Push Button Quality test

Hi! I just want to ask if there is any way to test the quality of a push button? I have been using push buttons in my projects and I have encountered the same problem. With the continues use, it commonly lasted from 1yr to 2yrs. I have decided to used a different push button, but want to verify first its quality to assure its long term use. Is there anyway to test it? or any information in the datasheet that I need to consider? Thanks in advance.

Most manufacturers specify the number of operations. That should give you some idea of reliability. I don't think you want to waste your time testing them.

Hi,

or any information in the datasheet that I need to consider?

Click to expand...

..that's what a datasheet is for...

You should check all datasheet specifictions with your circuit situation.

A high current rated push button may fail earlier when you use it with low current.
A low current rated push button may fail earlier when you use it with high current.

Low current contacts are usually are made with thun, soft non oxidating contact material like Au. This ensures low impedance for a long time, but the thin contct material may be burnt away by high current sparks.
High current contacts are usually made with thick, hard, high temperature rated contact material like Be. This ensures that even high current sparks can not harm the contacts. But they tend to oxidate resulting in getting high impedance. Now the high current is indeed needed to burn away the oxide ... it is cleaning somehow the contact. But a low current doesn't have this cleaning effect.

So choose the push button according your circuit requirements. Maybe you even could adjust your circuit to meet the pusbutton's requirements. Often you find in a datasheet "minimum" voltage and current ratings.
If it says: min 5V, min 10mA ... then you should follow this recommendation.

Klaus

Many push buttons are indirectly actuated. Most are mounted on a PCB and they are operated indirectly. You must not

1. Exceed the force;
2. exceed the linear travel;
3. exceed the rated voltage and current (best to keep well below the rating).

Most push buttons don't live long because of excessive applied force.

For low current, I always use switches that have gold plated contacts (gold does not corrode) that cost the same as high current silver contacts (but silver corrodes if the current is low).