Signal amplifier GENERAL CHACTERISTICS The VNR2300 control unit was designed as low cost interface for conductive level probes. These electronic units are used to control liquids that have a minimum electrical conductivity of 10 pS. The system is based on measurement of the conductivity of the liquid to be controlled and works with low potential and with alternating currents, in order to avoid the incrustation of the electrodes and / or perforation of the tank normally caused by the use of direct currents, which cause a galvanic action on materials. The contact of the electrode with the liquid under control determines the actuation of a relay inside the control unit and it is possible to drive any alarm system and / or actuator. By using multiple probes and multiple control units, appropriately connected, a system of dosage and safety can be realized. • Adjustable sensitivity from 10pS. • Double relay output. • DIN rail mounting. Power supply Power consumption Input signal Power supply to probes Output relay Sensitivity range Sensitivity adjustment Operating temperature Housing Degree of protection Mounting Dimensions (mm) Electrical connection 24 Vac 50/60 Hz 230 Vac on request 5 VA From conductive probes 22 Vac 2 x SPDT 250Vac 5A 10 - 250 pS Factory setting 60pS Side trimmer -20° +50° C ABS IP 40 DIN rail 60 x 100 x 45 11 poles terminal board SENSITIVITY ADJUSTEMENT TYPICAL WIRING MIN./MAX. LEVEL ALARM Tank ground MIN. level probe MAX. level probe N.O. N.C. COM. N.O. N.C. COM. CONTROL AND ADJUSTMENT Control. Disconnect the electrodes leads from the terminal board (terminals 5 and 6). Short circuit terminals 5 and 6 of the terminal board, in these conditions, the relays must switch on. Sensitivity adjustment. The unit is supplied with a factory setting of 60 pS. Submerge the electrodes in the liquid under control, turn the side trimmer to obtain the switching of the relays. Type Tab.1 Sensitivity Tab.1 Power supply We reserve the right to change the data without notice -Level- flow -ffBSSUIB Temperature-Bedim www.valco.it