Serie QInterruttore a galleggiante per impieghi gravosi

Il fratello maggiore e più robusto della Serie K — galleggiante in polipropilene per impieghi gravosi, interamente sovrastampato attorno a un cavo a tre conduttori di alta qualità. Microinterruttore S.P.D.T. per impieghi gravosi da 21 A a 250 V AC, in grado di comandare direttamente piccoli motori di pompe. Sigillato, a prova di manomissione, senza parti metalliche a contatto con il liquido e altamente resistente agli agenti chimici.

Serie Q

Caratteristiche

  • Microinterruttore Omron per impieghi gravosi da 21 A (250 VAC resistivi)
  • Galleggiante in polipropilene extra resistente
  • Interruttore S.P.D.T. a tre fili
  • Nessun componente con mercurio o piombo
  • Cavo in gomma CPE di alta qualità
  • Nessuna parte metallica a contatto con il liquido
  • Struttura sigillata a prova di manomissione
  • Elevata resistenza chimica
  • Ampia gamma di sezioni del cavo disponibili

L’interruttore a galleggiante della Serie Q è costituito da un galleggiante in polipropilene per impieghi gravosi interamente sovrastampato attorno a un cavo a tre conduttori di alta qualità. Il galleggiante contiene un interruttore unipolare a due vie (S.P.D.T.) che scatta quando il galleggiante si inclina — consente un controllo regolabile del livello del liquido in serbatoi, fosse e bacini, e un attento ancoraggio del cavo imposta l’azione di accensione o spegnimento nella posizione desiderata. L’interruttore per impieghi gravosi può comandare direttamente piccoli motori di pompe (carico minimo 160 mA a 5 V DC). Il galleggiante è in polipropilene di qualità elevata, interamente sovrastampato e privo di pressacavo esterno, e i collegamenti dell’interruttore sono incapsulati in polipropilene per impedire all’acqua di risalire lungo i conduttori. Il galleggiante sigillato, senza giunzioni e senza pressacavo è completamente a prova di manomissione ed estremamente robusto. Il cavo per impieghi gravosi, prodotto appositamente, ha isolamento in EPR e guaina in CPE ed è progettato per l’immersione permanente in acqua. L’interruttore e il cavo resistono anche a olio, grasso, sostanze grasse, acque reflue e a diversi agenti chimici.

Selezioni il modello

Come commuta la Serie Q

POMPAPUNTO DI ANCORAGGIOKELCOQ SERIESSCARICOALTOBASSO≈ 300 mm
Interruttore S.P.D.T. a 3 fili
Contatto
COM → NC
Pompa
Acceso

Qui la pompa riempie il serbatoio, quindi è collegata al comune (blu) e al normalmente chiuso (nero); per svuotare un serbatoio, utilizzi il comune e il normalmente aperto (marrone). Differenziale di commutazione massimo circa 300 mm in acqua senza peso sul cavo (170 mm con un peso sul cavo a 100 mm dal galleggiante). Cablaggio e differenziale tratti dalla scheda tecnica della Serie Q.

Ordini — modelli disponibili

Codice modelloDescrizione
Q4MQ Series float switch — 4 m of CPE cable
Q6MQ Series float switch — 6 m of CPE cable
Q10MQ Series float switch — 10 m of CPE cable (most common)
Q15MQ Series float switch — 15 m of CPE cable
Q20MQ Series float switch — 20 m of CPE cable
Q30MQ Series float switch — 30 m of CPE cable
Q50MQ Series float switch — 50 m of CPE cable

Limiti di funzionamento

Maximum submergence30 m / 300 kPa static pressure
Maximum liquid temperature60 °C
Minimum liquid temperature-20 °C
Liquid specific gravity> 0.82
Liquid pH range1 to 14
Smallest well diameter600 mm
Liquid level change for switch operation300 mm (approximately)
Smallest opening through which the switch will fit108 mm
Minimum distance from float to closest tether/weight100 mm
Liquid level change with cable weight mounted 100 mm from float170 mm (300 mm maximum with no cable weight)
Suitability — sodium hypochloriteFully compatible
Suitability — sea waterFully compatible
Suitability — potable waterNot approved
Maximum suspended lengthApprox. 40 m (cable only)
Minimum cable bend radius6 × overall diameter (54 mm)

Dati elettrici

Switch typeSingle-pole double-throw, silver-alloy contacts, 1 mm gap
Rated voltage250 V AC; 125 and 250 V DC (low voltage recommended)
Resistive AC current rating21 A at 250 V
Motor load AC current rating4 A at 250 V AC
Mechanical life expectancy50 000 000 operations minimum
Electrical life expectancy100 000 operations minimum
Resistive DC current rating0.6 A at 125 V DC, 0.3 A at 250 V DC
UL rating21 A, ½ HP at 125/250 V AC
Minimum applicable load160 mA at 5 V DC
Low-current inputsThe 160 mA at 5 V DC minimum is the microswitch manufacturer's rating for guaranteed contact at very low currents. Q Series switches are also used on PLC, BMS and 24 V DC control inputs. For a dedicated low-current signal input, the KP-10 reed probe and the L-L side-entry switch (gold contacts) are designed for that duty.
Maximum operating frequency, electrical60 operations per minute
Contact resistance15 mΩ max (initial)
Insulation resistance100 MΩ min (at 500 V DC)
Dielectric strength, same polarity1000 V AC, 50/60 Hz for 1 minute
Dielectric strength, live parts to ground2000 V AC, 50/60 Hz for 1 minute
Microswitch approvalsUL1054, File No E41515; CSA C22.2 No. 55, File No LR21642
Product current rating10 A max (cable limited)
Cable typeS07RN-F 3 × 1.0 mm² (heavy duty rubber, CE)
Cable outer sheathingCPE (chlorinated polyethylene), black
Cable core insulationEPR
Cable cores3 × 1.0 mm², 32/0.2 mm plain copper
Cable diameter9.0 ± 0.2 mm
Core coloursBlue (common), black (NC), brown (NO)
Cable voltage rating Uo/U450/750 V
Cable AC test voltage2000 V / 2500 V
Conductor resistance20.0 Ω/km max per core at 20 °C
Conductor operating temperature-30 °C to +60 °C (85 °C max)
Standard of constructionCENELEC HD 22.4 S4 & VDE 0282-4/2005
Cable lengths available4, 6, 10, 15, 20, 30, 50 metres

Dimensioni

Dimensioni di Serie Q
Cable-suspended pendant float — fully overmoulded polypropylene float with three-core CPE cable. Overall dimensions: 108 mm wide, 56 mm high and 180 mm long, on 9 mm diameter cable. Available in 4, 6, 10, 15, 20, 30 or 50 m lengths.

Typical Applications

High and low level control; loss-of-prime protection for pumps; automatic control of sump pumps; control of tank filling and draining valves; level control in effluent and separation pits; level control in bulk-liquid tanks; control of level-warning equipment; alarms, pump control (direct or through a contactor or relay), and PLC / BMS inputs.

Suitable Liquids

The Q Series is suitable for use in clean water as well as in waste and effluents. It is a fully overmoulded polypropylene float with an EPR/CPE cable and has no metal parts in contact with the process liquid, so it can be used in water, seawater, acids, alkalis and a great variety of chemical solutions, including oil, oily waste, fats and effluent of many types. Not approved for use in potable water. No mercury is used in this switch.

QCW Cable Weight (separate accessory)

The QCW is a split heavy-grade polypropylene cable weight with a 316 stainless steel screw and nut. It clamps to the Q-series cable to act as the tether/pivot for the float’s tilt action when the float is suspended down a deep sump or pit. To fit it, unscrew the halves, place the cable in the channel, reassemble, position the weight on the cable where desired and tighten the halves, at least 100 mm from the float. With the cable weight mounted 100 mm from the float, the ON / OFF level change is reduced to 170 mm (300 mm maximum with no cable weight).

Installation

Avoid areas with excessive turbulence and anywhere the switch will rub or foul against any object — abrasion between the cable and adjacent surfaces greatly reduces the life of the switch. Where several float switches are installed, keep the cables from tangling or abrading against each other. Where possible, tether the switch cable to a suitable standpipe, and do not tether the cable closer than 100 mm from the end of the cable boot. Keep the exposed rubber cable out of direct sunlight: at the top of a tank, terminate the float switch in a suitable junction box rather than draping the cable over the tank rim or across exposed ground. Multiple float switches can be tidily installed using a length of PVC pipe as a central cable conduit, or a float switch can be strapped to a pump discharge pipe with cable ties.

Wiring

Connection is via three core 1.0 mm² S07RN-F (EPR/CPE) cable. The cable cannot be replaced; if it is damaged, replace the complete switch. The blue wire is common. With the switch hanging vertically down, black to blue is closed and brown to blue is open; if the switch is inverted (cable hanging vertically below the switch), blue to black is open circuit and blue to brown is closed. Most applications only need the common (blue) wire and either the black or brown wire — in all two-wire applications, insulate the end of the unused third wire, as it will become live when the switch changes state. Terminate the float switch in a junction box as close as practical and well above the liquid level, and avoid running the cable any appreciable distance through conduit.

Using Two Float Switches

The difference in height between the on and the off point is 300 mm (approximately), in water. For applications where the level change is greater than 300 mm, use two switches, one to actuate at high level and one at low level. Where two float switches are used in a control circuit, for example for filling or pumping out a deep tank, a relay must be used in the control circuit: a double pole relay latches the circuit ON, and the latch is broken by either the high level or the low level float switch changing state. A suitable relay may directly control the pump motor, but it is preferable that the control circuit is operated at low voltage with the relay contacts used to control a suitable mains voltage contactor, which in turn controls the pump motor.

Hazardous Areas

The Q Series is not certified for use in hazardous areas and must not be installed in any area classified as hazardous under AS/NZS 60079.10 (Zone 0, 1, 2, 20, 21 or 22).

Safety Note

The Q Series is a mains voltage device rated 250 V AC, but local electrical codes may require the switch to be isolated to a low voltage supply regardless of its high voltage rating. In the interest of safety, lower voltages, such as 24 or 48 volts, should be used wherever possible. Check with your local electrical authority before connecting to a mains voltage supply. If the switch is used in a 240 volt control circuit, it must always be isolated via a residual current device (RCD). All electrical work must be carried out by a qualified, licensed electrician and conform to AS/NZS 3000 (or equivalent) standards and local wiring rules. Ensure the float is installed where it will not be subjected to entanglement, severe agitation or abrasion against tank walls or moving equipment.

Manutenibilità

Unità sigillata — non riparabile internamente dall’utente. Il cavo non può essere sostituito; se è danneggiato, sostituire l’intero interruttore. I contrappesi per cavo QCW sono disponibili presso Kelco Engineering o il Suo distributore.

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