## 3 Electrode Station Configuration
### General Remarks
* In field behaviour results, there is a similarity in the case of single-frame non-operation, among the 1 st, 2 nd, 5 th, and 6 th frames, as well as between the 3 rd and 4 th, through an appropriate mirroring consideration. However, when determining the absolute potentials, there is a slight variation since the integration is always carried out on the Ox semi-axis. From the study of the results for the region of Stachtoroi, the following emerges:
* The deviation at the extremes of the array (along the yOy\({}^{\prime}\) axis) reaches up to 24.7 m depending on the loading method (especially when the five frames are loaded consecutively), and along the xOx\({}^{\prime}\) axis, it reaches up to 36.18 m (especially when the five frames are loaded, except for one of the extreme ones, i.e., 1 st, 2 nd, 5 th, or 6 th). However, in the region of the non-operating frame, the corresponding electric field strength rises slightly over 2.5 V/m; therefore, no issues arise (regarding safety) when maintaining the frames, provided the diver has taken the appropriate measures. * The deviation in the maximum developing electric field strength of the electrode station compared to a single frame (20.03 V/m against 17.96 V/m, according to Table 11 in [2]) is of the order of 11.5%, which is significantly greater than those in the two previous configurations (19.73 V/m for the first configuration according to Table 14 in [2] and 19.08 V/m for the second configuration according to Table 1), despite the fact that the necessary distances are observed. * The critical zone of the dam extends beyond it by 30.8 m (with a crest width of 5 m and a suspension distance of at least 1 m) along the xOx\({}^{\prime}\) axis (perpendicular to the dam), which is slightly longer than that of the first configuration (30.3 m). * The critical zone of the dam extends beyond it by 41.4 m (i.e., 20.7 m on either side) along the yOy\({}^{\prime}\) axis (parallel to the dam axis) in the coastal area. Despite the fact that the initially estimated required length of the assumed electrode station is 42.0 m (along the yOy\({}^{\prime}\) axis), the corresponding actual required length is 91.4 m (from the results of the superposition model, according to Table 2), while the available length is only 50 m.
* The developed absolute potentials and the corresponding values of the electrode station resistance, with respect to remote earth, are quite worse (21.48 kV, 18.40 \(\Omega\)) compared to the initial configuration (17.30 kV and 14.82 \(\Omega\), according to Table 15 in [2]). * In field behaviour results, there is a similarity in the case of single-frame non-operation, among the 1 st, 2 nd, 5 th, and 6 th frames, as well as between the 3 rd and 4 th, through an appropriate mirroring consideration. However, when determining the absolute potentials, there is a slight variation since the integration is always carried out on the Ox semi-axis. Summing up, the third configuration presents more unfavourable field results compared to the previous configurations, which do not create a problem for the diver during maintenance, with the benefit of a more compact positioning of the electrode frames in a limited pond. An additional disadvantage is the more complex station structure due to the second row of frames at a distance from the dam. Figure 23: (**a**) Electric field strength, (**b**) area of electric field strength; blue denotes values lower and yellow indicates values higher than the limit of 1.25 V/m, with linear current sources, regarding an electrode station with the 3 rd configuration, in the area of Korakia (\(\rho_{S}=\infty\), without dam, \(\rho_{w}=0.25\)\(\Omega\cdot\)m, \(\ell_{p}=0.50\) m, \(d_{p}=11.00\) m, \(s_{c}=10.00\) m, \(L=2.13\) m, \(\theta_{g}=248^{\circ}\)), \(J_{mt,st}=22\) A/m\({}^{2}\) (5-frame operation, excepting no. 6; steady state).