Motor Control 1 Flashcards
Which of the following electrical industry pioneers invented the first practical AC motor?
Nikola Tesla
A ? actuates manually-operated pilot devices..
Human Operator
Automatically operated input devices are switches triggered by a change in a ? parameter, such as liquid level, pressure, fluid flow, and material temperature.
Process
A relay is an electromagnetically controlled ? .
Switch
The term interposing relay is used to describe a relay which enables the energy in a ? circuit to be switched by the ? circuit in a control system.
High-powered / low-powered
The sealed current called ? implies that relays and solenoids are pulled in.
steady-state current
When the contactor and ? are combined into a single device or separate devices that are wired together, the combination is a motor starter.
Overload
Knife switch improvements including insulated handles and spring loaded blades mounted inside steel enclosures evolved into the modern ? .
Disconnect switch
Overloads offer protection from excessive current flow to the switched load. When the contactor and overload are combined, the combination is a ? .
motor starter
The power poles in the starter carry the motor current while other contacts, called ? are used for the control circuit.
auxiliary contacts
An ? timer is a device with a preset time period between energizing the timer or applying the input signal and the action of the timer output contacts. During the timing period, no change occurs in the timer output contacts.
On-Delay
Once initiated, ? contacts change state after a set time period has passed. Once the time has passed, all normally open timed contacts close and all normally closed timed contacts open.
DOE
An ? timer is a device with a preset time period that starts after the input signal is removed. The timer output contacts change when the input signal or external trigger is applied, and the contacts remain in the changed state until after the timing period.
Off-Delay
The off-delay timer function is also called a ?
DODE
Assume a DOE timer is configured with one normally closed contact with a time-delay of 30 seconds. What is the position of the contact prior to power being applied to the coil?
Closed
Assume a DOE timer is configured with one normally closed contact with a time-delay of 30 seconds. What is the position of the contact immediately after power is applied to the coil?
Closed
Assume a DOE timer is configured with one normally closed contact with a time-delay of 30 seconds. What is the position of the contact 30 seconds after power is applied to the coil?
Open
Assume a DOE timer is configured with one normally closed contact with a time-delay of 30 seconds. What is the position of the contact as soon as power is removed from the coil?
Closed
Which timer is appropriate for keeping a motor starter energized after power is removed from the timer’s power input?
DODE
What is the abbreviation for delay on de-energize?
DODE
Assume a DODE dashpot timer is configured with one normally closed contact with a time delay of 30 seconds. What is the position of the contact prior to power being applied to the coil?
Closed
Assume a DODE dashpot timer is configured with one normally closed contact with a time delay of 30 seconds. What is the position of the contact immediately after power is applied to the coil?
Open
Assume a DODE dashpot timer is configured with one normally closed contact with a time delay of 30 seconds. What is the position of the contact 20 seconds after power is removed from the coil?
Open
Assume a DODE dashpot timer is configured with one normally closed contact with a time delay of 30 seconds. What is the position of the contact 30 seconds after power is removed from the coil?
Closed
Assume a DODE solid-state timer is configured with one normally open contact with a time delay of 10 seconds. What is the position of the contact prior to the input of the external trigger switch?
Open
Assume a DODE solid-state timer is configured with one normally open contact with a time delay of 10 seconds. What is the position of the contact immediately after an input signal is received from the external trigger?
Closed
Assume a DODE solid-state timer is configured with one normally open contact with a time delay of 10 seconds. What is the position of the contact immediately after the input signal is removed from the external trigger?
Closed
Assume a DODE solid-state timer is configured with one normally open contact with a time delay of 10 seconds. What is the position of the contact 10 seconds after the input signal is removed from the external trigger?
Open
A conveyor may be required to run for a period of time after a stop circuit is activated to assure the product is cleared from the conveyor, this would be an application for which type of timing relay?
DODE
After a start signal is received to start a pump motor, a time delay is required to allow time for pre-lube to the pump. This would be an application for which type of timing relay?
DOE
Which type(s) of motor control drawing(s) show the physical location of components in a circuit?
I. Ladder diagrams
II. Pictorial diagrams
III. Schematics
IV. Wiring diagrams
II. and IV.
Schematic diagrams use graphic symbols to show ? between components and ? of an electrical circuit.
Connections / Functions
Ladder diagrams show physical placements between the various components in a motor control drawing.
False
What is the most widely used type of drawing for control circuit analysis?
Ladder Diagram
Each horizontal line in a ladder diagram is identified as a ? .
Rung`
