Author Topic: T100MD100 with 12 volt power  (Read 9324 times)

cdenk

  • Full Member
  • Posts: 161
  • newbie
    • View Profile
T100MD100 with 12 volt power
« on: March 15, 2005, 02:46:45 PM »
With T100MD100, MD-EXP4040, and MD-HMI, are there any issues with usung 12 volt power. On the MD-HMI, the 15 watt resistor for backlight, should it be a different value?

The application is controlling a tri-fuel standby generator, and the backup PLC power will be the generator's 12 volt battery. Will brief interuptions in the PLC power , like when a relay (coil from 120 volt power) drops to the battery supply. The brief period of inactivity is not an issue as long as the PLC at worst resets and then continues. Is there a better way to handle the power change over?

support

  • Global Moderator
  • Hero Member
  • *****
  • Posts: 3174
    • View Profile
    • Internet Programmable PLCs
Re:T100MD100 with 12 volt power
« Reply #1 on: March 15, 2005, 07:34:06 PM »
You can use the T100MD+ PLC with  EXP4040 at 12V DC. The 150 ohm resistor provided for the backlight can still be used although the brightness is lower. If you want a higher brightness you can use a lower resistance 5W resistor (say 75 ohm) with it.

Brief power interruption will likely to reset the PLC. It will be better to get some kind of small backup battery or charge tank (big capacitor) for the CPU power and this should be separate from the main battery but are charged regularly.
Email: support@triplc.com
Tel: 1-877-TRI-PLCS