Operating instructions Capacitive level sensor KNQ 708 / 0 0 / 006
Contents Functions and features... 3 Electrical connection... 3 Installation... 4 Adjustment... 4 Locking / unlocking... 6 Operation... 7
Functions and features The capacitive level sensor monitors the level in tanks. It detects if medium is present or not and provides a switched signal. Adjustable to the respective medium via the teach element or via the programming input / function check output (FC output). 4 5 3 5 : : 3: 4: 5: Active area (teach element) Electrical connection (connector or connection cable) Sensing face (damping area) LEDs red, yellow, green 4 mounting holes Electrical connection Disconnect the power supply. Connect the unit as indicated on the type label. 3
Installation Fit the mounting adapter () onto the sensor (). The mounting adapter is an accessory and has to be ordered separately (E0879). Fix the sensor to the outer wall of the vessel using the fixing strap. The fixing strap is an accessory and has to be ordered separately (E0880). The sensor detects the medium through the tank wall. Suitable for dry media and liquids. Only for non-metallic tanks. Adjustment The sensor is adjusted via the teach element. To activate the teach element a metal object, e.g. a screwdriver, is necessary. Use this object to touch the active area. : Active area of the teach element 4
Empty adjustment The sensor is adjusted to the empty vessel. If it detects material, the switching signal changes. The green LED flashes. (= The unit is in the programming mode.) Activate the teach element for max. 5s * After a short time the green LED is lit continuously. (= The unit is set and in the operating mode.) Deactivate the teach element Full adjustment For most applications an empty adjustment is sufficient. In addition you can also carry out an adjustment to the medium (e.g. to obtain an optimum excess gain for special applications). The green LED first flashes slowly (approx. Hz), then more quickly (approx. Hz). (= The unit is in the programming mode.) Activate the teach element for about 5-0s * The green and the yellow LEDs are lit. (= The unit is set and in the operating mode.) Deactivate the teach element 5
*You can also lock/unlock the unit via pin (FC output) (wire programming). A signal on this input corresponds to the activation of the teach element. Type FPKG: (+UB) on pin. Type FNKG: (-UB) on pin. Programming via the teach element has priority over wire programming via pin (FC output). New programming or one in process via wire programming is blocked by actuating the teach element. The values saved for the empty adjustment are not overwritten by the full adjustment. You can repeat the full adjustment as often as you wish. After a new empty adjustment the switching thresholds are automatically reset; the values defined last are overwritten. If no adjustment is possible (e.g. "empty" signal and "full" signal are about the same), the red LED flashes after adjustment (in addition the function check output provides a Hz signal). Activate the teach element briefly (= acknowledgement), the unit changes to the operating mode with unchanged values. Repeat the adjustment (starting with step ) if you want to carry out another adjustment. Locking / unlocking The green LED first flashes slowly, then more quickly. After 0s it goes out, the unit is locked. Locking: Activate the teach element for min. 0s*. After 0 s all LEDs go out briefly. The unit is then unlocked and the LEDs indicate the current operating state. Unlocking: Activate the teach element for min. 0s*. 6
*You can also lock/unlock the unit via pin (FC output). A signal on this input corresponds to the activation of the teach element. Type FPKG: (+UB) on pin. Type FNKG: (-UB) on pin. If the FC output wire is activated for less than 0s while the unit is locked, the red LED flashes for about 5s and indicates faulty operation. After about 5s the unit automatically returns to the operating mode. Operation Check whether the unit operates correctly. Indication by LEDs and function check output: LED green LED yellow LEDs yellow + red LED red + FC output unit is ready for operation ON = output is switched flashing = short circuit of the switching output ON = undefined operating range - when the tank is full: the medium is not reliably detected - when the tank is empty: the empty signal has changed since the last adjustment (e.g. caused by deposits of dirt) flashing or Hz signal of the FC output = error during adjustment or locking/unlocking 7