MARL042 — Apply basic principles of marine electrotechnology

1 Explain how material properties affect resistance of electrical conductors

• 1.1Terms and symbols used in the formula for resistivity are used correctly
• 1.2How resistance varies with changes in conductor length and cross-sectional area is outlined
• 1.3How resistance varies with temperature is outlined
• 1.4Calculations are performed that illustrate how material properties affect resistance of electrical conductors

2 Apply Ohm’s Law to electrical circuits

• 2.1Main sources of electromagnetic field (EMF) are identified
• 2.2Terms and symbols used in Ohm’s Law are used correctly
• 2.3Calculations are performed using Ohm’s Law to solve problems involving internal, external and variable resistances in both series and parallel circuits
• 2.4Calculations are performed to determine power required and/or energy expended by electrical devices
• 2.5Circuits for a Wheatstone bridge and a slide wire bridge are sketched and their application on a ship is outlined
• 2.6Calculations are performed dealing with resistances, currents and voltage drops in bridge circuits under null or balanced conditions

3 Apply principles of electrolytic action to electrical cells

• 3.1How the theory of electrolytic disassociation when applied to common electrolytic solutions and electrode materials explains the generation of EMF from chemical sources, is outlined
• 3.2Primary cells are distinguished from secondary cells
• 3.3Calculations are performed to solve problems involving currents, voltage drops and terminal potential difference of cells connected to form batteries in series and in parallel
• 3.4How capacity of a battery is measured is explained
• 3.5Construction of typical batteries used in marine environments is outlined

4 Apply principles of electromagnetism to EMF generation

• 4.1Form and properties of the magnetic fields surrounding single conductor and multi-turn solenoid coils when carrying an electrical current are compared and contrasted
• 4.2Terms and symbols used in Faraday’s and Lenz’s laws of electromagnetic induction are used correctly
• 4.3Calculations are performed using Faraday’s and Lenz’s laws of electromagnetic induction to solve problems related to electromagnetism and EMF generation
• 4.4Fleming’s Right Hand Rule is outlined

5 Explain operation of direct current (DC) rotating machinery

• 5.1Construction and methods of maintaining and repairing typical DC machines are illustrated
• 5.2Principle wiring arrangements used with DC machines are outlined
• 5.3Action of the commutator in DC generators is outlined
• 5.4Significance of Back EMF (Eb) in the operation of DC motors is outlined
• 5.5Mathematical formulae are applied to show relationships between operational parameters of DC motors
• 5.6Calculations are performed to solve simple problems relating to power output and efficiency in DC. motors

6 Explain operation of alternating current (AC) rotating machinery

• 6.1How three phase AC may be developed out of simple single phase AC is explained
• 6.2Difference between Star and Delta connections is outlined
• 6.3How a three phase supply can generate a rotating magnetic field is explained
• 6.4Construction of an AC synchronous generator is outlined
• 6.5Construction of an AC induction motor is outlined
• 6.6Calculations are performed to show how driving torque is produced in an induction motor

7 Explain parallel operation and load sharing of generator

• 7.1Load/voltage curves of AC and DC generators are compared
• 7.2Main requirements for satisfactory power sharing between both AC and DC generators are outlined
• 7.3Sequences that occur when load changes on two DC generators working in parallel without an equaliser connection are outlined
• 7.4Effect of varying power factors on the load/voltage curve of an AC generator is outlined

8 Explain coupling and breaking connections between switchboard and distribution panels

• 8.1Construction, equipment and service of main switchboard and emergency switchboard and distribution panel are outlined
• 8.2Construction and operation principle of measuring instruments in main and emergency switchboards and distribution panels are outlined
• 8.3Construction and operation principle of circuit breakers and their tripping devices are outlined
• 8.4Procedures for restarting ship equipment after power supply failure are outlined
• 8.5Connection between main and emergency switchboards and necessary safeguards are outlined
• 8.6Procedures for changeover to shore-connection supply are outlined

What does an assessment tool for MARL042 need to cover?

To satisfy the Principles of Assessment and Rules of Evidence, an assessment for MARL042 needs to address all 117 unit components: 8 elements with 41 performance criteria, 7 performance evidence requirements, 69 knowledge evidence requirements, and the foundation skills. A coverage matrix mapping each question and task to these components is what an auditor looks for.

How does Auditori generate an assessment tool for MARL042?

Auditori pulls the current release of MARL042 from training.gov.au and generates a complete package: candidate assessment, assessor guide with model answers and observation criteria, and a coverage matrix mapping every component. A suitably qualified person then reviews and approves the draft in a built-in workflow — consistent with ASQA's guidance on AI use in VET — before export as branded PDF and editable Word.

Is the first assessment tool really free?

Yes. Every new account includes one free credit — enough to generate the complete assessment tool for MARL042 — with no card and no subscription required. After that it's pay-as-you-go per unit.

Can I check my existing MARL042 assessment instead of generating a new one?

Yes — upload your existing assessment or learner guide and Auditori maps it against every element, performance criterion, PE and KE of MARL042, showing exactly what's covered and what's missing. Mapping costs a quarter of a credit.