Below we will include the info direct from the manufacturers website in regards to this particular piece. The control system on this unique self propelled barge includes four independent PMC Z-MaC systems (Azimuth Marine Control). This arrangement isolates failures associated with one drive from affecting other drives. All electronic propulsion control signals from the bridge stations are fed to the control cabinets located in the “A” and “B” end engine rooms. The Z-MaC ensures maximum propulsion versatility and includes necessary logic and interlocks. It also contains user selectable set points for system response, timing and rpm limits. The electric signals from the Z-MaC are fed to speed, gear and steering servos for each drive. The steering control servo provided with the water jet drive accepts -10 to + 10 VDC for CW and CCW rotation commands. This ensures the display meters function independent of the controls. The PMC propulsion control system includes two control stations designed for outdoor use. Both stations are identical and contain the following. Four PMC Type 8161 Azimuth Display Meters. Four Drive fault indicator lights. One Purge pushbutton for simultaneous activation of all drive reverse clutches. Station transfer pushbutton and status indicator lights. Dimming, test, silence and internal horn.