Don't throw the one that isn't working away yet. I am investigating some Smart Effectors that passed initial testing but subsequently give 6 flashes.
EDIT: I have re-tested those. All of them work properly, except that some of them flash 6 times once or twice immediately after power up.
Note, it is normal to get 6 or 7 flashes once or twice while the circuitry stabilises. I will add this to the instructions. The version 1 effectors didn't do the same self-test, but many of them also needed a few additional seconds after power up before they responded to nozzle contact.
@dc42 any idea what the 6 flashes means? If I need to buy another smart effector it would be great if I could do that today
6 flashes means the same as 7 except the sensor output is out of tolerance the other way. It is quite common with the version 2 effector to see 6 or 7 flashes once or twice immediately after power up, and then to get the 2 flashes after the strain gauge amplifier has settled.