Term
| How many hot legs in a single phase system? |
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Definition
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Term
| What is the voltage from neutral to hot in a single phase system? |
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Definition
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Term
| What is the voltage across hot legs in a single phase system? |
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Definition
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Term
| How many wires in a single phase system? |
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Definition
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Term
| What are the standard wire colors in a single phase system? |
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Definition
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Term
| How many hot legs in a three phase system? |
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Definition
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Term
| What is the voltage from neutral to hot in a three phase system? |
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Definition
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Term
| What is the voltage across hot legs in a three phase system? |
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Definition
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Term
| How many wires in a three phase system? |
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Definition
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Term
| What are the standard wire colors in a three phase system? |
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Definition
| Green, White, Black, Red, Blue |
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Term
| What do circuit breakers do? |
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Definition
Protects circuit during fault situation
Cut power when current is too high
Overloading of a circuit
Shorting a circuit
Power Surge |
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Term
| How does a magnetic circuit breaker work? |
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Definition
| A magnetic circuit breaker works uses an electromagnet that increases in strength as the current rises until it reaches the set limit. |
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Term
| What are pig tails in a lighting system? |
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Definition
| Cables with bare wire at one end and connectors on the other that attach to the load side lug nuts in a disconnect box. |
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Term
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Definition
A conductor which carries a large block of power from the service
equipment to a power distribution panel where the block power is broken down into smaller circuits. |
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Term
| What are the standard gauges of feeder cable? |
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Definition
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Term
| What is the standard phase distribution in a dimmer rack? |
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Definition
Three hot legs are distributed to different dimmers.
1 Phase to dimmers 1 and 2
2 Phase to dimmers 3 and 4
3 Phase to dimmers 5 and 6 |
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Term
| What styles of racks do dimmers come in? |
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Definition
Portable Racks
Touring Racks
Installed Racks |
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Term
| What are standard rack configuration sizes? |
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Definition
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Term
| What are standard dimmer power sizes? |
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Definition
Dimmer Power
2.4k rated for 2400w = 24x1.2k
1.2k rated for 1200w = 96x2.4k
Can also have 6k and 12k |
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Term
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Definition
| 96 dimmers and 2400 watts a piece |
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Term
| What is a hard wired circuit? |
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Definition
| A circuit wired directly into a dimmer |
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Term
| What does hard patch mean? |
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Definition
| Physically assign a circuit to a dimmer |
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Term
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Definition
A multi-cable is just that, one cable that contains multiple circuits; 6 or 12 individual circuits in one insulating jacket. The most common multi used is 6 circuitSocapex. The dimmer rack will have a Socapex female panel mount receptacle on the back and there will be a break-out or fan-out to 6 individual circuits on the fixture end. If the dimmer rack has individual receptacles then a fan-in is used on the dimmer side. A Socapex connector has 19 pins; 3 (hot neutral and ground) for each of the circuits and one un-used center pin. The outer circle of pins alternate hot and neutral while the inner circle provides the ground for each circuit.
•Portable dimming systems
•6 circuits in one cable
•Labeled by letter for the cable and number for the circuit
Circuit A-1, A-2, A-3…; Circuit D-1, D-2, D-3 |
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Term
| How are multi-cable circuits numbered? |
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Definition
1 is hot
2 is neutral
13 is ground |
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Term
| Why do we have to load balance? |
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Definition
Draw the same amperage off of each phase
80% of max per leg
Prevent overloading common return neutral
Prevent harmonics |
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Term
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Definition
| Don’t go higher then 80% of the total. |
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Term
| What is an SCR and what does it do? |
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Definition
| Silicon Control Rectifier - Silicon Controlled Rectifier; a solid-state unidirectional thyristor used in modern dimming systems. |
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Term
| How does a forward phase dimmer work? |
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Definition
| Switching on is delayed to dim lamp. |
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Term
| How does a reverse phase dimmer work? |
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Definition
| Switches off early to dim the lamp. |
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Term
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Definition
A ratio of light output to console fader level •Linear
-10% fader = 10% light output
•Logarithmic
-Can pre-heat filaments
-Most stress on filament when turning on
-Keeps current flowing through filament
-Longer lamp life |
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