« previous next »
Pages: [1]

Author Topic: 8 VOLT PWM SIGNAL  (Read 13548 times)

CMS

  • Newbie
  • *
  • Posts: 18
  • I'm a llama!
    • View Profile
8 VOLT PWM SIGNAL
« on: May 07, 2007, 09:03:18 PM »
Hi

Can the T100MX ( opto inputs ) handle a 8 Volt PWM signal at 500 hz.      Is the 8 volt enought to trigger the input??

Thankyou
Logged

support

  • Global Moderator
  • Hero Member
  • *****
  • Posts: 3174
    • View Profile
    • Internet Programmable PLCs
Re:8 VOLT PWM SIGNAL
« Reply #1 on: May 08, 2007, 07:23:11 AM »
The spec is 9V minimum but 8 volt could be just about sufficient to turn on the T100MX+ optoisolated inputs. In the worst case scenario you can solder in parallel a resistor to the current limiting resistor onboard the PLC to increase the sensitivities.

500  Hz PWM signal is not a problem. You can use the PULSEWIDTH and PULSEPERIOD function to accurately measure the duty cycle of the PWM inputs.

Logged
Email: support@triplc.com
Tel: 1-877-TRI-PLCS

Dogface

  • Newbie
  • Posts: 33
  • Woof$
    • View Profile
Re:8 VOLT PWM SIGNAL
« Reply #2 on: May 08, 2007, 07:38:51 AM »
Another alternative is to use a high speed switching transistor.

8volt signal through a 500KOhm resistor into the base.  Collector tied into the PLC input. The emitter tied into ground.

Works like a charm.
Logged
Pages: [1]
« previous next »