A contactor will not energise and an authorised technician must prove whether 120 VAC control power is present at the transformer secondary. The exercise grades the complete measurement plan—state, mode, placement, range and expected evidence—before a tool is applied.
Follow the workflow
Select AC voltage and parallel placement while preserving the energised-work boundary. One measurement should answer one branch of the fault tree; collecting numbers without a decision rule creates more ambiguity.
Do this in the product
Open the registered Control transformer secondary case and leave the answer fields untouched until you can justify each choice.
Open the exerciseThe case expects “energised authorised”. Resistance and continuity need isolation and prove-dead evidence; live voltage or current needs competent authorization and rated equipment.
Do this in the product
Choose the circuit state before selecting a meter function so the safety boundary drives the method.
Open the exerciseThe registered plan uses ac voltage mode, parallel placement and a 600 full-scale range. These choices must agree electrically.
Do this in the product
Submit the plan and use the individual server checks to find the first unsafe or non-diagnostic choice.
Open the exerciseThe expected evidence is 120 VAC. A different reading is useful only when it leads to a documented next check rather than an immediate component replacement.
Do this in the product
Save the graded result for a portfolio record or assign it through a paid team training path.
Open the exerciseCore concepts
The simulator creates a repeatable result; these concepts make that result transferable to real vendor software and supervised practical work.
The expected reading and next action are written before the probes move, reducing random fault finding.
Voltage is measured across two points, current through a series path and resistance only on an isolated circuit.
A multimeter result is one item of evidence. It does not replace isolation, category ratings, process knowledge or specialized test instruments.
Continue in the workspace
Run the foundation exercise publicly, then use a subscription for advanced challenges, saved configurations, full attempt history, sharing, assigned paths and team reporting.
Related learning surfaces
Competency and practice field guide
Direct answer
The learner can predict approved measurements, distinguish line-to-line and line-to-reference readings and locate an open secondary control boundary.
Written for electrical maintenance learners interpreting a 120 VAC control secondary, protective device, grounded or floating reference and downstream load path.
Primary isolation, transformer ratio, secondary conductors, bonding arrangement, overcurrent protection, reference point, meter category, expected readings and load state.
Source through primary protection, transformer coupling, secondary protection, control conductor, load, return and approved measurement reference.
Declared secondary readings remain coherent unloaded and under the bounded training load with protection intact.
Open fuse, missing reference, floating secondary, shorted load, loose neutral, wrong meter function, phantom reading, overloaded transformer and power return.
A source, protection, winding, bond, conductor, reference, load, return or measurement-method mismatch.
The circuit reviewed and tested under current codes, drawings, equipment ratings and employer energy-control procedure.
The secondary may be floating, bonded differently than assumed, open through a high-impedance path or measured from the wrong reference. Stop and verify the documented system.
No. Energized work requires employer authorization, risk assessment, appropriate instruments, PPE and procedures beyond simulation.