User manual HANNA INSTRUMENTS HI 8931

[. . . ] Instruction Manual HI 8931 · HI 8936 Series HI 943500 Series Conductivity Process Controllers and Transmitters www. hannainst. com Dear Customer, Thank you for choosing a HANNA instruments® product. Please read this instruction manual carefully before using the instrument. This manual will provide you with all the necessary information for correct use of the instruments, as well as a precise idea of thier versatility in a wide range of applications. If you need additional technical information, do not hesitate to e-mail us at tech@hannainst. com directives. [. . . ] · The HI 7638 process conductivity probe is also supplied with a 3 m (10') cable. The 6-core cable of this probe is connected to the HI 8936 process conductivity transmitter as shown. The DIN connector has to be removed when this probe is used in conjunction with an HI 8936 transmitter. See page 24 for the proper connection scheme. FOR HI 943500 ONLY Ensure that the HI 7638 conductivity probe is connected to the meter securely by aligning the pins with the socket, pushing the plug in and tightening the threaded ring. · The HI 7635 conductivity probe is supplied with a 3 m (10') cable. The 6-core cable of the probe is connected to the HI 8936 transmitter as shown. The connections are color coded for an easy installation. See page 24 for the proper connection scheme. 26 27 OPERATING INFORMATION All parameters are set through the front panel keys and trimmers. When any key is pressed, the corresponding LED lights up to indicate that the function is active. Make sure that the conductivity meter, transmitter and probe are calibrated before taking measurements (see pages 31, 35 and 39 for calibration procedures). Below Setpoint Control Operation Short the "SET SELECT" and "COM" connectors with a jumper wire. The set contact relay will close if the measured value is lower than the setpoint value, and the "SET ON" LED will light up. COM SET SELECT SET POINT To set the working point of the controller, press the SET key. The display will indicate the current set value. ALARM Press the "AL" key and the display will show the set tolerance for the alarm. Use a small screwdriver to adjust the COARSE and FINE trimmers until the desired value is displayed. Above Setpoint Control Operation Leave the "SET SELECT" and "COM" connectors open. The set contacts relay will close if the measured value is higher than the setpoint value, and the "SET ON" LED will light up. COM SET SELECT Use a small screwdriver to adjust the "AL" trimmer until the desired tolerance is displayed. For example, if the set value is 200 S/cm and a Alarm of 50 S/cm is set, an alarm will be activated every time the measured value is higher than 250 S/cm or lower than 150 S/cm. When an alarm occurs, the "ALARM" LED lights up. 28 29 The alarm contacts of HI 8931 and HI 943500 remain closed during normal operation. If the measured conductivity level is not within the tolerance of the set value, the alarm contact will be open. CALIBRATION PROCEDURE OF HI 8931 & HI 8936 WITH HI 7635 Material needed: · HI 7635 conductivity probe · HI 8931 conductivity controller · HI 8936 conductivity transmitter · A 20 mA f. s. ammeter (for transmitters without LCD) · A reference conductivity meter with automatic temperature compensation accurately calibrated (e. g. HI 8733). TAKING MEASUREMENTS WITH HI 8931 AND HI 943500 After setting the working point and alarm value, press the "MEASURE" key. The actual conductivity value of the test solution will be displayed. PROCEDURE · Connect the HI 7635 probe to the H I8936 transmitter (see page 24 for details). · Connect the HI 8936 transmitter to the H I8931 controller (see page 25 for details). · Connect the HI 8931 controller to the mains (see page 25 for details). Before proceeding with the calibration, make sure that the meter is in measureMEA ment mode ("MEASURE" LED is on) and SURE not in set mode. · Connect the ammeter to the HI 8936 transmitter to monitor the signal current (see below picture). TAKING MEASUREMENTS WITH HI 8936AL, HI 8936BL, HI 8936CL, HI 8936DL The conductivity transmitters with LCD will always display the measurement value when connected to the HI 8931 controllers or a power supply. 30 31 · Ensure that the HI 7635 conductivity probe is dry. · When the power is on, the ammeter should read "4. 0 mA". [. . . ] Operation of these instruments in residential area could cause unacceptable interferences to radio and TV equipments, requiring the operator to take all necessary steps to correct interferences. The trimmers are sensitive to electrostatic discharges. It is recommended to use antistatic screwdrivers. Unplug the instrument from the power supply before replacing the fuse. [. . . ]