The system of EA trade without logic, and for me the elect are undoubtedly the Martingale Strategy, the issue here is the setup that comes by default, we increase the  pipstep 1 to 50pips and pipstep 2 with 100 pips, it is that we have a freedom of 250 pips a day in the great moments of volatility without put the account at risk, for not passing the 20% risk margin used, which is a good concept to trade in consistency day after day, without manual intervention, making a daily profit of 5-10%, which is not bad since this system. So the EA trade with low risk, in a business already very risky. 

Before asking any questions, I would like to know how long have u used this strategy?

I am asking this because SL and TP for these systems are usually defined after practicing different targets.

Yes you can also defines the SL and TP, but in my case, the EA are configured to use up to 20% risk margin on the amount invested and do not use SL. I've been using this system for over a year.

Yes there r systems where instead of SL, opposite signal is used to close a trade.

We have to be very sure about the time when we trade because it makes huge difference. This is why I follow the trend tightly, if I am not sure or if there are any doubts, I never trade. I feel very comfortable under OctaFX broker especially with their wide range of features and facilities that counts for lowest possible spreads at 0.1 pips for all major pairs, zero balance protection and we can even use their day to day market updates to know about situations easily.