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Series 3000MR/3000MRS Photohelic® Switch/Gage

Series AT-A3000 ATEX/IECEx Approved Photohelic® Pressure Switch/Gage

Series A3000 Photohelic® Pressure Switch/Gage

3-in-1 Indicating Gage, Lo-limit and Hi-limit Control

The Series A3000 Photohelic® Switch/Gages function as versatile, highly repeatable pressure switches combined with a precise pressure gage employing the time-proven Magnehelic® gage 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. 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 gage 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. Gage 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 in (0-6 mm) w.c. up to 30 psi (21 bar).

NIST CALIBRATION available in Product Configurator.

Please see Series AT-A3000 for ATEX approved.

DID YOU KNOW that you can add YOUR logo to our Photohelic® Switch/Gage, call customer service for details.

Product Applications

Air Conditioning Systems
Clean Rooms
Fume Exhaust Systems

Ordering

Grouped product items
Model	Description	Availability*	Price
A3000-0	Pressure switch/gage, range 0-.50" w.c.	1-3 days*	$668.70
A3000-00	Pressure switch/gage, range 0-.25" w.c.	1-3 days*	$706.15
A3000-00AV	Pressure switch/gage, range 0-.25" w.c./300-2000 FPM. Note: Pitot tube required.	1-2 Weeks*	$706.15
A3000-00N	Pressure switch/gage, range .05 to .20" w.c.	1-2 Weeks*	$706.15
A3000-0AV	Pressure switch/gage, range 0-.50" w.c./500-2800 FPM. Note: Pitot tube required.	1-2 Weeks*	$668.70
A3000-1.5KPA	Pressure switch/gage, range 0-1.5 kPa.	1-2 Weeks*	$668.70
A3000-100CM	Pressure switch/gage, range 0-100 cm w.c.	1-2 Weeks*	$668.70
A3000-100MM	Pressure switch/gage, range 0-100 mm w.c.	1-3 days*	$668.70
A3000-10KPA	Pressure switch/gage, range 0-10 kPa.	1-2 Weeks*	$668.70
A3000-10MM	Pressure switch/gage, range 0-10 mm w.c.	1-2 Weeks*	$668.70
A3000-125PA	Pressure switch/gage, range 0-125 Pa.	1-2 Weeks*	$668.70
A3000-150CM	Pressure switch/gage, range 0-150 cm w.c.	1-2 Weeks*	$668.70
A3000-15CM	Pressure switch/gage, range 0-15 cm w.c.	1-2 Weeks*	$668.70
A3000-15KPA	Pressure switch/gage, range 0-15 kPa.	1-2 Weeks*	$668.70
A3000-1KPA	Pressure switch/gage, range 0-1 kPa.	1-2 Weeks*	$668.70
A3000-200CM	Pressure switch/gage, range 0-200 cm w.c.	1-2 Weeks*	$668.70
A3000-20CM	Pressure switch/gage, range 0-20 cm w.c.	1-2 Weeks*	$668.70
A3000-20KPA	Pressure switch/gage, range 0-20 kPa.	1-2 Weeks*	$668.70
A3000-250CM	Pressure switch/gage, range 0-250 cm w.c.	1-2 Weeks*	$668.70
A3000-250PA	Pressure switch/gage, range 0-250 Pa.	1-2 Weeks*	$668.70
A3000-10CM	Pressure switch/gage, range 0-10 cm w.c.	1-2 Weeks*	$668.70
A3000-25CM	Pressure switch/gage, range 0-25 cm w.c.	1-2 Weeks*	$668.70
A3000-150MM	Pressure switch/gage, range 0-150 mm w.c.	1-2 Weeks*	$668.70
A3000-25KPA	Pressure switch/gage, range 0-25 kPa.	1-2 Weeks*	$668.70
A3000-250MM	Pressure switch/gage, range 0-250 mm w.c.	1-2 Weeks*	$668.70
A3000-25MM	Pressure switch/gage, range 0-25 mm w.c.	1-2 Weeks*	$668.70
A3000-300CM	Pressure switch/gage, range 0-300 cm w.c.	1-2 Weeks*	$668.70
A3000-30CM	Pressure switch/gage, range 0-30 cm w.c.	1-2 Weeks*	$668.70
A3000-40CM	Pressure switch/gage, range 0-40 cm w.c.	1-2 Weeks*	$668.70
A3000-30KPA	Pressure switch/gage, range 0-30 kPa.	1-2 Weeks*	$668.70
A3000-3KPA	Pressure switch/gage, range 0-3 kPa.	1-2 Weeks*	$668.70
A3300-20CM	Pressure switch/gage, range 10-0-10 cm w.c.	1-2 Weeks*	$687.45
A3000-4KPA	Pressure switch/gage, range 0-4 kPa.	1-2 Weeks*	$668.70
A3000-1CM	Pressure switch/gage, range 0-1 cm w.c.	1-2 Weeks*	$668.70
A3000-500PA	Pressure switch/gage, range 0-500 Pa.	1-2 Weeks*	$668.70
A3000-2CM	Pressure switch/gage, range 0-2 cm w.c.	1-2 Weeks*	$668.70
A3000-50CM	Pressure switch/gage, range 0-50 cm w.c.	1-2 Weeks*	$668.70
A3000-5CM	Pressure switch/gage, range 0-5 cm w.c.	1-2 Weeks*	$668.70
A3000-50MM	Pressure switch/gage, range 0-50 mm w.c.	1-2 Weeks*	$668.70
A3000-8CM	Pressure switch/gage, range 0-8 cm w.c.	1-2 Weeks*	$668.70
A3000-5KPA	Pressure switch/gage, range 0-5 kPa.	1-2 Weeks*	$668.70
A3300-4CM	Pressure switch/gage, range 2-0-2 cm w.c.	1-2 Weeks*	$687.45
A3300-10CM	Pressure switch/gage, range 5-0-5 cm w.c.	1-2 Weeks*	$687.45
A3000-60PA	Pressure switch/gage, range 0-60 Pa.	1-2 Weeks*	$706.15
A3300-30CM	Pressure switch/gage, range 15-0-15 cm w.c.	1-2 Weeks*	$687.45
A3000-6MM	Pressure switch/gage, range 0-6 mm w.c.	1-2 Weeks*	$706.15
A3000-750PA	Pressure switch/gage, range 0-750 Pa.	1-2 Weeks*	$668.70
A3000-20MM	Pressure switch/gage, range 0-20 mm w.c.	1-2 Weeks*	$668.70
A3000-80CM	Pressure switch/gage, range 0-80 cm w.c.	1-2 Weeks*	$668.70
A3000-80MM	Pressure switch/gage, range 0-80 mm w.c	1-2 Weeks*	$668.70
A3000-8KPA	Pressure switch/gage, range 0-8 kPa.	1-2 Weeks*	$668.70
A3001	Pressure switch/gage, range 0-1.0" w.c.	1-3 days*	$668.70
A3001AV	Pressure switch/gage, range 0-1.0" w.c.500-4000 FPM. Note: Pitot tube required.	1-2 Weeks*	$668.70
A3002	Pressure switch/gage, range 0-2.0" w.c.	1-3 days*	$668.70
A3002AV	Pressure switch/gage, range 0-2.0" w.c./1000-5600 FPM. Note: Pitot tube required.	1-2 Weeks*	$668.70
A3003	Pressure switch/gage, range 0-3.0" w.c.	1-3 days*	$668.70
A3004	Pressure switch/gage, range 0-4.0" w.c.	1-3 days*	$668.70
A3005	Pressure switch/gage, range 0-5.0" w.c.	1-3 days*	$668.70
A3006	Pressure switch/gage, range 0-6.0" w.c.	1-3 days*	$668.70
A3008	Pressure switch/gage, range 0-8.0" w.c.	1-3 days*	$668.70
A3010	Pressure switch/gage, range 0-10" w.c.	1-3 days*	$668.70
A3010AV	Pressure switch/gage, range 0-10" w.c./2000-12500 FPM. Note: Pitot tube required.	1-2 Weeks*	$668.70
A3015	Pressure switch/gage, range 0-15" w.c.	1-3 days*	$668.70
A3020	Pressure switch/gage, range 0-20" w.c.	1-3 days*	$668.70
A3025	Pressure switch/gage, range 0-25" w.c.	1-3 days*	$668.70
A3030	Pressure switch/gage, range 0-30" w.c.	1-3 days*	$668.70
A3040	Pressure switch/gage, range 0-40" w.c.	1-3 days*	$668.70
A3050	Pressure switch/gage, range 0-50" w.c.	1-3 days*	$668.70
A3060	Pressure switch/gage, range 0-60" w.c.	1-2 Weeks*	$668.70
A3080	Pressure switch/gage, range 0-80" w.c.	1-2 Weeks*	$668.70
A3100	Pressure switch/gage, range 0-100" w.c.	1-3 days*	$668.70
A3150	Pressure switch/gage, range 0-150" w.c.	1-2 Weeks*	$668.70
A3201	Pressure switch/gage, range 0-1 psi.	1-2 Weeks*	$668.70
A3202	Pressure switch/gage, range 0-2 psi.	1-2 Weeks*	$668.70
A3203	Pressure switch/gage, range 0-3 psi.	1-2 Weeks*	$668.70
A3204	Pressure switch/gage, range 0-4 psi.	1-2 Weeks*	$668.70
A3205	Pressure switch/gage, range 0-5 psi.	1-2 Weeks*	$668.70
A3210	Pressure switch/gage, range 0-10 psi, medium pressure option standard.	1-2 Weeks*	$773.75
A3215	Pressure switch/gage, range 0-15 psi, medium pressure option standard.	1-3 days*	$773.75
A3220	Pressure switch/gage, range 0-20 psi, medium pressure option standard.	1-2 Weeks*	$773.75
A3230	Pressure switch/gage, range 0-30 psi, high pressure option standard.	1-2 Weeks*	$963.00
A3300-0	Pressure switch/gage, range .25-0-.25" w.c.	1-3 days*	$706.15
A3300-1KPA	Pressure switch/gage, range .5-0-.5 kPa.	1-2 Weeks*	$687.45
A3300-20MM	Pressure switch/gage, range 10-0-10 mm w.c.	1-2 Weeks*	$687.45
A3300-250PA	Pressure switch/gage, range 125-0-125 Pa.	1-2 Weeks*	$687.45
A3300-30MM	Pressure switch/gage, range 15-0-15 mm w.c.	1-2 Weeks*	$687.45
A3300-3KPA	Pressure switch/gage, range 1.5-0-1.5 kPa.	1-2 Weeks*	$687.45
A3300-500PA	Pressure switch/gage, range 250-0-250 Pa.	1-2 Weeks*	$687.45
A3301	Pressure switch/gage, range .5-0-.5" w.c.	1-3 days*	$687.45
A3302	Pressure switch/gage, range 1-0-1" w.c.	1-3 days*	$687.45
A3304	Pressure switch/gage, range 2-0-2" w.c.	1-2 Weeks*	$687.45
A3310	Pressure switch/gage, range 5-0-5" w.c.	1-3 days*	$687.45
A3320	Pressure switch/gage, range 10-0-10" w.c.	1-2 Weeks*	$687.45
A3330	Pressure switch/gage, range 15-0-15" w.c.	1-2 Weeks*	$687.45

Specifications

: GAGE SPECIFICATIONS
Service:: Air and non-combustible, compatible gases.
Wetted Materials:: Consult Factory.
Accuracy:: ±2% of FS at 70°F (21.1°C). ±3% on -0 and ±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:: 1/8" female NPT.
Size:: 4" (101.6 mm) dial face, 5" (127 mm) O.D. x 8-1/4" (209.55 mm).
Weight:: 4 lb (1.81 kg).
: SWITCH SPECIFICATIONS
Switch Type:: Each setpoint has 2 Form C relays (DPDT).
Repeatability:: ±1% of FS.
Electrical Rating:: 10 A @ 28 VDC, 10 A @ 120, 240 VAC.
Electrical Connections:: Screw terminals. Use 167°F (75°C) copper conductors only.
Power Requirements:: 120 VAC, 50/60 Hz; 240 VAC & 24 VAC power optional.
Mounting Orientation:: Diaphragm in vertical position. Consult factory for other position orientations.
Set Point Adjustment:: Adjustable knobs on face.
Compliance:: CE, CSA, UL.

Features

Bezel and front cover (with set point knobs and zero adjustment screw) removed to expose Photohelic® switch/gage set point mechanism. Cover is clear polycarbonate plastic.
Gage pointer and light shutter are mounted on helix and balancing counterweight. Shutter passes through slot in optical limit switch to expose phototransistors to integral infrared light source or mask them depending on applied pressure.
Light shield effectively protects phototransistors from strong outside light sources yet allows free pointer movement. It also gives interior a clean "finished" look.
Optical limit switches are used for reliability and long service life. Attached directly to set pointers, they are individually aligned to assure precise switching accuracy.
Semi-Flexible drive shaft connects to set point knobs.
Zero adjustment screw connects to screw in cover to adjust zero pressure reading.
Plastic enclosure protects electronic components and electrical connections.
Polycarbonate connection or terminal board is self-extinguishing.
Glass epoxy printed circuit boards for durability and permanence.
Load relays are DPDT with latching feature for maximum application versatility.
Electronics are designed to operate on 50/60 Hz, 120 volt current with 10% over or under voltage. Special units for other voltages are available.
Switch set pointers show switch settings at all times.
Spring loaded friction clutch prevents operator damage of set point mechanism.
3-in-1 instrument allows the reduction of several instruments with one product, saving inventory, installation time and money.
Patented design and 1% full scale dead band provides quick response to pressure changes means no delay in switching and chatter-free operation.
A wide range of models that can meet pressure measurement specifications from low to very high.

Options

-SR Single contact, right set point, for actuation on increasing or decreasing pressure.
-OLS OEM Model, less relay and transformer components and housing but including infared diodes and phototransistor(s), light shutter and set pointer(s). For single or double contact.
-RMR Remote-Mounted Relay, relay pack may be mounted remotely from gage. Standard length is 5 ft. For other lengths, specify cable length required.
-TAMP Tamper-proof knobs, low temperature option, special scales, voltages and other features and modifications are available.
Special Housings available include Weatherproof (NEMA 4) and Explosion-proof (NEMA 7 & 9; NEC Cl I, Gr C&D; Cl II, Gr E, F&G; Cl III). Contact Customer Service for detailed dimension drawings.
Scale No. 3401 Square Root Specify Range.
Scale No. 3402 Blank Scale Specify Range.
High & Low Latching Circuits. Dwyer Photohelic® switch/gages can be wired for high-latching, low-latching or combination high-low latching circuits. That is, the equipment will hold in these respective positions once activated and until manually reset. This can be particularly useful for alarm and signal applications where control is accomplished by another Photohelic® switch/gage or other means. Complete wiring and operational instructions are included. Where manual reset is required a dry circuit push button such as Dwyer Part A-601 should be used.

Support Library

Product Literature

Manuals

Catalog Pages

Series A3000 Catalog Page

Approvals

Drawings

Videos

Model Chart

EXAMPLE	A3000-00N	24VAC	Series A3000-00N-24VAC Photohelic® Pressure Switch/Gage, range .05-0-0.2" w.c., with 24VAC relay pack.
RANGE	A3000-00N A3000-00 A3000-0 A3001 A3002 A3003 A3004 A3005 A3006 A3008 A3010 A3015 A3020 A3025 A3030 A3040 A3050 A3060 A3080 A3100 A3150 A3300-0 A3301 A3302 A3304 A3310 A3320 A3330 A3000-00AV A3000-0AV A3001AV A3002AV A3010AV A3201 A3202 A3203 A3204 A3205 A3210 A3215 A3220 A3230 A3000-5HG A3000-10HG A3000-15HG A3000-20HG A3000-25HG A3000-30HG A3000-40HG A3000-50HG A3000-60HG A3000-6MM A3000-10MM A3000-20MM A3000-25MM A3000-50MM A3000-80MM A3000-100MM A3000-150MM A3000-200MM A3000-250MM A3000-300MM A3000-400MM A3000-500MM A3000-5000MM A3300-20MM A3300-30MM A3000-200MMHG A3000-1CM A3000-2CM A3000-5CM A3000-8CM A3000-10CM A3000-15CM A3000-20CM A3000-25CM A3000-30CM A3000-40CM A3000-50CM A3000-80CM A3000-100CM A3000-150CM A3000-200CM A3000-250CM A3000-300CM A3300-4CM A3300-10CM A3300-20CM A3300-30CM A3000-60PA A3000-125PA A3000-250PA A3000-500PA A3000-750PA A3300-250PA A3300-500PA A3000-.5KPA A3000-1KPA A3000-1.5KPA A3000-2KPA A3000-3KPA A3000-4KPA A3000-5KPA A3000-8KPA A3000-10KPA A3000-15KPA A3000-20KPA A3000-25KPA A3000-30KPA A3300-1KPA A3300-2KPA A3300-3KPA A3000-5MBAR A3000-25MBAR		.05-0-.2" w.c. 0-0.25" w.c. 0-0.5" w.c. 0-1" w.c. 0-2" w.c. 0-3" w.c. 0-4" w.c. 0-5" w.c. 0-6" w.c. 0-8" w.c. 0-10" w.c. 0-15" w.c. 0-20" w.c. 0-25" w.c. 0-30" w.c. 0-40" w.c. 0-50" w.c. 0-60" w.c. 0-80" w.c. 0-100" w.c. 0-150" w.c. .25-0.25" w.c. .5-0-.5" w.c. 1-0-1" w.c. 2-0-2" w.c. 5-0-5" w.c. 10-0-10" w.c. 15-0-15" w.c. 0-.25" w.c. & 300-2000 FPM AV 0-.5" w.c. & 500-2800 FPM AV 0-1" w.c. & 500-4000 FPM AV 0-2" w.c. & 1000-5600 FPM AV 0-10" w.c. & 2000-12500 FPM AV 0-1 psid 0-2 psid 0-3 psid 0-4 psid 0-5 psid 0-10 psid 0-15 psid 0-20 psid 0-30 psid 0-5" Hg 0-10" Hg 0-15" Hg 0-20" Hg 0-25" Hg 0-30" Hg 0-40" Hg 0-50" Hg 0-60" Hg 0-6 mm w.c. 0-10 mm w.c. 0-20 mm w.c. 0-25 mm w.c. 0-50 mm w.c. 0-80 mm w.c. 0-100 mm w.c. 0-150 mm w.c. 0-200 mm w.c. 0-250 mm w.c. 0-300 mm w.c. 0-400 mm w.c. 0-500 mm w.c. 0-5000 mm w.c. 10-0-10 mm w.c. 15-0-15 mm w.c. 0-200 mm Hg 0-1 cm w.c. 0-2 cm w.c. 0-5 cm w.c. 0-8 cm w.c. 0-10 cm w.c. 0-15 cm w.c. 0-20 cm w.c. 0-25 cm w.c. 0-30 cm w.c. 0-40 cm w.c. 0-50 cm w.c. 0-80 cm w.c. 0-100 cm w.c. 0-150 cm w.c. 0-200 cm w.c. 0-250 cm w.c. 0-300 cm w.c. 2-0-2" cm w.c. 5-0-5 cm w.c. 10-0-10 cm w.c. 15-0-15 cm w.c. 0-60 Pa 0-125 Pa 0-250 Pa 0-500 Pa 0-750 Pa 125-0-125 Pa 250-0-250 Pa 0-0.5 kPa 0-1 kPa 0-1.5 kPa 0-2 kPa 0-3 kPa 0-4 kPa 0-5 kPa 0-8 kPa 0-10 kPa 0-15 kPa 0-20 kPa 0-25 kPa 0-30 kPa 0.5-0-0.5 kPa 1-0-1 kPa 1.5-0-1.5 kPa 0-5 mbar 0-25 mbar
OPTIONS		24VAC 240VAC AT COO DEED EDED EDDE ED EXPL G HC HL HP LH LL OLS LT M MP NIST R RMR RMR1 RMR2 RMR3 RMR10 RMR15 RMR20 RMR25 RMR30 RMR40 RMR50 RMR60 RMR70 RMR80 RMR90 RMR100 SRH SRL ST TA TAMP WP Y	24 VAC Relay Pack 220/240 VAC Relay Pack Aluminum Tag Certificate of Origin Energizing (set point low: de-energizing/energizing; set point high: energizing/de-energizing) Energizing (set point low: energizing/de-energizing; set point high: energizing/de-energizing) Energizing (set point low: energizing/de-energizing; set point high: de-energizing/energizing) Energizing (set point: energizing/de-energizing) Explosion-proof Housing with Breather & Drain Green Scale Overlay Horizontal Calibration (90° face up) Latching Option (high/low) High Pressure Latching Option (low/high) Latching Option (low/low) Less Relay Low Temperature Mirror Scale Overlay Medium Pressure NIST Certificate of Calibration Red Scale Overlay Remote Mounted Relay Std. 5 Ft. Remote Mounted Relay 1 Ft. Remote Mounted Relay 2 Ft. Remote Mounted Relay 3 Ft. Remote Mounted Relay 10 Ft. Remote Mounted Relay 15 Ft. Remote Mounted Relay 20 Ft. Remote Mounted Relay 25 Ft. Remote Mounted Relay 30 Ft. Remote Mounted Relay 40 Ft. Remote Mounted Relay 50 Ft. Remote Mounted Relay 60 Ft. Remote Mounted Relay 70 Ft. Remote Mounted Relay 80 Ft. Remote Mounted Relay 90 Ft. Remote Mounted Relay 100 Ft. Single Right Hi Latching Single Right Lo Latching Stainless Steel Tag Tilt Angle from Vertical in Degrees (-90 to 90) Tamperproof Knobs Weatherproof Housing Yellow Scale Overlay

FAQ

Questions

Question

Are air velocity scales available?

Answer

Yes, the information we require to supply the proper range is the velocity (fpm or m/s) or velocity pressure (inches of water or kpa) and density of air (lb/ft3 or g/cm3).

Related

Series A3000

Series 2000

Question

What is the NEMA rating of a Photohelic®?

Answer

Our standard is considered to be NEMA 1 rated for general purpose. We do have weatherproof (NEMA 4X) and explosion-proof (NEMA 7 & 9) enclosures available.

Related

Series 3000MR/3000MRS

Series A3000

Series 43000

Question

What is an RMR Photohelic®?

Answer

The RMR option is for a remote mounted relay, where the relay pack is seperate from the gage. The unit comes with a standard interconnecting cable that is 3 feet long.

Related

Series A3000

Question

What restrictions, if any, are imposed for the Magnehelic® and Photohelic® gages in vacuum service?

Answer

In applications involving higher vacuums than 20" Hg, leakage due to gage housing porosity becomes the limiting factor.

Related

Series MP

Series 2000-SP

Series 2000

Series 3000MR/3000MRS

Series 605

Series DCTE

Series A3000

Series 43000

Apps

Air Velocity and Flow Calculator

Reviews

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Accessories

Model	Description	Availability*	Price
A-298	Flat aluminum bracket for flush mounting (for Series A3000 Photohelic®, Series 4000 Capsuhelic®, Series 605, and Series 3000MR)	1-3 days*	$37.65
A-601	Manual reset switch	1-3 days*	$67.10
410518-00	Adjustment tool for tamper-proof option	1-2 Weeks*	$3.95