CPU 1518-4 PN/DP ODK (6ES7518-4AP00-3AB0)28 Manual, 09/2016, A5E35681108-AAConnecting up 3This section provides information on the terminal assignment of the individual interfaces andthe block diagram of the CPU 1518-4 PN/DP ODK.24 V DC supply voltage (X80)The connector for the power supply is plugged in when the CPU ships from the factory.The following table shows the pin assignment for a 24 V DC power supply.① +24 V DC of the supply voltage② Ground of the supply voltage③ Ground of the supply voltage for loop-through (maximum of 10 A permitted)④ +24 V DC of the supply voltage for loop-through (maximum of 10 A permitted)⑤ Spring opener (one spring opener per terminal)Bridged internally:① and ④② and ③Figure 3-1 Supply voltage connectionIf the CPU is supplied by a system power supply, it is not necessary to connect the 24 Vsupply.