2  3  4  5  6  7  8  9  10  ...  107  (Next)
ALL

## &

:

> means greater than -example 2 > 1

< means less than - example 1 < 2

≤ means less than or equal to.

≥ means greater than or equal to.

 Keyword(s): ≤<≥
:

Lambda, a letter from the Greek alpahbet. In automotive engineering, it is used to represent the stoichiometric ratio of the amount of air required to burn a fuel. For example, for diesel, the value is approximately 14.5:1, meaning that it takes 14.5 parts of air to burn 1 part of diesel.

The stoichiometric ratio for petrol is approximately 14.7:1.

:
Pi, Greek letter used to represent how many times the diameter of a given circle will fit into its circumference. This is constant at 3.142. Apprentice cp fitters use this figure for many calculations, for example: when calculating the capacity of an engine; when calculating centrifugal force and when calculating the peripheral speed of a cutting disk.

## 1

:

This is a Perkins designation, and refers to the 1100 series engine. The '4' refers to a four cylinder engine, and the 'D' refers to the common rail engine.

This engine has full electronic control of the fuel system - common rail with electronic injectors.

As of April, 2012, we operate 3 of these engines.

:

This designation refers to the 1100 series Perkins engine. The '6' refers to the number of cylinders, and the 'C' refers to the fuel injection system, which is mechanical, based around a rotary fuel injection pump. This engine is the forerunner of the 1100D common-rail engine. Currently, the section is equipped with 6 1106C engines and 3 1104D engines.

:

During the electrical module, one of the suggested exercises is to construct various electrical circuits such as parking lamps, headlamps (including relays) and glow plug circuits (including solenoid control).

In order to facilitate this exercise, we use 12V electrical training boards. These are boards of steel construction, with a working tray and a base that can accommodate a 12V battery.

This set up allows apprentices to construct the various circuits, and connect the board to an engine fitted with an alternator.

This set up allows each apprentice to wire up all the basic electrical circuits and components found in a typical plant vehicle.

 Keyword(s): 12V electrical training boards
:

This consists of a 12V lamp, with two different terminals. One terminal (the earth terminal) consists of a short cable and a crocodile clip. The other terminal is at the pointed end of the tool. It is used by fastening the crocodile clip to a good earth point, and then using the sharp end of the took to probe wires. If the wires are live, the lamp will glow.

During the induction phase of the course, you will be issued (at your own expense) with a 12V test lamp.

:

The number '18650' describes a battery, similar in size to an AA battery.

An 18650 is a lithium ion rechargeable battery. The correct name is “18650 cell”.

The 18650 cell has voltage of 3.7v and a capacity of between 1800mAh and 3500mAh.

The cell name is based on its dimensions: the cell is 18mm in diameter and 65mm in length.

For comparison purposes, an AA cell is a 14500 cell - 14mm in diameter and 50mm in length

:

One of a series of diodes (the 1N4000 series). They are popular, 1 amp, general purpose, silicon rectifier diodes.

During the Phase 2 course, we use these diodes to make half-wave rectifiers, full-wave rectifiers, and to suppress voltage spiking on 30 amp relays in circuits such as the time-delay circuit built as part of the Electrical Module.

 Keyword(s): 1N4001

## 2

:
Crow's foot tool that allows you to tighten injector pipe unions with a 3/8" torque wrench.
 Keyword(s): 276-1216

## 3

:

### 3 Effects of electricity:

1. Chemical change  - For example, the electrolyte in a battery changes from sulphuric acid (H2SO4) when the battery is charged, to water, H2O, when the battery is discharged.
2. Heat - For example, current passed through a bulb causes the filament to glow white hot. This is incandescent heat.
3. Magnetism - for example, when we pass electrical current through the commutator and the field windings of a motor, like poles come into close proximity. These poles repel each other, giving us the motoring action.
 Keyword(s): three effects of electricity
:

DIN numerical wiring code:

Other codes you will come across on Phase 2 training include:

• 85: End of coil (for example, the end of the coil windings on an electromagnetic relay)
• 86: Start of coil (for example, the start of the coil windings on an electromagnetic relay)
• 87: To load (for example, on an electromagnetic relay, battery positive is supplied to terminal 30 on the relay. That leads to a set of contact points, and the far side of those contacts is terminal 87, which leads to whatever load the relay is serving.

 Keyword(s): 15live under key31
:
Injector clamp bolt.
 Keyword(s): Injector clamp bolt

## 5

:

Also written as 50 Hz or 50Hz.

This is the frequency at which mains electricity in Ireland is delivered at.

We know that in an AC circuit, rather than flow constantly in one direction, the electrons move rapidly back and forth. The rate at which these electrons move back and forth is referred to as the frequency of the supply. In Ireland, the mains AC supply has a frequency of 50 Hz. In other words, the electrons in our homes move back and forth in the wires 50 times every second when a circuit is closed.

:

The 555 Timer IC is an integrated circuit (chip) implementing a variety of timer and multivibrator applications. The IC was designed by Hans R. Camenzind in 1970 and brought to market in 1971 by Signetics (later acquired by Philips). The original name was the SE555 (metal can)/NE555 (plastic DIP) and the part was described as "The IC Time Machine". It has been claimed that the 555 gets its name from the three 5-kohm resistors used in typical early implementations, but Hanz Camenzind has stated that the number was arbitrary. The part is still in wide use, thanks to its ease of use, low price and good stability. Read more...

 Keyword(s): 555 chips

## A

:

This is a hard covered folder for holding any course notes you may write up, and for any diagrams you may draw.

It is important to get into the habit of writing up your notes on a regular basis. To that end, you are supplied with a spiral notebook and black and red pens. During induction, you will also purchase a geometry set and a pack of markers.

:

During your phase 2 training, it is important that you take and write good notes on the course material. You should also get used to drawing detailed diagrams of vehicle and machine components.

In order to help you do this, you will be issued, free of charge, a spiral notebook and an A4 refill pad. As you fill these pads and notebooks, you will be given new replacement items, also free of charge.

:

This is a qualification awarded by the Institute of the Motor Industry.

:

Anti blockier system, or anti-lock braking system, an electronically controlled system that senses the relative speeds of road wheels in order to determine whether braking wheels have locked up and began to skid. If they have, the system overrides the braking effort supplied by the driver, and frees the brakes until the wheel begins to turn again (stop skidding).

The system is informed by speed sensors at the wheels. These same sensors can be used to feed into a traction control system.

 Keyword(s): Anti-lock brakingAnti-lock brakesantilock brakingantilock brakes
:

Acceleration is simply a change in speed.

Acceleration can be positive - an object speeds up, or it can be negative - an object slows down.

The kind of acceleration we all experience every day is the acceleration produced by gravity - 9.81m/s2, referred to as 'g' in engineering calculations.

For example, in order to calculate the weight of an object, we multiply its mass by the acceleration produced by gravity:

W=m.g

:
During Phase 2, you will spend a lot of time working with lead-acid batteries. In order to protect your body and clothing from acid, you will be issued with an acid-proof apron.

You will also be issued with acid-proof gloves to protect your hands against acid.

You should wear the gloves, apron and your safety goggles whenever you work with lead-acid batteries.

 Keyword(s): acid proof apron
:

During Phase 2, you will spend a lot of time working with lead-acid batteries. In order to protect your hands from acid, you will be issued with acid-proof gloves.

You will also be issued with an acid-proof apron to protect against acid spillages.

You should wear the gloves, apron and your safety goggles whenever you work with lead-acid batteries.

 Keyword(s): acid proof gloves
:
This alerts the operator or the service technician that an electronic system malfunction is currently present. Refer to the term Diagnostic Code in this glossary.
 Keyword(s): Active diagnostic codes
:

Imaginary lines drawn through the king pin and the track control rod end on each side of a vehicle will intersect at a point just in front of the rear axle of that vehicle. The angle they make with each other is known as the Ackermann angle.

The purpose of the angle is to allow the front wheels to turn through different angles when cornering. This is because the inside wheel always needs to turn through a bigger angle in order to get around the corner without scrubbing.

:

Word formed by using the first letter of other words, for example:

RAM-Random Access Memory

:

Unlike a passive sensor, an active sensor needs a power supply. There are 3 terminals on a pressure sensor. One is a supply, one is ground, and the third sends a signal back to the ECM.

Here, we can see the example of a pressure sensor. There are 3 terminals. We know this is an active sensor because it has these 3 terminals.

1. Pin A is a 5 volt supply into the sensor.
2. Pin B is common, meaning it is grounded to 0 volts.
3. Pin C sends a signal back to the ECM. From this signal, the ECM calculates the pressure acting on the sensor.
:

In certain course modules, such as the small plant module, there are activity sheets for you to download. Once you do this, you should work your way through the sheet, carrying out all the activities listed, and researching answers to all the qeustions asked by searching this website, your own course notes and the world wide web.

The small plant module covers a large range of machinery, so it can be very difficult to cover everything.

Acitvity sheets will guide you to study all matters related to health and safety, theory and practical work. If you do all activity sheets, you will not come across anything in the practical or theory exams that you have not already researched as you worked your way through the activity sheets.

 Keyword(s): Activity sheets
:

A needle-like probe used in automotive diagnostics when probing wires and connector blocks for electrical signals.

It is very easy to cause damage to wires, their insulation and to connector blocks when trying to diagnose electrical problems. You must make good metal to metal contact with electrical circuits to analyse them, but it is essential you do not cause any damage when doing so.

An acupuncture probe is smooth and pointed, allowing you to slide the probe into connector blocks without causing damage. The probe then connects to your voltmeter or oscilloscope by way of the standard 4mm connector.

 Keyword(s): acupuncture probes
:
This denotes a self-learning system.
:
This is a software process that is performed in the ECM that optimises engine performance.
:
Sometimes, course participants may feel they can add more to an explanation given in this glossary. In cases like this, they can add comments. See the comment at the bottom of this entry. (Please note: comments are only visible to registered users who are logged in.)
:
This is content over and above what is on the Phase 2 syllabus for CP Fitters.
It is sometimes posted on the site in order to help apprentices who may wish to find out a little more about certain topics or equipment that is covered during Phase 2.
Additional content will not appear in any Phase 2 examinations.