not easy but a must. whatever u see in control drawing consists of NO , NC, relays,contactors and its ferul no:s. for numbering of relays and contactors see inside the panel where debvice is mounrted. it will be denoted by 86, 74, K55 etc. just see in the dawing and locate where the device is and whatever contacts (N0 or NC) in the drawing will be of opposite status when it is energised.