Flow Switch Model Q-16 Stainless Steel Paddle Style

Harwil Catalog version 7.1 05-10-17THE Q-16 STAINLESS STEEL. MAXIMUM RELIABILITY, MINIMUM COST.

The Q-16 Stainless Steel is the newest addition to Harwil’s heavy-duty line of flow switches. The switch is used to signal, start, or stop electronically operated equipment when flow or no-flow conditions occur. The Q-16 Stainless Steel benefits from 40 years of flow switch development experience for every conceivable application.

Harwil’s elastomeric sealing system is superior to the metal bellows that are subject to metal fatigue and corrosion. This seal system has been field-proven for over a decade.

The Q-16 Stainless Steel can be used in pipes 1 inch and larger, with set points as low as 4 GPM (15.2 LPM) to over 500 GPM (1,893 LPM) in larger pipe sizes. The Q-16 uses a 15A SPDT micro switch that can control a ½ horsepower motor.

  • Multiple Quick-Change Paddles
  • EPDM Seal, Superior To Metal Bellows
  • Field Adjustable Set Points
  • Field Adjustable Paddles
  • Direct Replacement For Most Paddle- Type Flow Switches
  • Best Flow Sensitivity Among Paddle-Type Flow Switches
  • Stainless Steel Paddles And Shaft
  • NEMA 1 Enclosure
  • Industry-Leading 3 Year Warranty

Flow Range

4–500 GPM (15–1,893 L/m)

Working Temp

250˚F (121˚C) Maximum

Working Pressure

200 psi (1.379 kPa)

Process Connection

1″ NPT

Electrical (Reed) Switch

SPDT 15A or Dry Circuit

Enclosure

NEMA 1 / IP 10

Installation Instructions

Uses

For use in:

  • Boilers Cooling Towers
  • Chillers Water Treatment
  • Irrigation

Models

Flow Range (Water calibrated at 70˚F / 21˚C) Accuracy ±10%

PIPE SIZE NPT
SWITCHPOINT RANGE (GPM)
MIN. ADJUST. MAX. ADJUST.
ON OFF ON OFF
1″ 4 2 8 7
1½” 7 5 13 11
2″ 12 7 27 26
2½” 18 12 35 32
3″ 27 19 52 49
4″ 63 50 123 120
5″ 125 100 238 232
6″ 190 158 350 338

Specs

HYSTERESIS (Δ FLOW RATE TO ACTIVATE/DEACTIVATE SWITCH)

≈ 10% at upper end of flow range

≈ 30% at lower end of flow range

DIFFERENTIAL PRESSURE DROPS ACROSS UNIT

Under normal operating conditions:

≈ 1″–3″ pipe, less than 1 psi

≈ 4″–48″ pipe, negligible

WORKING LINE PRESSURE 200 psig max.

WORKING TEMPERATURE 250˚F max. continuous.

WETTED MATERIALS

Body: Brass Shaft: 304 Stainless Steel Paddle: 316 stainless steel Seal: EPDM

ELECTRICAL SWITCH CHARACTERISTICS

SPDT 15A, ½ hp @ 125 or 250VAC ½A @ 125VDC ¼A @ 250VDC 10,000,000 Operations Median

Model Q-16 can also be fitted with a SPDT Gold Cross Bar Switch for computer/PLC interface.

Diagram