Here's my attempt to provide an answer for the correct time frame to use.
The right and short answer is:
It depends on your risk tolerance, profit expectations and the kind of broker that you use.
The time frame I will use personally is:
1 minute time frame. I will provide my reasons at the bottom of this post.
Firstly, you need to understand how your EA responds to your time frame that you set on the chart. Essentially, any EA will be triggered to perform an action at your specified time frame.
Let me give you an example.
If you set 5M as your time frame, at every 5 minutes, the EA will check if the market is trading against your position.
If it is NOT against your position, the EA does nothing.
If it is against your position (say you long the currency pair, but pair is going south), it then checks the distance between the current price against the previous order entry price. If this distance is equal or more than the Pip Step that you specify, then the EA will proceed to open a new order. The goal of doing this is to average out your orders, and therefore you will also notice that the Take Profit level is also adjusted to increase the chance of taking profit. As you know, prices don't move in a straight line. There is also an impulse and then a correction. And when prices move too quickly up, they usually correct themselves. This is also known as a pullback, retracement or reversal. The strategy of No Sleep EA is to take advantage of that.
I will use the 1 minute time frame because now I have control over the Pip Step and with the Pip Step Multiplier (PSM), I can exercise finer control over how the EA behaves. I now can increase the distances between each order at any time. Most martingale EAs do not have the features of No Sleep V3 and therefore require manual intervention. Typically, once a significant draw down occurs, I will logon to my VPS and increase the time frame of the chart. The reason for doing is again, is to increase the Pip Step which I do not have control over.
Oshaban saved the day by putting in this feature. Thank you once again
So if you are like me, who wants to have finer control over how the EA behaves, 1M is good.
If you are starting out and unsure how this work out, I would suggest a 5M or 15M with a small lot size. My advice is to open several demo accounts and running them simultaneously with the different variables. Observe them over a few months. Make certain tweaks and observe them again. That in my opinion, is the only way to learn and to grow as a trader and thinker.
In short, the perfect set file does not exist.