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The Dwyer A3001 Pressure Switch/Gauge has a range of 0-1.0" w.c.
Photohelic® Switch/Gauges function as versatile, highly repeatable pressure switches combined with a precise pressure gauge employing the time-proven Magnehelic® gauge design. The Photohelic® switch/gage measures and controls positive, negative or differential pressures of air and compatible gases. Standard models are rated to 25 psig (1.7 bar) with options to 35 (2.4) or 80 (5.5 bar) psig. Single pressure 36000S models measure to 6000 psig (413 bar) with a 9000 psig (620 bar) rating. Two phototransistor actuated, DPDT relays are included for low/high limit control. Easy to adjust set point indicators are controlled by knobs located on the gauge face. Individual set point deadband is one pointer width - less than 1% of full scale. Set points can be interlocked to provide variable deadband - ideal for control of fans, dampers, etc. Gauge reading is continuous and unaffected by switch operation, even during loss of electrical power. Choose from full scale pressure ranges from a low 0-.25" (0-6 mm) w.c. up to 30 psi (21 bar); single positive pressure to 6000 psig (413 bar).
Photohelic Sensing - How It Works
In typical applications, these Dwyer switch/gages control between high and low pressure set points. When pressure changes, reaching either set point pressure, the infrared light to the limiting phototransistor is cut off by the helix-driven light shutter. The resulting phototransistor signal is electronically amplified to actuate its DPDT slave relay and switching occurs. Dead band between make and break is 1% of full scale or less - just enough to assure positive, chatter-free operation.
Relay-Transformer Features
A plastic housing protects all electronic components. Solid-state and integrated circuit electronics are on glass-epoxy printed circuit boards and self-extinguishing terminal boards.
| Switch Specifications | |
| Switch Type | Each set point has 2 Form C relays (DPDT) |
| Repeatability | ±1% of FS |
| Electrical Rating | 10 A at 28 VDC 10 A at 120 240 VAC |
| Electrical Connections | Screw terminals. Use 167°F (75°C) copper conductors only |
| Power Requirements | 120 VAC, 50/60 Hz 240 VAC and 24 VAC power optional |
| Mounting Orientation | Diaphragm in vertical position. Consult factory for other position orientations |
| Set Point Adjustment | Adjustable knobs on face |
| Agency Approvals | CE, CSA, UL |
| Gauge Specifications | |
| Service | Air and non-combustible, compatible gases |
| Accuracy | ±2% of FS at 70°F (21.1°C) ±3% on -0 ±4% on -00 models |
| Pressure Limits | -20" Hg to 25 psig (-0.677 to 1.72 bar) MP option; 35 psig (2.41 bar) HP option; 80 psig (5.52 bar) |
| Temperature Limits | 20 to 120°F. (-6.67 to 48.9°C) -20 to 120°F (-28 to 48.9°C) with low temperature option |
| Process Connections | ? female NPT |
| Dimensions | 4" (101.6 mm) dial face 5 x 8¼" (127 x 209.55 mm) |
| Weight | 4 lb (1.81 kg) |
All returns must be authorized. Items returned prior to authorization will not be accepted. For international customers where applicable, customers must ship any returns to us freight and duty prepaid. Return freight charges for internationsl shippments will be the responsibility of the customer.
Defective new equipment may be returned for warrantyrepair/exchange to us within (5) days of the shipment receipt date. After five (5) days, returns will be handled by direct contact and in accordance with the warranty terms of the item's manufacturer. Items that have malfunctioned due to mishandling, electrical overload, etc., will be subject to repair charge.
Non defective new equipment will be authorized for return within five (5) days of the shipment receipt date if the equipment is still in new, re-sellable condition with the original manual(s), accessories, packing material and carton. We reserve the right to reject returnsin which there is no original packaging, missing accessories, damage or visible signs of usage of the item. A restocking fee of up to 25% of purchase price may apply. Special orders and dangerous goods are non-returnable.
(Do not write anytingon the manufacturer's original package or use as a shipping carton. Include all accessories, manuals and warranties.)
Please, include a copy of the packing list or invoice with a reason for the return. Your return authorization number is valid for thirty (30) days.
We can ship to both US and Canada. Note that there are restrictions on some products, and some products cannot be shipped to international destinations.
When you place an order, we will charge a flat rate shipping for your items.
Please also note that the shipping rates for many items we sell are weight-based. The weight of any such item can be found on its detail page. To reflect the policies of the shipping companies we use, all weights will be rounded up to the next full pound.
Not Applicable
| Condition: | NA |
Defective new equipment may be returned for warrantyrepair/exchange to us within (5) days of the shipment receipt date. After five (5) days, returns will be handled by direct contact and in accordance with the warranty terms of the item's manufacturer. Items that have malfunctioned due to mishandling, electrical overload, etc., will be subject to repair charge.
Non defective new equipment will be authorized for return within five (5) days of the shipment receipt date if the equipment is still in new, re-sellable condition with the original manual(s), accessories, packing material and carton. We reserve the right to reject returnsin which there is no original packaging, missing accessories, damage or visible signs of usage of the item. A restocking fee of up to 25% of purchase price may apply. Special orders and dangerous goods are non-returnable.
(Do not write anytingon the manufacturer's original package or use as a shipping carton. Include all accessories, manuals and warranties.)
Please, include a copy of the packing list or invoice with a reason for the return. Your return authorization number is valid for thirty (30) days.
