Pages: [1]   Go Down
Author Topic: solid state spdt switch or equivalent?  (Read 655 times)
0 Members and 1 Guest are viewing this topic.
Offline Offline
Newbie
*
Karma: 0
Posts: 22
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

In my project i am using two wheelchair dc motors driving them with 50A driver board.
There are 4 inputs on a driver board for PWM signals, 2 for each motor, one to drive it forward & the other to reverse it.

right now i'm using 4 pwm outputs of arduino nano(3,9,10,11) cant use 5 & 6 since they are hooked up to another timer, with a frequency that makes audible noise on a motors.

Now i need to connect 2 hall sensors to measure motor rotation speed. for that i need to use interrupts, but on nano board i only have them on ports 2 & 3.
One of them (3) is already in use for pwm for the motor.

Is there a way to switch interrupt or pwm output to another leg?

I was also thinking to use two spdt relays to switch two pwm outputs of arduino between left & right inputs of driver board. Then I'll only need two pwm outputs & two digital signals to control relays.
But with relays I'll get noticeable clicking sound every time motor changes direction unless they'll bу some kind solid state relays. I never worked with any before & expecting that you can suggest some.

thank you 

Logged

Massachusetts, USA
Offline Offline
Tesla Member
***
Karma: 212
Posts: 8967
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

Perhaps if you had more information about the driver boards (make and model) it would be possible to use them with only one PWM input.
Logged

Send Bitcoin tips to: 1L3CTDoTgrXNA5WyF77uWqt4gUdye9mezN
Send Litecoin tips to : LVtpaq6JgJAZwvnVq3ftVeHafWkcpmuR1e

Offline Offline
Newbie
*
Karma: 0
Posts: 22
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

this is the board i'm using:
http://www.ebay.com/itm/300865229343?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
Logged

Massachusetts, USA
Offline Offline
Tesla Member
***
Karma: 212
Posts: 8967
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

Looks like it should work if you connect a PWM signal to each of the two "EN" pins.  Then you only need digital pins for RPWM and LPWM.

"Forward" would be RPWM=LOW, LPWM=HIGH.
"Reverse" would be RPWM=HIGH, LPWM=LOW.

You should probably set EN to LOW when you are switching between Forward and Reverse.

"Brake" would be RPWM, LPWM and EN all set to HIGH.  You can even feather the breaking by adjusting the PWM on EN.
Logged

Send Bitcoin tips to: 1L3CTDoTgrXNA5WyF77uWqt4gUdye9mezN
Send Litecoin tips to : LVtpaq6JgJAZwvnVq3ftVeHafWkcpmuR1e

Pages: [1]   Go Up
Jump to: