The present study examined the capability of a real-time assessment routine to sort out the individual impact of three production systems on psychological activation as measured by the Stress-/Energy Inventory, Karolinska Sleepiness Scale, Borg's CR-10 Perceived Exertion scale, and the Swedish Occupational Fatigue Inventory. Sixteen women between the ages of 26 and 57 years (mean 43 years) rotated in a counterbalanced order between three production systems: A, B and C. The systems produced the same goods but clearly differed in degree of automation and ergonomic demands. The results show that work at the most automated production system, C, on average generated lower energy index scores and higher sleepiness scores compared to the oldest system, A. Clear weekly and diurnal patterns were found for most rating measures. To conclude, the increasing automation of the production systems is reflected in psychological activation by dampening feelings of positively valued high activity states and increased sleepiness. The expressions of a weekly and diurnal psychological activation, indicates that the subjects are able to unwind both during the weekend and after work, and suggest that the present method is suitable for studying the immediate psychological adaptation to the social and physical work environment.