[fysnh]

1. Which one of the following device using the analog signal?
A. VFD. B. start/stop button. C. Occupancy sensor


2.how to reduce VFD harmonic current?
A.rectifiler b.lower the load
C.raise the load
D. Change the power factor


3.split phase Dc motor ,when centrifugal switch cannot close ,what will happen?
A.motor not start ,but hum
B.motor running at low speed.
C. Run winding will overheat
D.the start windings will bum out


4.split phase DC motor ,when centrifugal switch is stuck close by corrosion on the slides of switch, what will this probably cause?
A.the motor may not start,but hum
B.the motor will not reach full speed
C.the run windings will burn out
D. The start windings will bum out


5.a new overload relay keeps tripping ,what should be done?
A.replace the relay
B. adjust the relay
C.adjust voltage
D. Replace over load with VFD




Thanks

 

[chicken steve]

Bddab


~cs~

 

[Roger]

What were your answers and how did you arrive at those answers?

Roger

 

[ponyboy]

I'm not just gonna give answers but does anyone else think #5 is a piss poor question?

 

[fysnh]

1

What were your answers?

1.A2.A3.A 5.d

Just guess. ,I know nothing about VFD

 

[fysnh]

Bddab


~cs~

U sure?

 

[FrunkSlammer]

on and off (stop and stop) is a digital signal, like binary 1 or 0.

 

[fysnh]

What were your answers and how did you arrive at those answers?

Roger

I did the exam. ,I failed

 

[fysnh]

I'm not just gonna give answers but does anyone else think #5 is a piss poor question?

If u know it, please help

 

[fysnh]

on and off (stop and stop) is a digital signal, like binary 1 or 0.

VFD is correct?

 

[ponyboy]

If u know it, please help

I know them all. The most helpful thing you could do for yourself is read the chapters and see what you missed

 

[fysnh]

I know them all. The most helpful thing you could do for yourself is read the chapters and see what you missed

My code don't have the answer , my code doesn't even mention VFD .

 

[fysnh]

I know them all. The most helpful thing you could do for yourself is read the chapters and see what you missed

Thanks anyway

 

[Tsmil]

Which exam? C of Q?

 

[tryme]

B, b, d, a, b

 

[tryme]

What were your answers and how did you arrive at those answers?

Roger

Lots like that on the C of Q. It's a way of thinking. Simplify your mind and become one with the question.

 

[fysnh]

B, b, d, a, b

Thanks

 

[tryme]

on and off (stop and stop) is a digital signal, like binary 1 or 0.

*facepalm*

 

[ablyss]

For first question I'd guess the occupancy sensor is analog and I'll explain why. Digital is like FrunkSlammer said, 1s and 0s. The occupancy even though runs off 120v AC, the sensor part uses analog detection, ie. Infrared.

2. Lowering the load is the only reasonable answer.
3. No idea
4. No idea
5. Adjust Relay

 

[fysnh]

For first question I'd guess the occupancy sensor is analog and I'll explain why. Digital is like FrunkSlammer said, 1s and 0s. The occupancy even though runs off 120v AC, the sensor part uses analog detection, ie. Infrared.

2. Lowering the load is the only reasonable answer.
3. No idea
4. No idea
5. Adjust Relay

thanks