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43 Cards in this Set
- Front
- Back
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Small amounts of _____ (off-state leakage) passes through an SSR even though the SSR is turned off. |
Current |
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An RC circuit is a circuit in which resistance and capacitance are uses to _____ the power |
Filter |
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Surge suppressors usually consist of |
A metal-oxide varsitor connected to the converter on the motor drive |
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What causes excessive heating in the motor when frequency is reduced |
Voltage not being reduced |
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Potentiometer |
Can be connected to a drive motor to drive terminals |
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Basic motor drives can contain |
30basic parameters |
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Most basic parameters |
Are the most conservative and most frequently used that create the least dangerous situations |
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Editing parameters |
Are those that can be used for specific applications |
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Display parameters |
Used to display operating, testing, installing, and troubleshooting |
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Pulse width modulation controls |
The amount of voltage output |
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Ramp stop |
Voltage is reduced as the motor decelarates |
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Electronic overload devices |
Sense changes in current and temperature |
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Voltage can be used to check |
Blowouts, improper grounding, contacts not closing, etc. |
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The power circuit is simplified by the motor drive |
By removing the reversing part |
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Motor torque is determined by |
Current |
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Soft stop |
Is the most common solid state stopping method |
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AC drives are the most common because |
It's easy to vary the speed |
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Motor speed on a DC motor is determined by |
Voltage |
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DC motor drives can provide dynamic braking through |
Connecting a resistor across the armature |
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S-Curve braking requires |
A transfer of energy from the rotating shaft back to the main power supply |
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The speed of an AC motor is controlled by |
The number of stator poles and the frequency of the power supply |
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Soft stopping is when |
Stopping time is doubled and the stop function is changed from ramp to S-curve slope |
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Converters are |
1 full wave rectifier, 1 wave bridge recitfiers, or 3 wave rectifiers |
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Current to the AC motor drive is limited by |
Conductors to the drive, fuse, circuit breaker sizes and transformers delivering power |
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An SSR consists of an |
Input circuit, a control circuit, and an output circuit |
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What is the most widely used relay? |
The Zero switching relay |
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Largest problem with SSRs |
Temp rise |
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What significant advantage does an SSR have over an EMR |
Response time |
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An SSR has a voltage drop of |
1.5 volts |
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A soft start is an |
Electronically operated switch which uses SSR components, and had overload protection |
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A typical solid state start consists of |
Both the start and run contactors connected |
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What is the most common solid state starting method |
Soft start |
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When does the input circuit deactivate |
When the dropout voltage is achieved |
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What does derating a motor do |
Reduce power |
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An analog switching relay |
Has a built in synchronizing circuit |
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Half waving is |
A phenomenon that happens when a relay doesn't stop because of voltage and current being out of phase |
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The most expensive motor starter install is |
Solid state |
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What starting method has the highest starting torque per amp |
Auto transformer method |
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What braking requires a method of transferring energy back to the motor shaft to the main supply |
Regenerative braking |
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What in am AC drive determines voltage level, frequency, and the amount of received current |
Inverters |
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What is soft stop |
Deceleration is doubled and stop is changed from slope to S-Curve |
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What measurements are taken to determine the condition of a motor |
Current |
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What circuit does a motor drive simplify |
Power |
