Man_AL32_eng_v9723_2.. - FF-Automation

Page 6 - 226/10/2001AutoLog 32 Instruction ManualThe pulse counters of the pulse counter board also require their own +5 V referencevoltage (from a separate power supply) or +24 V DC (from the power connector ofthe basic board), depending on the type of pulse sensors used.Expansion boards AL 32EX, AL 32EXA receive their +5 V supply voltage from thebasic board through the ribbon cable. The expansion boards further require a +15 Vsupply, which is generated on the expansion board from +24 V DC wired from thebasic board to the terminal strip of the expansion board.The expansion board AL32EXO receives + 5 V supply voltage from the basic board,the 24 VDC voltage for loads must be wired from external power supply unit.The +24 V DC supply voltage to the relay output boards is taken from an externalpower supply unit. The RE 16 board further requires a connection to the VDIODEterminal of the basic board.6.2.3 Digital inputsThe digital inputs are unisolated in AL32 PLC series. Only potential free contacts orNPN type inductive/capacitive sensors may be connected to PLC. The supplyvoltage for the NPN sensors is normally taken from PLC's terminals.It is recommendedto use twisted pair shielded cables in input wiring. The cabling should beinstalled separate from the 220/380 VAC power cabling. The cable shields may beconnected to logic ground only at one point, normally at the end on the PLCencloseure.If there is heavy electromagnetic disturbances, the PLC's inputs andoutputs can be isolated from field equipments with relays or with optoelectronicsmodules. Look at chapter 6.3.1.6.2.4 Digital outputsThe digital outputs are unisolated in AL32 PLC series. Only lowpowered 24 VDCcontrol relays, LED indicating lights or 24 volt indicating lights may be connected toPLC. The supply voltage for loads is taken from PLC's supply pwer unit.It isrecommended to use twisted pair shielded cables in output wiring. The cablingshould be installed separate from the 220/380 VAC power cabling. The cable shieldsmay be connected to logic ground only at one point, normally at the end on the PLCencloseure.If there is heavy electromagnetic disturbances, the PLC's inputs andoutputs can be isolated from field equipments with relays or with optoelectronicsmodules. Look at chapter 6.3.2.6.2.5 Analog inputs/outputsThe analog inputs and outputs are unisolated in AL32AN board. If active transducersare used, it should be checked that the output circuits of the transducers aregalvanically isolated from it’s supply voltages. If you can’t be sure of isolation, it isadvisable to furnish the transducer with an external galvanic isolator. The supplypower for passive transducer is normally taken from PLC’s power unit. Theimpedance of AL32AN PLC’s analog input is 2509FF-Automation Oy