Site Logo Home
 
rOm
Quest
Glossary
 
Random
Page
Search
Site
Lush
Sim
Class
Subject
Images
 
Help
FAQ
Sign
Up
Log
In
GCSE     Timing     555     555 Astable     555 Monostable     >555 Motor Speed<     Mark Space    

Timing 555 Motor Speed


Site for Eduqas/WJEC - Go to the AQA site.

  GCSE    RC Timing  0 of 20    Question 407    555 Astable Duty Cycle 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set1 of 20    Question 392    555 Astable Facts 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set2 of 20    Question 394    555 Astable Facts 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set3 of 20    Question 389    555 Astable Formula 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set4 of 20    Question 390    555 Astable Formula 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set5 of 20    Question 1414    555 Astable Formula 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set6 of 20    Question 391    555 Astable Formula 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set7 of 20    Question 1415    555 Astable Frequency 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set8 of 20    Question 395    555 Astable Frequency 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set9 of 20    Question 396    555 Astable: High Pulse 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set10 of 20    Question 397    555 Astable: Low Pulse 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set11 of 20    Question 398    555 Internals 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set12 of 20    Question 399    555 Internals 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set13 of 20    Question 402    555 Internals 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set14 of 20    Question 403    555 Internals 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set15 of 20    Question 406    555 Monostable Calculation 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set16 of 20    Question 388    555 Monostable Facts 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set17 of 20    Question 404    555 Monostable Facts 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set18 of 20    Question 401    555 Monostable Period 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set19 of 20    Question 405    555 Monostable Period 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set20 of 20    Question 400    555 Timer Circuit 
Score 0/0 
Not attempted  
Last Answer  
Deadline not set  Questions 0 to 20   -->  View All  

Pulsed switching circuits can be quite tunefull.

If full power were applied to the motors when they were not spinning, the current would be so great that the power grid would fail. There might also be some wheel spin - on a train! and damage to the motors not to mention toppled grannies. Once the motors are running, there is Back EMF which reduces the current to a safer level. This is why the power has to be increased gradually.

This speed controller works in the same way.

Pulse Frequency Motor Speed Controller

This screen shot shows the astable (Blue) producing fixed width monostable pulses (Red) with about 20% duty cycle.

Pulse Frequency Motor Speed Controller Slow

This screen shot shows the astable (Blue) producing fixed width monostable pulses (Red) with about 90% duty cycle.

Pulse Frequency Motor Speed Control Fast

Adjust the potentiometer to change the frequency and vary the bulb brightness.

Yet Another Speed Controller

A thermistor in a voltage divider generates a temperature dependent voltage. This is amplified and used to control the 555 timer. The frequency and mark space ratio (duty cycle) vary depending on the control voltage. This makes a cooling fan run fast if it's hot or slowly if it's cool. The potentiometer is used to adjust the threshold temperature where the circuit starts to operate. This is a 12 Volt circuit (depending on the motor).

Thermistor Fan Speed Control with Pulse Width Modulation

Subject Name     Level     Topic Name     Question Heading     First Name Last Name Class ID     User ID    

fff
Home
<<<
ppw
Pg Up
<<
ppp
Up
<
|||

>|<
nnn
Down
>
nnw
Pg Down
>>
lll
End
>>>

Close
Escape
X

Q: qNum of last_q     Q ID: Question ID         Score: num correct/num attempts         Date Done    

 

Submit
Enter

 

Question Text

image url

 


Help Link

Add     Delete     Clone     Edit     Hardness

Help Text
Debug


 

 

 

Contact, Copyright, Cookies and Legalities: C Neil Bauers - reviseOmatic V4 - © 2016/17

Hosted at linode.com - London