RVT_ELEC_01101 Autodesk Certified Professional in Revit for Electrical Design Questions and Answers

According to Autodesk’s Revit MEP User’s Guide (Revit MEP 2011, Chapter 17 “Electrical Systems”), lighting fixtures in Revit are hosted components—this means they rely on another model element (like a wall, ceiling, or floor) to exist. Specifically, ceiling-hosted lighting fixtures must be placed on a ceiling element that is within the same model file in which the light is being placed.

From the document:

“Most lighting fixtures are hosted components that must be placed on a host component (a ceiling or wall). To place a lighting fixture in a view:

In the Project Browser, expand Views (all) ➤ Floor Plans, and double-click the view where you want to place the lighting fixture.

Click Home tab ➤ Electrical panel ➤ Lighting Fixture.

In the Type Selector, select a fixture type.

On the ribbon, verify that Tag on Placement is selected to automatically tag the fixture.

Move the cursor over the drawing area.The lighting fixture is previewed as you move the cursor over a valid host or location in the drawing area.

Click to place the lighting fixture.”— Revit MEP User’s Guide, Chapter 17: Electrical Systems, p. 402

Additionally, in the Rendering section of the same guide, Autodesk clearly defines hosting relationships in lighting fixture templates:

“The names of all lighting fixture templates include the words Lighting Fixture. Be sure to select the appropriate template for the type of lighting fixture that you want to create. For example, to create a ceiling-based fixture for metric projects, use Metric Lighting Fixture ceiling based.rft.

Revit MEP opens the Family Editor. The template defines reference planes and a light source. For ceiling-based and wall-based fixtures, the template includes a ceiling or wall to host the fixture.”

— Revit MEP User’s Guide, Chapter 50: Rendering, p. 1148

This indicates that the ceiling host must physically exist within the same model environment. If the ceiling is part of a linked architectural model, the lighting fixture cannot attach to it directly because Revit does not allow cross-model hosting. In such cases, a work plane-based or face-based light family must be used instead.

Therefore, among the given options:

A (snapping using nodes) and B (hosted to a ceiling reference plane) are partial actions within a placement workflow, not hosting conditions.

C (defined in the ceiling layout pattern) is incorrect because pattern layout does not determine hosting.

D (placed in the same model as the ceiling) is correct since Revit requires the ceiling host and the light fixture to exist in the same project file for the hosting relationship to function.

Verified Reference Extracts from Revit for Electrical Design Documentation:

Autodesk Revit MEP User’s Guide (2011), Chapter 17: Electrical Systems, p. 402 — “Most lighting fixtures are hosted components that must be placed on a host component (a ceiling or wall).”

Autodesk Revit MEP User’s Guide (2011), Chapter 50: Rendering, p. 1148 — “For ceiling-based and wall-based fixtures, the template includes a ceiling or wall to host the fixture.”

Revit MEP Family Templates Description — Metric Lighting Fixture ceiling based.rft defines the ceiling as the hosting reference within the same model environment.

The parameter “Lighting Calculation Luminaire Plane: Not Computed” in the Space Properties dialog appears when Revit cannot perform a lighting calculation because no valid lighting fixtures are present within that defined space.

According to the Autodesk Revit MEP User’s Guide (Chapter: Spaces and Lighting Analysis):

“Lighting calculations are performed based on the luminaire data available in the space. If no light fixtures are present, the parameter ‘Lighting Calculation Luminaire Plane’ displays as ‘Not Computed’. Revit requires at least one hosted or ceiling-mounted lighting fixture with a valid light source to calculate illumination.”

In this case, although the space has defined reflectance values (ceiling, wall, and floor) and a lighting calculation workplane height (2’-6”), Revit cannot compute the Luminaire Plane because the software has no lighting geometry to reference for the photometric analysis.

Explanation of incorrect options:

A. Missing IES file: This would cause inaccurate photometric output, but not “Not Computed.”

C. Lights not circuited: Circuiting affects load summaries, not lighting calculations.

D. Lights at different elevations: Revit still computes the average luminaire plane even with varied fixture heights.

Thus, the lighting calculation is not computed simply because no lighting fixtures are placed in the space.

In the exhibit, the Label Parameters for the electrical device tag are configured as follows:

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This setup determines how the tag will display in Revit when applied to any device. Specifically:

The Panel parameter (P203 in this case) will be shown first.

A “/” separator follows because it’s assigned as the suffix for the Panel parameter.

The Circuit Number (2,4) is displayed immediately after the slash, with no extra spaces or line breaks.

Since the Break column is unchecked, the values will appear on one continuous line, not split across lines.

Revit documentation for tag creation confirms this behavior:

“When defining label parameters in a tag family, the Prefix and Suffix fields control text that appears before or after the parameter value, while the Break checkbox controls whether the text wraps to a new line.”

Therefore, when the tag is applied to a receptacle on panel P203 and circuit 2,4, the final formatted text will be:

P203/2,4

This corresponds exactly to option B, where the panel and circuit appear on the same line separated by a slash, with no spaces or line breaks.

The warning message — “Can’t create this kind of element in this view in the current mode” — appears when an electrical designer attempts to place a Generic Annotation family inside a model family (e.g., a data device or electrical fixture) that is not configured to host annotation elements.

According to the Revit Electrical Design documentation, Generic Annotation families are 2D annotation elements, and therefore, cannot be created or viewed in 3D model views unless configured as “Shared.” The official guide clarifies:

“You can create generic annotation families and nest them inside host model families so that the annotations display in the project.”

However, this only functions correctly if the annotation is enabled to act independently within the host:

“To allow a nested annotation to be visible and editable when placed in a host model family, the nested annotation must be set to Shared before loading it into the host.”

If the nested annotation is not set to Shared, Revit cannot create or display it in the host’s model view, triggering this exact warning.

Thus, the correct workflow is:

Open the Generic Annotation family in the Family Editor.

Go to Family Category and Parameters.

Check the box “Shared” under Family Parameters.

Save and reload the family into the host electrical device family.

Other options—changing view level, detail level, or annotation orientation—do not resolve this placement restriction.

In Autodesk Revit Electrical Design, each electrical family (such as a receptacle, lighting fixture, or equipment) can contain one or more connectors that define how it interacts with the electrical system. The Load Classification parameter determines how the connected load is categorized in electrical schedules and load calculations (e.g., Lighting, Power, Receptacle, Other).

When a family’s Type Parameter Load Classification does not display correctly (e.g., it shows “Other” instead of “Receptacle” after being circuited), the issue lies in the power connector’s internal parameter not being linked to the family-level “Load Classification” parameter. Revit uses the connector’s classification to determine the load type when it is connected to a circuit — if the connector isn’t associated, the classification defaults to “Other.”

According to the Autodesk Revit MEP User’s Guide (Chapter: Electrical Systems – Creating Electrical Families), it specifies:

“To control how a component reports its connected load type, associate the power connector’s Load Classification parameter with a corresponding Family Parameter. This ensures the load classification in the circuit matches the family definition, rather than defaulting to ‘Other.’ To correct existing families, edit the family in Family Editor, select the connector, and associate its Load Classification parameter with the family’s Load Classification type parameter. Then reload the family into the project.”

This confirms that the correct approach is to edit the family and create or link the Load Classification parameter to the connector’s Load Classification field. Merely changing the connector value (option C) won’t ensure dynamic synchronization between the family type and circuit. Deleting and re-adding the connector (option B) won’t automatically create that link. Option D (editing through the System Browser) modifies instance-level data, not family associations.

Hence, the correct and permanent fix is:

Open the family in the Family Editor.

Select the power connector.

In the Properties palette, click the small Associate Family Parameter button (⚙️) next to Load Classification.

Link it to the family’s Load Classification parameter.

Save and reload the family into the project.

In Autodesk Revit MEP, the Electrical Settings dialog box contains project-wide configuration parameters that affect all electrical systems, including Cable Tray Settings. This dialog allows users to control annotation scales, fitting symbols, and text size for documentation purposes.

The option labeled “Use Annot. Scale for Single Line Fittings” determines whether the cable tray fittings’ annotation graphics automatically scale according to the view’s annotation scale. When this box is checked, the annotation symbol size for fittings adjusts proportionally to the scale of the view.

Similarly, “Cable Tray Fitting Annotation Size” defines the annotation size for cable tray fittings in single-line representations (schematic views or simplified plan representations). Changing this parameter (for instance, from ¾” to ⅛”) modifies the visual representation globally for all cable tray fittings in the project, since the Electrical Settings dialog is a project-wide configuration, not a per-instance or per-view override.

According to the Autodesk Revit MEP User’s Guide (Electrical Systems – Cable Trays):

“Electrical settings define how cable trays and conduit are displayed throughout the project. Any change made to these settings, such as annotation size or use of annotation scaling, affects all related fittings and components in the project model.”

Therefore, once the designer checks the box for Use Annot. Scale for Single Line Fittings and changes the Cable Tray Fitting Annotation Size to 1/8” (3 mm), all cable tray fittings across the entire project will update to reflect these new settings.

In Autodesk Revit Electrical Design, when an electrical designer attempts to control a receptacle (an Electrical Fixture family) with a switch (a Lighting Device family) as part of a switch system, Revit will only allow this connection if the receptacle’s family has been configured as Switchable within the Family Editor.

According to the Autodesk Revit MEP User’s Guide (Chapter 17 – “Electrical Systems”):

“Revit allows you to add elements such as lighting fixtures or receptacles to a switch system only if the family includes a switchable connector. The ‘Switchable’ parameter must be enabled in the Family Editor to allow this connection.”

This means that for the receptacle shown in the exhibit to appear as an available component for switching, the Electrical Connector within its family must have the Switchable property checked. This parameter is found under:

Family Editor → Select Connector → Properties Palette → Electrical - Data → Switchable.

If this option is not enabled, Revit treats the receptacle as a standard unswitched outlet and will not display it in the switch system creation dialog. Once the option is checked, the designer can reload the family into the project and associate it with a switch system normally.

Additionally, the Smithsonian Facilities Revit Template User’s Guide explains this concept as follows:

“To associate receptacles with lighting switches, ensure that the receptacle family has a switchable connector. Without this setting, the device will not appear as an assignable component to a switch system.”

This distinction is important in residential electrical modeling, where switched receptacles are common for plug-in lamps. Lighting circuits can include both Lighting Fixtures and Switchable Receptacles when the family configuration supports it.

Incorrect Options Explanation:

A. A switch system not being created is irrelevant — the issue occurs before system creation.

C. Being on the same circuit doesn’t affect switchability; it affects electrical load connection.

D. Incorrect — Revit supports switchable receptacles if properly configured.

Therefore, the correct answer is B. The receptacle’s “Switchable” option is not selected within the family editor.

In Autodesk Revit Electrical Design, lighting control systems such as single-pole, three-way, and four-way switches are managed using Switch Systems. These systems logically connect lighting devices (switches) to the lighting fixtures they control. For multiple switches (like three-way configurations) to be part of the same control circuit, they must share the same Switch ID value.

In the exhibit, the electrical designer is attempting to add a three-way switch to the existing switch system labeled “b”, but Revit does not allow it. The reason is that the Switch ID parameter of the new switch does not match the Switch ID of the system it is intended to join.

The Switch ID acts as the unique identifier that links all switches controlling the same group of fixtures. If the IDs differ (for example, “b3” versus “b”), Revit interprets them as belonging to separate systems and prevents them from being grouped together.

The Autodesk Revit MEP User’s Guide – Electrical Systems: Lighting and Switch Systems explains this clearly:

“Switch systems are organized by Switch ID. All switches controlling the same lighting circuit must have identical Switch ID values. Revit will not allow a switch to be added to an existing system if its Switch ID does not match that system’s identifier.”

To fix this, the designer must:

1️⃣ Select the three-way switch.

2️⃣ In the Properties palette, locate the Switch ID parameter.

3️⃣ Change its value to match the target switch system’s ID (in this case, “b”).

Once both switches share the same Switch ID, Revit will successfully include them in the same Switch System.

In Autodesk Revit, phasing allows designers to track existing, demolished, and new elements across different project stages. Every model element includes two key phasing parameters:

Phase Created — defines when the element was built or introduced.

Phase Demolished — defines when the element is removed or demolished.

In the provided exhibits:

The project contains two phases: Existing and New Construction.

The receptacle’s Phase Created parameter is set to Existing, indicating it belongs to the pre-existing building condition.

The architectural wall hosting the receptacle is to be demolished during New Construction.

When a view’s Phase is set to New Construction and its Phase Filter is configured to show demolition, only elements whose Phase Demolished equals New Construction will appear as to be demolished. Therefore, the electrical designer must set the receptacle’s Phase Demolished value to New Construction so that it graphically displays as a demolished element in the demolition plan.

As explained in the Autodesk Revit MEP User’s Guide – Phasing and Coordination:

“Elements created in one phase and demolished in a subsequent phase must have their ‘Phase Demolished’ parameter set to that later phase to display properly in demolition views.”

Thus, to correctly coordinate with the demolition of its host wall, the receptacle must be flagged for demolition during New Construction.

In Autodesk Revit Electrical Design, panel schedules display data that originates from the Electrical Circuits category, not directly from the Electrical Equipment or Electrical Fixtures families. Each circuit in a panel schedule represents an instance of an Electrical Circuit object within Revit’s system-based MEP structure. Therefore, to add an additional field like Breaker Type, the parameter must be created and assigned specifically to the Electrical Circuits category.

According to the Revit MEP User’s Guide – Chapter 50 “Electrical Systems and Panel Schedules”:

“Panel schedules display parameters that are associated with electrical circuits, including load names, rating, poles, and breaker information. To include additional circuit information in a panel schedule, create a Project Parameter assigned to the Electrical Circuits category.”

This means the designer should:

1️⃣ Open Manage → Project Parameters → Add

2️⃣ Create a Project Parameter named Breaker Type

3️⃣ Assign it to the Electrical Circuits category

4️⃣ Set it to appear in schedules and tags, ensuring it becomes available for use in the panel schedule template

As noted in the Smithsonian Facilities Revit Template User’s Guide:

“Custom circuit data fields such as ‘Breaker Type’ or ‘Wire Tag’ are defined as project parameters applied to the Electrical Circuits category so they can be displayed in panel schedule templates.”

Incorrect options:

A. Shared Parameter in Electrical Equipment — Electrical Equipment holds overall panel data (e.g., Mains Rating, Voltage) but not per-circuit data.

B. Shared Parameter in Electrical Fixture families — Fixtures are individual load devices, not part of the circuit’s breaker assignment.

D. Project Parameter assigned to Electrical Equipment — would apply to the panelboard as a whole, not to individual breakers in circuits.

Thus, the correct answer is C. Project Parameter assigned to Electrical Circuits, ensuring each breaker in the panel schedule can display its type individually and dynamically.

In Revit Electrical Design, the Selection Box tool is used to quickly isolate and display selected components in a cropped 3D view. When an electrical designer selects conduits or devices in a model and chooses Selection Box from the Modify tab, Revit automatically generates a 3D view bounded tightly around the selected elements, helping coordinate routing in confined or congested spaces.

According to the Revit MEP User’s Guide under “Creating 3D Views”:

“Use the Selection Box tool to create a 3D view that isolates selected elements. Revit automatically crops the view extents to the selected geometry.”

This feature is critical in multidisciplinary coordination because it allows the electrical designer to review specific conduits, cable trays, or lighting paths in context without manually adjusting view boundaries.

In contrast:

Default 3D View (Option B) shows the entire model.

Scope Box (Option C) controls view extents in 2D views or view templates, not instant isolation.

Section Box (Option D) is manually adjusted within an existing 3D view but does not automatically generate a cropped view around selected elements.

Therefore, the Selection Box is the correct and most efficient tool for this task.

In the exhibit, the designer expects the total connected load to equal the sum of the 4 motor loads:

4 motors × 1000 VA each = 4000 VA expected

However, Revit is showing a Total Connected Load of 3606 VA instead.

This difference occurs because Revit applies Motor Demand Factors automatically when a load classification is set to “Motor.” Demand factors modify the total connected load based on electrical engineering rules.

Revit documentation confirms:

“Assign demand factors to load classifications.”

“Demand loads can be shown on panel schedules.”

In the exhibit, the Load Classification shows Motor with a Demand Factor of 117.87%, which modifies the connected load values in the switchboard totals.

Revit is therefore calculating the effective connected load based on the applied demand factor, not a simple arithmetic sum. That is why the panel’s connected load number ≠ 4000 VA.

Before placing spaces in an MEP model that should reflect architectural room names and numbers, the linked architectural model must be set to Room Bounding. This ensures that Revit recognizes the architectural walls and room boundaries, allowing the spaces to reference and display room information correctly.

As the Revit MEP documentation explains:

“Turns on the Room Bounding parameter for the linked model. This step ensures that the Revit MEP project recognizes room-bounding elements in the Revit Architecture project.”

“The spaces use the room boundaries defined by the Revit Architecture project.”

Additionally, the section Using Room Boundaries in a Linked Model details the procedure:

“In a plan view of the host project, select the linked model symbol → Click Modify | RVT Links tab ➤ Properties panel ➤ (Type Properties). In the Type Properties dialog, select Room Bounding.”

Once this setting is enabled, Revit MEP automatically detects the architectural rooms, enabling the designer to place spaces that inherit the architectural room name and number.

In Autodesk Revit’s Electrical discipline, when electrical components such as panelboards are hosted incorrectly (for example, Panel B hosted to Panel A instead of a wall or level), the hosting relationship must be corrected by reassigning the work plane or host. This is essential because hosted electrical elements depend on the geometry or level of their host for placement, alignment, and coordination.

According to the Revit MEP User’s Guide (Chapter 45 “Work Planes and Element Hosting”):

“If a hosted element is placed incorrectly or the host has changed, use the Edit Work Plane or Pick New commands to redefine its host or work plane.”

Here’s how these two tools apply:

1️⃣ Pick New (Option A)

Located under the Work Plane panel on the Modify tab, this command allows you to select a new face or host (e.g., a wall, ceiling, or floor) for the existing component. It effectively reassigns the element’s host without deleting or recreating the element.

“Use Pick New to specify a different face or surface as the host for a component that was incorrectly placed.”

2️⃣ Edit Work Plane (Option E)

This command lets the designer redefine the reference level or named work plane to which an element is associated. For hosted electrical equipment (like lighting or panels), this ensures the object references the correct structural or architectural surface.

“To correct hosting errors, open Edit Work Plane from the Modify tab, and assign a new named plane, level, or face.”

Incorrect Options Explanation:

B. Edit Mounting value – changes only how the panel is mounted (e.g., recessed or surface), not the host itself.

C. Move command – repositions the element but does not change the hosting relationship.

D. Edit Host value – the “Host” parameter is read-only; it cannot be edited directly.

Thus, the correct methods to rehost Panel B from Panel A to the correct wall or work plane are through Pick New and Edit Work Plane, ensuring proper association and maintaining system connectivity.

In Autodesk Revit Electrical Design, when customizing a family—such as a transformer with a housekeeping pad—each element within the family can have its own subcategory under the parent category (in this case, Electrical Equipment). Subcategories are critical for controlling line weight, color, and material properties independently in project views and visibility settings.

The issue described is that the transformer and its concrete pad currently share the same default category (Electrical Equipment) and therefore use identical line weights and colors in plan view. The designer wants the housekeeping pad to display differently — for example, with a lighter or dashed outline.

According to the Autodesk Revit MEP User’s Guide (Chapter: Creating and Editing Families):

“To control the visibility or graphical appearance of individual components within a family, create a new Object Styles subcategory under the parent category. You can then assign any solid or void geometry in the family to that subcategory. When loaded into a project, the subcategory can be independently controlled through Visibility/Graphics (VG) settings.”

This is the exact and recommended workflow for differentiating line appearances between elements in the same family.

Steps to achieve this:

In the Family Editor, open Manage tab ➤ Object Styles.

Under the Model Objects tab, click New to create a new subcategory (e.g., “Housekeeping Pad”).

Set the desired line weight, color, or material properties.

Select the housekeeping pad extrusion in the model.

In the Properties palette, under Identity Data → Subcategory, choose Housekeeping Pad.

Reload the family into the project.

You can now modify or control its visibility independently in project views.

Why the other options are incorrect:

A. Change to void: A void removes geometry, not graphical appearance.

B. Override Graphics in View: Applies only in a single view, not globally across the project.

D. Visibility from context menu: Controls whether the object is visible, not its line properties.

Thus, the most efficient, parametric, and Revit-standard method is to use subcategories within the family to apply distinct graphical controls.