3-23-1. Electrical wiringElectrical wiringIntroductionFor this instrument to operate, 15.6 to 42 V DC power supply is required to signals wiring.The electrical wiring of this instrument is described below as to the following items: Wiring cable connecting positions Dedicated cable connecting positions (detector and converter) Power source and load resistance Cable selection and cabling Grounding Wiring connection of power supply and analog current output Wiring connection for pulse output Wiring connection for contact output Wiring procedureNote) Do not connect commercial power directly to this instrument. Impressing commercialpower on this instrument causes unrecoverable damage to the internal measuring circuit.Power and load resistanceUse a direct current (15.6 to 42 V DC) for the power.Supply 50 V DC or over or 35 V AC or over causes unrecoverable damage to the instrument.The power ripple should be 1 V or less in peak-to-peak value.See that the load resistance of the loop wiring should within the operational range shown inFig. 3-1. with respect to the power supply voltage used.1164385250015.6 21.05 24 4221.05 < V < 30R = V–15.60.021830 < V < 42R = V–14.250.02383Supply voltage (V DC)1122Load resistance (Ω)Note) A load resistance of at least 250 Ω isneeded for communication with theSFC or HART® communicator.Fig. 3-1. Supply power voltage-load resistance characteristics
