Hello again,

                   here are some more thoughts. Apologies if they are obvious to you already.


1. It is important to fully understand what the new designed board is expected to do. Get a written specification first.


2. Are there any space constraints? Will it have to fit in a restricted space?


3. What operating conditions will it experience, vibration such as on a vehicle where relays may be made to drop out, or in cold or hot conditions. Will it be reliable at minus 15 degrees C or plus 85 degrees C?


4. Will it be powered by your power supply or one already available? Can it cope with a ten percent drop in supply Voltage or a 15 per cent increase in supply Voltage. Can it cope with noise from other sources? If battery operated will it work for the time required on one battery or battery charge?


5.Does it work reliably under all expected operating conditions of supply Voltage and frequency? Is it thoroughly tested?


I had to ensure safe earthng of big mobile military stuff on trailers once. At the tester's location a large adjustable mains generator was brought in to supply low and high supply Voltages at various different frequencies. The tests were thorough. Most stuff passed but some failed.


When you supply a prototype you must supply exact details of supply Voltage (A.C. or D.C), and current required (Amps or Watts consumed) and other essential info. so that if it is tested when you are not present, all will be well. State everything clearly on a user's guide sheet. 


Velleman kits are examples of well designed, tried and tested electronic circuits. Stocked by C.P.C. (CPC Farnell) and others like Amazon. The components are of reliable good quality too.


Just some thoughts,


Good luck,


Z.

Hello again,

                   here are some more thoughts. Apologies if they are obvious to you already.


1. It is important to fully understand what the new designed board is expected to do. Get a written specification first.


2. Are there any space constraints? Will it have to fit in a restricted space?


3. What operating conditions will it experience, vibration such as on a vehicle where relays may be made to drop out, or in cold or hot conditions. Will it be reliable at minus 15 degrees C or plus 85 degrees C?


4. Will it be powered by your power supply or one already available? Can it cope with a ten percent drop in supply Voltage or a 15 per cent increase in supply Voltage. Can it cope with noise from other sources? If battery operated will it work for the time required on one battery or battery charge?


5.Does it work reliably under all expected operating conditions of supply Voltage and frequency? Is it thoroughly tested?


I had to ensure safe earthng of big mobile military stuff on trailers once. At the tester's location a large adjustable mains generator was brought in to supply low and high supply Voltages at various different frequencies. The tests were thorough. Most stuff passed but some failed.


When you supply a prototype you must supply exact details of supply Voltage (A.C. or D.C), and current required (Amps or Watts consumed) and other essential info. so that if it is tested when you are not present, all will be well. State everything clearly on a user's guide sheet. 


Velleman kits are examples of well designed, tried and tested electronic circuits. Stocked by C.P.C. (CPC Farnell) and others like Amazon. The components are of reliable good quality too.


Just some thoughts,


Good luck,


Z.