Overview
The Dwyer Series IS/PX/TX Insite™ Air/Liquid In-Line Flowmeter is a versatile device available in various materials, including PVC, aluminum, brass, and 316 stainless steel. Its optional materials cater to diverse applications. The flowmeter also offers an optional field-adjustable reed switch for high and low alarms.
Flowmeter Diagram
The flowmeter consists of an inlet and an outlet. Fluid enters the "IN" port, pushing a piston against spring pressure. The piston's position, visible through a transparent housing, indicates the flow rate against a printed scale. Key internal components include a piston, spring, piston shaft, and O-rings, all housed within fittings connected to the flowtube.
Dimensional Information
Technical drawings show the flowmeter's dimensions, indicating an overall length of approximately 7 inches (177.80 mm). Connection sizes are available in 1/2", 3/4", 1", and 1-1/2".
Specifications
General
- Service: Compatible gases or liquids.
- Wetted Materials: Flowtube: PVC or Polysulfone; Fittings: Aluminum, brass, 316 SS, PVC, or PVDF; Seal: Viton®.
- Switch Type: Optional 3-wire reed switch.
- Electrical Rating: 0.3 A @ 120 VAC/100 VDC.
- Accuracy: ±5% FS; 3 GPM: ±7% FS.
- Process Connections: 1/2", 3/4", 1", or 1-1/2" selectable.
- Weight: 0.8 to 2.6 lb (0.36 to 1.09 kg).
Temperature and Pressure Limits
| Fluid Temperature | Liquid | Air | ||||
|---|---|---|---|---|---|---|
| °F | °C | psig | bar | psig | bar | |
| PVC | ||||||
| 70 | 21 | 200 | 13.79 | 60 | 4.1 | |
| 100 | 38 | 100 | 6.90 | 50 | 3.41 | |
| 125 | 52 | 75 | 5.17 | 35 | 2.41 | |
| Polysulfone with 316 SS Fittings | ||||||
| 210 | 99 | 200 | 13.8 | 60 | 4.1 | |
| Polysulfone with PVDF Fittings | ||||||
| 120 | 49 | 150 | 10.35 | - | - | |
Accessories
| Model | Description |
|---|---|
| ISS-15-B | Small series switch kit |
| ISS-50-B | Large series switch kit |
| ISS-15-B-T | Small series switch kit Teflon® |
| ISS-50-B-T | Large series switch kit Teflon® |
Installation
Inlet and outlet ends are marked on the flowmeter body with an arrow indicating flow direction. The Insite™ flowmeters can be mounted in any orientation (vertical, horizontal, or angled) without affecting performance.
End fittings connect to the plastic body via O-ring sealed straight threads for a secure, leak-free connection. Avoid over-torquing or using sealant, plumbing tape, or pipe dope. For pipe connections with tapered threads (NPT), use Teflon® tape on the pipe threads and apply standard torques for leak-free connections.
When installing the meter inline, use a wrench only on the end fittings, never on the plastic body.
A disconnect fitting installed upstream of the flowmeter is recommended for easier removal and cleaning. Control valves should be installed downstream.
How it Works
Fluid enters the "IN" port, driving the piston against spring pressure. The piston moves until the flow rate allows it to pass around the piston periphery. The position of the piston's knife edge, visible through the transparent housing, aligns with the printed scale to indicate the flow rate.
Recommended Filtration
System filtration of at least a 74-micron filter or a 200-mesh screen is recommended. Inadequate filtration can lead to meter failure. Proper filtration ensures meter components function correctly and prevents premature wear.
Air Flow Correction Factors
The air flowmeter is calibrated at 90 psi and 70°F. For air at different pressures or temperatures, correction factors must be applied to the 90-PSI air scale readings to obtain correct SCFM values. Multiply the SCFM reading by the applicable factor from the tables below.
Table 1: Pressure Correction Factors
| psig | Factor |
|---|---|
| 10 | 0.49 |
| 20 | 0.58 |
| 30 | 0.65 |
| 40 | 0.72 |
| 50 | 0.79 |
| 60 | 0.84 |
| 70 | 0.90 |
| 80 | 0.95 |
| 90 | 1.00 |
| 100 | 1.05 |
| 110 | 1.09 |
| 120 | 1.13 |
| 125 | 1.16 |
Table 2: Temperature Correction Factors
| Temperature °F | Factor |
|---|---|
| 30 | 1.04 |
| 50 | 1.02 |
| 70 | 1.00 |
| 90 | 0.98 |
| 100 | 0.97 |
| 120 | 0.96 |
| 125 | 0.95 |
Model Chart
The following chart details available models, ranges, process connections, materials, and options.
| Example Series | PX -30GPM | PX-20, 30, 40, and 50 | IS-5, 10, and 15 | IS-20, 30, 40, and 50 | Description | ||||
|---|---|---|---|---|---|---|---|---|---|
| Range | Low | High | Low | High | Low | High | Low | High | |
| 3GPM* | - | 3 GPM water | |||||||
| 5GPM | - | 5 GPM water | |||||||
| 10GPM | - | 10 GPM water | |||||||
| 15GPM | - | 15 GPM water | |||||||
| 20GPM | - | 20 GPM water | |||||||
| 30GPM | - | 30 GPM water | |||||||
| 40GPM | - | 40 GPM water | |||||||
| 50GPM | - | 50 GPM water | |||||||
| 20LPM | - | 20 LPM water | |||||||
| 38LPM | - | 38 LPM water | |||||||
| 55LPM | - | 55 LPM water | |||||||
| 75LPM | - | 75 LPM water | |||||||
| 110LPM | - | 110 LPM water | |||||||
| 150LPM | - | 150 LPM water | |||||||
| 200LPM | - | 200 LPM water | |||||||
| 50SCFM | - | 50 SCFM air | |||||||
| 100SCFM | - | 100 SCFM air | |||||||
| 135SCFM | - | 135 SCFM air | |||||||
| 200SCFM | - | 200 SCFM air | |||||||
| 300SCFM | - | 300 SCFM air | |||||||
| 400SCFM | - | 400 SCFM air | |||||||
| 500SCFM | - | 50 SCFM air | |||||||
| 1400SLPM | - | 1400 SLPM air | |||||||
| 2500SLPM | - | 2500 SLPM air | |||||||
| 3600SLPM | - | 3600 SLPM air | |||||||
| 5500SLPM | - | 5500 SLPM air | |||||||
| 8000SLPM | - | 8000 SLPM air | |||||||
| 11000SLPM | - | 11000 SLPM air | |||||||
| 14000SLPM | - | 14000 SLPM air | |||||||
| Process Connection | 4 | 1/2" (low range only) | |||||||
| 6 | 3/4" | ||||||||
| 8 | 1" | ||||||||
| 12 | 1-1/2" (high range only) | ||||||||
| Connection Material | D | Aluminum | |||||||
| F | Brass | ||||||||
| I | 316 SS | ||||||||
| M4 | PVDF (IS) | ||||||||
| V | PVC (PX and TX only) | ||||||||
| Seal Material | F | Viton® | |||||||
| Options | EP | Electro polished SS shaft and spring (IS only) | |||||||
| IS1 | Installed with one switch kit | ||||||||
| IS2 | Installed with two switch kit | ||||||||
| IS1T | Installed with one switch kit (IS/TX) | ||||||||
| IS2T | Installed with two switch kit (IS/TX) | ||||||||
| ST | SS identification tag | ||||||||
| *Only available with PX series. |
Replacement Parts
The table below lists replacement part numbers for various models and connection sizes.
| Flow Rates and Connection Sizes | PX-3, 5, 10, and 15 | PX-20, 30, 40, and 50 | IS-5, 10, and 15 | IS-20, 30, 40, and 50 | Description | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 3 | 5 | 10 | 15 | 20 | 30 | 40 | 50 | 5 | 10 | 15 | 20 | 30 | 40 | 50 | ||||
| Flow tube assembly with max. flow reading | 1161-AS | 1158-AS | 1159-AS | 1160-AS | - | 1147-AS | 1148-AS | 1149-AS | 1150-AS | 1119-AS | 1116-AS | 1117-AS | 1173-AS | 1174-AS | 1175-AS | 1176-AS | Flow tube assembly with max. flow reading | |
| End fittings for NPT line sizes and materials | 1/2 | 1194-4 | - | 1194-4 | - | 1194-4 | - | 1194-4 | - | 1196-6 | 1194-6 | 1196-6 | 1196-6 | 1196-12 | 1196-12 | Aluminum | ||
| 3/4 | 1194-6 | 1196-6 | 1194-6 | 1196-6 | 1194-6 | 1196-6 | 1194-6 | 1196-6 | 1196-6 | 1196-6 | 1196-12 | 1196-6 | 1196-12 | 1196-12 | Brass | |||
| 1 | 1194-8 | 1196-6 | 1194-8 | 1196-6 | 1194-8 | 1196-6 | 1194-8 | 1196-6 | 1196-6 | 1196-12 | 1196-12 | 1195-6 | 1195-8 | 1195-8 | 316 SS | |||
| 1-1/2 | - | 1196-12 | - | 1196-12 | - | 1196-12 | - | 1196-12 | 1196-12 | 1195-12 | PVC* | |||||||
| 1/2 | 1193-4 | - | 1193-4 | - | 1193-4 | - | 1193-4 | - | 1195-6 | 1193-6 | 1195-6 | 1195-6 | 1195-8 | 1195-8 | Viton® seal | |||
| 3/4 | 1193-6 | 1195-6 | 1193-6 | 1195-6 | 1193-6 | 1195-6 | 1193-6 | 1195-6 | 1195-6 | 1195-8 | 1195-8 | 1195-6 | 1195-8 | 1195-8 | ||||
| 1 | 1193-8 | 1195-8 | 1193-8 | 1195-8 | 1193-8 | 1195-8 | 1193-8 | 1195-8 | 1195-8 | 1195-8 | ||||||||
| 1-1/2 | - | 1195-12 | - | 1195-12 | - | 1195-12 | - | 1195-12 | ||||||||||
| 1/2 | 1188-4 | - | 1188-4 | - | 1188-4 | - | 1188-4 | - | 476-6 | 1188-6 | 476-6 | 476-6 | 476-8 | 476-8 | ||||
| 3/4 | 1188-6 | 476-6 | 1188-6 | 476-6 | 1188-6 | 476-6 | 1188-6 | 476-6 | 476-6 | 476-8 | 476-8 | 476-6 | 476-8 | 476-8 | ||||
| 1 | 1188-8 | 476-8 | 1188-8 | 476-8 | 1188-8 | 476-8 | 1188-8 | 476-8 | 476-8 | 476-8 | ||||||||
| 1-1/2 | - | 476-12 | - | 476-12 | - | 476-12 | - | 476-12 | ||||||||||
| 1/2 | 1191-4 | - | - | - | - | - | - | - | ||||||||||
| 3/4 | 1191-6 | 477-6 | - | - | - | - | - | - | ||||||||||
| 1 | 1191-8 | 477-8 | - | - | - | - | - | - | ||||||||||
| 1-1/2 | - | 477-12 | - | - | - | - | - | - | ||||||||||
| 2 (required) | 1112 | 396 | 1112 | 396 | ||||||||||||||
| *Not available on IS units. | ||||||||||||||||||
Switch Kits
Flowmeters can be equipped with one or two electric switches for flow rate signaling. Switches are field-installable kits.
Each kit includes a magnet that fits around the flowmeter piston and a proximity switch in a housing that clamps to the flowmeter body. The magnet's movement trips the switch, and an adjustment screw sets the actuation point.
Switch Specifications
- Contact Ratings (max.): 8 watts @ 120 VAC/100 VDC.
- Switch Wires: Black (normally open), Blue (normally closed), White (common).
- Switch Specs: 12 VDC @ 0.66 A, 28 VDC @ 0.285 A, 120 VAC @ 0.066 A (at 77°F).
- Operating Band: 25% of full-scale; relay activates within this band.
Switch Kit Part Numbers
- For 3 to 15 GPM: Order No. ISS-15-B.
- For 20 to 50 GPM: Order No. ISS-50-B.
- Note: Additional kits available with Teflon® (ISS-15-B-T, ISS-50-B-T).
Switch Installation
Step 1: Installing the Magnet
Disassemble the flowmeter. Remove the piston from the shaft and place the magnet between the piston and spring. Ensure the piston is correctly oriented and the spring is seated on the magnet and piston. Reassemble the flowmeter.
Step 2: Installing the Foam Gasket
Peel the protective paper from the adhesive side of the foam gasket and press it firmly into place on the switch housing.
Step 3: Installing the Switch Housing(s)
A) Single Switch: Push capscrews through the switch housing tabs and thread them into the half-collars. Use provided washers; nuts can be discarded.
B) Dual Switches: Align tabs on both housings, push capscrews through both collar tabs. Secure with nuts on the threaded ends, using washers. Half-collars and extra magnets may be discarded.
Note: Switch housing orientation is flexible. Install to suit wiring and adjustment needs.
Setting Switch Points
Flowmeter Installed: Adjust flow to position the piston at the desired signal level. Turn the switch adjustment screw clockwise until the switch actuates. Use an ohmmeter to confirm actuation. Repeat for a second switch if applicable.
Flowmeter Not Installed: Simulate flow by pushing a tool (e.g., pencil eraser) through the inlet end to move the piston. Position the piston's knife edge at the desired scale reading. Turn the adjustment screw clockwise until the switch actuates. Repeat for a second switch if applicable.
Note: Leave sufficient lead length on switch wires for full travel.
Insite Switch Parts Description
Diagram Key
- 1. HOUSING
- 2. GASKET
- 3. MAGNET
- 4. HALF-COLLARS (2)
- 5. CAPSCREWS (4)
- 6. CAPSCREW NUTS (2)
- 7. SWITCH
- 8. SWITCH CARRIER
- 9. ADJUSTMENT SCREW
- 10. O-RING (2)
- 11. RETAINER CLIP
- 12. LOCKWASHERS (4)
- 13. 1/2" NPTF CONDUIT CONNECTION
Maintenance and Repair
Periodic cleaning of the tube and internal parts is the primary servicing requirement.
To remove the flowmeter, use wrenches on the end fittings only; avoid applying force to the plastic body.
After removal, detach the outlet end fitting. Use a hook to extract the shaft, piston, and spring. Inspect all parts for damage. The tube interior can be cleaned with a soft dry cloth. If residue persists, use water and mild, non-abrasive soap. Do not use solvents.
Replace any worn or damaged parts. During reassembly, ensure the piston is correctly oriented. Inspect O-rings for damage and replace if necessary. Wet O-rings with water before assembly for better sealing.
Warranty and Return
Refer to "Terms and Conditions of Sale" in the Dwyer catalog or website. Contact customer service for a Return Materials Authorization (RMA) number before shipping for repair. Include a brief problem description and application notes.
