User manual HANNA INSTRUMENTS HI 7871

[. . . ] If service is required, contact the dealer from whom you purchased the instrument. If under warranty, report the model number, date of purchase, serial number and the nature of the failure. If the repair is not covered by the warranty, you will be notified of the charges incurred. If the instrument is to be returned to Hanna Instruments, first obtain a Returned Goods Authorization Number from the Customer Service department and then send it with shipment costs prepaid. [. . . ] A complete system should consist of: · HI 7871 or HI 7873 level controller; · HI 7874 transmitter and sensor holder; · HI 7164 11-pin connector; · 3 or 4 measuring bars. The level transmitter is basically a molded electrode holder with 4 sockets to screw in the level sensors. The longest bar has to be the common electrode and connected to the COM port. The remaining electrodes can be connected in any sequence, after cutting them to the required lengths. HI 7874 contains the completely resinated amplifier circuit and the 2-wire terminal board. It also comes with a mounting bracket for quick and easy installation. HI 7874 uses stainless steel measuring bars and employs 9V peak to peak A. C. It can be used in liquids with conductivity greater than 10 µS/cm (µmho/cm). HI 7871 requires only 3 electrodes, whereas HI 7873 needs 4. HI 7871 is a basic high and low level controller. HI 7873 has an overflow alarm control as an additional feature. 76mm 3" 95mm MIN 3. 74" Adjustable brackets (supplied) allow the controller to slide into the cutout and hold the unit in place. 95 mm (3. 74") is the minimum space required to install the controller with the cables connected. FUNCTIONAL DESCRIPTION FRONT VIEW 1 2 3 REAR VIEW 4 1. OVER LED (HI 7873 only) indicates an overflow condition 2. 11-pin Socket SPECIFICATIONS HI 7871 HI 7873 Level Adjustment High, Low High, Low, Over Level Indication High, Low High, Low, Over Transmission 300 m (990') max Socket/Connector 11-pin connector Sensing Bars* 3 4 Transmitter* HI 7874 Output Contact One, 2A/220V Two, 2A/220V relay for up to relays for up to 1, 000, 000 closures 1, 000, 000 closures Power Supply 110/115V or 220/240V ­50/60 Hz Environment 0 to 50°C (32 to 122°F) Max. 85% RH non-condensing Dimensions 79 x 49 x 95 mm (3. 1 x 1. 9 x 3. 7") Weight 130 g (4. 6 oz. ) * Not included with HI 7871/7873. The common terminal (#4) and #3 can also be connected to a device to indicate a "full tank" state. · With HI 7873, connect terminals #10 and #11 to an alarm for monitoring Over Flow condition. CONNECTIONS · Remove the 11-pin connector from the rear of the level controller. · Remove the cover of HI 7874 (bar holder) and connect a 2-wire cable from #8 to positive (+) and #9 to negative (­) terminals of the holder. · Connect a 2-wire power cable to terminals #2 and #7 (no ground connection). · Screw the longest bar to the hole marked as COMM. This bar will be used as the reference electrode. Screw the other measuring bars into the remaining sockets in any order. The bars should be cut to the required lengths for low, high and over. [. . . ] If the LOW LED remains lit but the pump/electrovalve is not activated, it indicates an open circuit. · When liquid level reaches the high (2nd) bar, HIGH LED turns on and the output contact (#5) opens (pump/ electrovalve disactivated) while #3 & #4 close: A short circuit will instead give a HIGH LED indication. Note: It takes about 8 seconds for the controller to activate the relay from when an alarm condition occurs. · With HI 7873, if after reaching HIGH level, liquid level continues to rise and reaches the 3rd bar, the alarm contacts close and the OVER LED comes on: ACCESSORIES HI 7164 HI 7875/P 11-pin connector Sensing bars, 5 pcs, 50 cm long (1. 5') Note: The sensing bars are made in such a way that they can be screwed into each other to provide any required length. It is recommended to keep the bars separate with a non-conductive material such as plastic to ensure they do not touch each other, specially in deep tanks. CE DECLARATION OF CONFORMITY Recommendations for Users Before using these products, make sure that they are entirely suitable for the environment in which they are used. Operation of these instruments in residential areas could cause unacceptable interferences to radio and TV equipment. Any variation introduced by the user to the supplied equipment may degrade the instrument's EMC performance. [. . . ]