Designing PCB for Relay to control the 240 VAC power applicances

[NishantSood]

I have already designed the PCB for the 240 VAC controlling purpose but i'm not getting the WIDTH of the TRACKS in PCB to keep the system ON safely and ensure that PCB tracks dsn't get worn out with 240 VAC , i'm using the 5pin SPDT relay on board. here is the PCB, i have already made the tracks(0.05 inch) heavy than the normal ones which are 0.02 inch

here is the PCB pic made with CAD for EDA's:

**broken link removed**

and the Real World look

**broken link removed**

I WANT TO KNOW WHETHER ANY CHANGES IN TERMS OF TRACK THICKNESS ARE NEEDED OR WILL IT SUFFICE LIKE THIS ONLY?​

 

[pranam77]

Just using 240 volts the tracks will not be damaged. It all depend on the laod you drive. Track thickness is mandatory only if the load on it exceed the load capacity of the width of the tracks. Untill some milli-ampere's are run on the input side, no modifications are required. On the relay contacts side, it all depends on what load you drive with the relay contacts.

 

[tyildizak]

Hi, The red track below would be safer:
**broken link removed**

 

[swordfish01]

Hi,

As pranam77 said, the width of the track does not depend on the voltage applied, but on the current running over the track.
As a rough estimate you could have a look at those graphs: Multi PCB Leiterplatten Technik Design Regeln - Leiterbahn / Strombelastbarkeit / Temperatur .
The text is in German, but the graphs should be language independent . As you see there, the minimum track width depends on you copper thickness and the maximum temperature raise you want to/can allow.

You could also calculate the temperature raise in your tracks by various methods, or some online calculators like this one: The CircuitCalculator.com Blog » PCB Trace Width Calculator .

When you talk about 230V, you should also watch the necessary spacings between the tracks in you 230V domain, as well as from the 230V domain to your control circuits. Normally a few millimeters should do the job, but if you design for a commercial application you might be required to leave much more space (IPC-2221 PCB Trace Clearance)

Regards,
Andreas