ETCP Entertainment Electrician Practice Test

These questions are part of the practice quiz. Start practicing

• What material is BEST for temporary hanging of 15 conventional luminaires?
• A portable switchboard with a nameplate rating of 640A 3-phase is fed with a balanced load of 267A per phase. What is the minimum ampacity needed for the ungrounded portable feeders?
• In a theatre installation, how are feeders sized?
• What is the minimum meter category for measuring the load side of a 120/208V transformer in theatrical work?
• According to ANSI E1.11 USITT DMX512, which connector family is specified for DMX512 cables?
• In the given light plot, how many control channels are allocated to the 100-PAR 64/1K fixtures?
• In the U.S., an assembly occupancy should comply with NEC Article 520 under which condition?
• Which action should be taken after experiencing an electric shock with no symptoms?
• Arc-flash hazard analysis results are typically expressed in which unit?
• What is the difference between a switch and a breaker?
• For patching a 96 x 2.4kW touring dimmer rack that has a patch bay, which document is most useful to accomplish this task?
• Which point in the three-point truss distribution carries 310 lb?
• Which of the following are concerns of entertainment electricians regarding OSHA/OHSA compliance?
• An entertainment electrician arrives at a venue to find that only a breaker in a panel serves a company switch. This requires the installation of tails. Which of the following is the safest way for the entertainment electrician to proceed?
• If it is necessary to work on live electrical equipment because lockout/tagout is not feasible, which personal protective equipment is necessary for working on 240V equipment where the available fault current is not known?
• How do you calculate voltage drop on a stage run?
• During troubleshooting of portable distribution for a dimmer system, excessive heating is observed on a neutral conductor. Which correction is most likely?
• A power distribution panel with a wooden and fiberglass case catches fire, and the disconnect is not easily accessible. Which type of fire extinguisher should be used?
• A three-phase motor operates correctly when wired in phase order A, B, C. If phases A and B are swapped, what will happen when the up button is pushed?
• NFPA 70E is primarily used for what purpose?
• SOW and SOOW cords are rated for how many volts?
• An entertainment electrician is developing a labor estimate for a shooting crew. The company will shoot in two locations. The first location requires four aerial lifts rigged as lighting platforms with two generators. The second location requires three aerial lifts rigged as lighting platforms with two generators. One lift will remain lit in the first location when the company moves. Each aerial lift requires one lighting technician with no other duties. Each generator will require one lighting technician with no other duties. The chief lighting technician needs 8 technicians in addition to the assistant chief lighting technician on the set. In addition to the chief, which of the following is the minimum number of lighting technicians required for the shooting crew?
• How many control channels are used for the 75-source 4 lekos with 575W each in the plot?
• An entertainment electrician has been tasked with addressing and patching a group of moving lights with a 19-slot footprint that will be controlled from a single opto-splitter. If the first available DMX slot at the console is 451, how many of the fixtures can the entertainment electrician patch?
• A light plot shows 18-575W conventional units controlled by 9 channels. What is the minimum number of 2.4K dimmers required for this hookup if sufficient two-fers are available?
• What does RDM stand for in DMX control?
• If a GFCI trips during a show, what is the proper procedure?
• An entertainment electrician is laying out a rig with 100 color scrollers in various positions in a theatre: front of house, overhead electric pipes onstage, side booms, and an upstage ground row. The control console supplying DMX512 for the scrollers is in the front of house with a 200 ft. run to the stage. The stage is 50 ft. deep and 50 ft. wide. For minimum voltage drop, the color scroller system will be BEST served with
• What is the function of the IGBT switch in a reverse phase dimmer?
• Name two common flexible cords used for temporary stage power.
• The above graphic is equal to DMX 001. Which switches should be switched on to address a luminaire to DMX 084?
• An entertainment electrician is focusing a luminaire, and the lighting designer asks the electrician to flag the unit. What is the lighting director asking to do?
• With an auto-ranging lighting instrument, a power cable has green/yellow, brown, and blue conductors. What is the correct pin-connector wiring order?
• What is the primary purpose of a DMX terminator at the end of the DMX cable chain?
• Why is load balancing critical on a three-phase distribution?
• Which set of tools allows an entertainment electrician to assemble a typical Cat5 data cable most easily?
• Which of the following is a valid IP address?
• Which of the following is the BEST reason for powering up a large rig in sections?
• What is the voltage between two hot legs in a 120/208V three-phase system?
• Which Cat5 data cable assembly tool set is essential for on-stage work?
• According to fall-arrest harness safety, the correct attachment point for the lanyard is where?
• Which device is used to distribute a single power feed to multiple branch circuits in a theater?
• A 480V delta to 208Y/120V transformer has load current of 1000 Amps per phase on the secondary. What is the most accurate current in L1, L2, and L3 on the primary?
• Keeping voltage drop within recommended limits helps ensure what?
• North American standards require a GFCI to trip at what leakage current level?
• Which color indicates grounding in stage electrical installations?
• Which of the following cables is permitted in a breakout?
• Which statement best describes a requirement when applying tap rules for a rolling dimmer rack?
• Which statement best defines a continuous load under NEC?
• In a lighting rig, what is the minimum number of dimmers required when the plan calls for five dimmed channels?
• How should temporary outlets on stage floors be marked?
• The miscellaneous set power is rated at 300A. What is the current rating?
• An entertainment electrician has received a shock that has thrown him off his feet. He is breathing normally and reports no discomfort. What is the proper course of action?
• What does a circuit schedule map?
• In a rooftop setup where the house power is 480V delta and loads include three 18K Fresnels at 208V, six 6K PARs at 208V, six 2.4K PARs at 120V, and 300A of miscellaneous 120V set power, what is the approximate current per leg drawn from the house system?
• For a production involving a river of blood, which feeder cable type is most appropriate according to NEC NFPA 70?
• What is the last step required of lock out/tag out safety procedures for electrical equipment?
• Arc-flash risk assessment and PPE guidelines are components of which standard?
• What is a general rule of operation used by a GFCI on a 120/240 VAC circuit when a fault is not present?
• What is the importance of labeling circuits and cables in a live event electrical system?
• In a 208Y/120V system tapped from a switchboard, what is the line-to-neutral voltage?
• In a DMX512 application using an RDM bidirectional control signal, which pins of a standard XLR-5 connector carry the RDM signal?
• In a DMX system, if the first device fails and downstream units do not respond, what is the most likely fault?
• Which statement correctly describes a 208Y/120V service?
• What is a defining feature of Remote Device Management in DMX control?
• In distribution, what is the purpose of a jumper?
• What is the purpose of a cable ramp?
• To BEST deal with a non-sinusoidal load, an entertainment electrician should use a transformer with
• Under which condition could a 200A (208Y/120V) company switch BEST be used to connect a 400A (208Y/120V) power distribution chassis?
• What is the main function of a stage power distro panel?
• Why is bonding to earth important in stage electrical installations?
• Why would an entertainment electrician order donuts in the context of gobos?
• Define a continuous load per NEC and its implication for ampacity.
• What does SJOOW stand for and where is it used?
• Which instrument is commonly used to verify outlet polarity in new installations?
• Which statements describe the MOST important issues to consider to perform live work safely?
• What is the most common service found at a company switch in North America?
• Which feature does a PDU provide besides distribution?
• Which of the following BEST describes the 'tap' rules, which allow larger breakers or different locations under certain protective conditions?
• In a 120/208V service, what is the typical line-to-neutral voltage?
• A rig uses 36 chain hoists to lift a lighting truss. Due to availability of equipment, one system operates 12 hoists and the other operates 24. Where should the controllers be located for the BEST operation of the system?
• How many data slots are available in a single DMX512 universe?
• What is the safe maximum DMX512 cable length per universe before repeaters are needed?
• What is the wattage of MAC 600s?
• Applying the tap rules in Article 520, a company has a fused 400A disconnect, a rolling dimmer rack with a 100A main breaker, and 80A connected load. Which setup is permissible?
• A lighting truss weighing 1.5 tons, evenly distributed, is hung using three chain motors: one in the center and one at each end. What is the MINIMUM rating of the motors required to safely support the truss?
• In a setup where the video department requests an isolated ground, which point is BEST for connecting the isolated ground?
• Which statement about DMX512 cable length and repeaters is correct?
• What color is the equipment grounding conductor in the US?
• In a DMX universe with five fixtures patched sequentially, each using 3 slots, if the first fixture starts at address 1, what is the start address of the fifth fixture?
• Which statement best describes the use of 208V in stage power?
• On a film set, a sustained load of three 24 kW Fresnels (240 V) is powered by a three‑phase generator set to single‑phase. Which generator size is the MINIMUM required to power the luminaires?
• In a 208Y/120V three-phase system, what are typical hot conductor colors?
• An entertainment electrician is metering the load side of a transformer supplying 120/208V. Which meter category is the minimum that should be used?
• Which PPE must be used when changing a Xenon arc lamp?
• What is a panel schedule and why is it important?
• Two devices connected with an Ethernet switch cannot communicate, though both show powered indicators. The MOST likely cause is what?
• In a venue using a generator feeding a transformer to supplement power, which bonding scheme is MOST appropriate?
• If a cable weighs 0.75 lb per foot, how much does a 20-foot run weigh?
• What is the wattage of a MAC 2000 profile?
• DMX512 is used to transfer control data for lighting fixtures.
• What does 'patching' mean in lighting control?
• A temporary hanging position needs to be created for 10 conventional luminaires. Which pipe should be used?
• Which statement best describes the difference between bonding and grounding in stage equipment?
• What is the total weight carried by the three hang points in the truss example (SR 700 lb, C 1100 lb, SL 310 lb)?
• Which statement describes the function of a circuit breaker?
• How many dimmer racks are in the available inventory?
• Which NEC article governs temporary theatrical wiring?
• Which configuration uses the LEAST amount of inventory to power all the units shown on the light plot, given the available inventory?
• ANSI E1.23-2010 for theatrical fog effects cuing specifies that timing and duration should be set by whom?
• Which terminations does an entertainment electrician need in order to install a set of tails to a generator?
• What is Lockout/Tagout and when is it used?
• During a site study, a 400 A, 120/208V service is available with 30 switches. What is the maximum number of 120V, 575W incandescent fixtures that can be used?
• If a company switch panel shows conflicting ampacity markings, what is the BEST method to definitively determine the ampacity?
• In a scenario where a lighting load requires 3-phase 208Y/120V service (400 Amps) but the building only has 240V high-leg delta (600 Amps) available, what is the best option to connect the lighting system to building power?
• Why is phase rotation important in three-phase stage power?
• In a single-purchase counterweight system, a 1000 lb electrified scenery starts to shoot toward the grid and then stops when it is fully off the saw horses. The most likely cause is:
• Which document lists all circuits, loads, and destinations in a panel and helps with safety and troubleshooting?
• In a DMX system, what is the primary purpose of DMX opto isolators?
• To help handle non-sinusoidal loads, choose a transformer with which characteristic?
• Which statement describes how a DMX universe is delivered from a console with DMX outputs?
• A 48-dimmer portable switchboard has 48 loads of 1 kVA each. What is the total connected load in kVA?
• What is the primary purpose of an overcurrent protective device in a theater feeder system?
• With 10 racks of 96 dimmers (each rack has one DMX input) and 1 rack of 48 dimmers (one DMX input), and a conventional lighting console with four DMX outputs, what is the minimum number of DMX universes required to drive all racks, assuming no two dimmers share an address?
• What does a 15A/125V rating on a receptacle indicate?
• A touring entertainment electrician is converting a three-phase four-wire power distribution to a single-phase three-wire plus ground system in a venue. If the load is 96 amps per phase on the three-phase system, what minimum amperage per leg is required in the new venue?
• How does NEC 525 allow temporary stage wiring to be installed?
• A venue has an incoming service rated for 300A on a 30. Which approach BEST assures a successful load-in?
• What is the rated service capacity of the delta service available in the described scenario?
• Why must feeders in theatre installations consider voltage drop in addition to total load and ampacity?
• In a DMX512 system, 10 devices are patched in a single universe, each requiring 3 slots. How many DMX data slots are used?
• What is best practice for patching moving lights with DMX to avoid channel conflicts?
• When a three-phase motor runs in reverse rotation, which action will correct the rotation?
• In a 120/208V three-phase system, what is the voltage between any two line conductors?
• What voltage do most stage lighting circuits run at in the US?
• A follow spot puts out 100 fc at 200 ft. with a maximum beam size of 40 ft. What is the maximum beam size and number of footcandles at 100 ft?
• What is the safety guideline regarding daisy-chaining extension cords?
• In a three-conductor lighting cable using brown, blue, and green/yellow, which conductor is the hot (live) line?
• What is the arc-flash risk assessment in NFPA 70E used to identify and plan for?
• Which practice minimizes inrush when energizing a large entertainment rig?
• Arc-flash hazard analysis results are typically expressed in which unit?
• A NEMA 5-15P plug is connected to a NEMA 5-20R receptacle. What is the maximum current this connection can safely carry?
• Which combination of items MUST be included on lockout devices?
• When can a Class A GFCI be used for circuit overcurrent protection?
• How many dimmers are in the rack described in the feeder-dimension problem?
• How should equipment grounding conductors be sized relative to the circuit?
• Which of the following allows an entertainment electrician to disconnect power from a system?
• On a twist-lock-style connector, which type of pins connects first when mating?
• Which DMX512 device is used to distribute a single DMX signal to multiple devices while preserving signal integrity?
• A 96-dimmer rack with 2.4 kW dimmers is analyzed for feeders. If all branch circuit breakers are loaded to full rating, the per-phase feeder current is closest to what value?
• Best practice when a long run shows overheating at a connector?
• Which standard governs the cuing operation for theatrical fog effects?
• An existing fixed switchboard has 12kVA on phases A & C and 24kVA on phase B. A 200A, 208Y/120V company switch is tapped from the bus. To attach a 48-dimmer portable switchboard with 48 loads of 1 kVA each, what is the smallest upstream 3-phase transformer required?
• What is the maximum number of 3-slot devices that can be addressed in one DMX512 universe?
• In a DMX universe where fixtures are patched sequentially in 3-slot increments, what is the end address of the tenth fixture if the first fixture starts at address 1?
• What is the maximum 120V simultaneous load that can be continuously energized on a 6-circuit 20A borderlight cable?
• The NEC 125% rule applies to sizing of conductors for what type of loads?
• In a pre-show check, a non-functional, remote control followspot is found in an overhead position. What is the BEST course of action?
• For a 120/208V service with neutral, what is the typical line-to-line voltage?
• Which statements about the connection that returns fault current to the source are true? 1. make first 2. make last 3. break last 4. break first
• A touring entertainment electrician notes that a longer cable run caused intermittent motor operation. What is the MOST likely cause?
• Two lighting circuits are run from the same distribution box with 208V. If the load on Circuit 2 shows 190V at the load, what technique is MOST appropriate to correct the problem?
• What was the available house power service in the rooftop helipad scenario?
• What is required before working around energized conductors?
• When supplying power for a chain motor control center with 20 motors lifting a truss ceiling, the power calculation should be based on what percentage of full-load amps?
• How many channels does a DMX512 universe support?
• Which voltage is commonly used to power HMI fixtures?
• To minimize voltage drop when powering a large number of fixtures distributed across a theatre, which approach is most effective?
• During testing of a branch circuit from the dimming system, the voltage reads 90V with no load while the dimmers are set at 0 from the control console. What is the most likely cause?
• A 1000W load is being plugged into a 20A circuit using a listed extension cord. The minimum wire gauge of the extension cord is BEST determined by
• What is the maximum discrete number of data slots available across three DMX512 universes?
• Define a pigtail in electrical wiring.
• In a 208Y/120V system, what voltages correspond to L-N and L-L?
• The first color scroller in a string of units has blown its fuse due to the gel string ripping. There are several more scrollers daisy-chained downstream of this unit that will not respond at all to console commands. What is the most likely reason the downstream units will not operate?
• An entertainment electrician must supply power to a film set that is 600 ft away from the generator. Which of the following is the MOST efficient sequence to supply 400A, 120/208V?
• What is a closed-lid stage receptacle and when is it used?
• Which voltage drop percentages are typically acceptable for feeders and branch circuits?
• In a 120/208V three-phase system, what is the phase-to-neutral voltage?
• When using portable truss sections to support multiple fixtures, what is a key safety principle?
• In a three-point truss arrangement, which load distribution is the heaviest among the three supports?
• What is the purpose of a circuit breaker in stage power distribution?
• What is best practice for labeling stage circuits?
• What unit is used to measure arc flash energy?
• Which point in the three-point truss distribution carries 700 lb?
• How do you verify proper outlet polarity on a new installation?
• In a 208Y/120V system, what is the voltage from any hot conductor to neutral?
• A lighting position has 8 LED fixtures controlled by the console. Each should be controlled separately, but fixtures 2 and 7 are currently operating in unison. What is the MOST practical troubleshooting step?
• What is the recommended approach to safely power moving stage equipment?
• What is the function of the neutral conductor in a 120V circuit?
• Which voltage do the 18K Fresnels require in the described rooftop setup?
• Which voltage do the six 6K PARs require in the described rooftop setup?
• What is the FIRST action an entertainment electrician should take when hanging 1,000 lb of fixtures on a single-purchase counterweight batten?
• Which document is specifically used to map circuit names to patch bay connections for dimmer racks?
• An entertainment electrician observes that during power-up, a group of three POE devices do not power up properly. Occasionally, one of the three devices does not power up, but not always the same device. All three devices are connected via CAT5 cable to a POE 8-port Ethernet switch. Which of the following should an entertainment electrician do first to troubleshoot the issue?
• A technician measures the voltage at a branch circuit distribution and reads 120 V at the panel. According to NEC/CEC, what is the minimum voltage allowed at the point of use?
• Where is the BEST location to bond a generator when some loads are on the generator and others are on the building's distribution panel?
• When connecting a 96 x 2.4k dimmer rack to its power feed, in what order should you perform these steps: 1) connect white neutral; 2) connect green ground; 3) connect phase legs; 4) shut down power feed?
• Which statement best differentiates a feeder from a branch circuit?
• Which voltage do the six 2.4K PARs require in the described rooftop setup?
• Which assignment BEST describes the function of softpatch on a conventional console?
• What conductor size is commonly used for a 20A stage branch circuit?
• When handling or disposing of fluorescent lamps, which hazard must be considered?
• Why is a detailed circuit and cable labeling important?
• Why is weatherproofing important for outdoor stage power?
• What describes a power distribution unit (PDU) and its purpose in theatres?
• A lighting plot shows 30 conventional lighting units on the first electric, listed at 40 lb. each, evenly spaced. When moving into a venue with counterweight line sets on 6 in. centers rated at 750 lb. each, with 40 ft. 1-1/2" pipe, which of the following solutions is both safe and practical?
• What safety practice should be used to prevent accidental energization during servicing?
• If DMX addressing is incorrect for multiple fixtures, what is the likely effect on lighting behavior?
• If the first fixture begins at address 2 and each device uses 3 slots, what is the end address of the fifth fixture?
• Which diagnostic equipment is BEST to use for troubleshooting an SCR dimmer system?
• Which method should be used to create a low-hanging fog effect on stage?
• What is a common symptom of a failing extension cord under load?
• What is the purpose of a GFCI on stage circuits?
• In a three-point truss weight distribution with Center (C) 1100 lb, Stage Right (SR) 700 lb, and Stage Left (SL) 310 lb, which point carries the heaviest load?
• In DMX lighting control, what does the term 'universe' refer to?
• What is the voltage rating commonly associated with SJOOW stage power cables?
• What is the available service type described for the building in the scenario?
• Which device protects the lighting control system from overvoltage on the DMX cable?
• Which device is used to provide access to splices and to route conductors around obstacles, and is used to join runs safely?
• Most chain motors designed for the U.S. and Canada will correctly operate on what voltages?
• After a performance, an entertainment electrician encounters an overheated connector in a long run of cables. Which is the BEST course of action?
• A rig entirely using 208V HMI fixtures has branch circuit breakers that run extremely hot beyond their rating. What is the most likely cause?
• In a lighting shop order, what item should be prioritized to ensure stock is available for install and maintenance?
• An entertainment electrician has 2-20K Fresnels (240V) on an elevated lighting platform. Assuming a power factor of 0.8 on the generator rating, which minimum generator size is required to power the luminaries?
• Which instrument should an entertainment electrician use to verify that the insulation on a feeder cable complies with NEC/CEC standards?