LCD error. letters are shifting each water valve is ON

[wishesdoom]

hello friends. sorry for bad english.

i have a system controled by 16f877 and output relays. when 24V water relay is active, letters on 4x20 LCD are shifting one character to left. sometimes also system is reset.

if i connect the valve directly to the 230 v, the valve is no connection to the board or anything else; i have the same problem. it is possible transmissed an electronic magnetic area. how can i solve this problem. thank you.

[mackrackit]

Is the board running from batteries or mains? Is the board grounded?

[wishesdoom]

yes all the -'s and grounds are together and grounded. board running power supply 230v to 24v.

[mackrackit]

What is the power supply like? Do you have plenty of capacitors?
Maybe post the schematic schematic.

[wishesdoom]

here is power supply:
http://static4.tme.eu/katalog_pics/8...b5/dr-4524.jpg

the pic and LCD is feeded by two 78l05cv

[mackrackit]

it is possible transmissed an electronic magnetic area. how can i solve this problem.

Yes, it is possible. I sometimes have this problem around welders and plasma cutters. The solutions range from good grounding to putting the MCU in a metal enclosure ( think Faraday cage ).

[wishesdoom]

thank you friend for your help. i am working on it.

[aliciaDJones]

LCD ": This full-fledged, large-character liquid crystal display per-Vides you. Water budgeting: Each program can be independently adjusted to more or less water power the script is the problem drive, and all other operational water valve.

[aliciaDJones]

I don't found such type of error in the LCD...