Select Product
Type

Design

Scale Range

ISO Class

Terra Part # Price Ships in
Digihelic® Pressure Gauge Analog 0-4.0" WC ISO 8 2625-17 11737 $891 15-21 Days 2
Digihelic® Pressure Gauge Digital 0-1.0" WC ISO 8 2625-26 41589 $1,076 40-46 Days 3
Digihelic® Pressure Gauge Digital 0-5.0" WC ISO 8 2625-27 41590 $847 40-46 Days 4
Digihelic® Pressure Gauge Digital 1.0-0-1.0" WC ISO 8 2625-28 41591 $955 40-46 Days 5
Magnehelic® Pressure Gauge Analog 0-0.5" WC ISO 8 2625-08 11728 $170 1-3 Days 6
Quick Ship+ In stock
Magnehelic® Pressure Gauge Analog 0-1.0" WC ISO 8 2625-09 11729 $148 15-21 Days 7
Magnehelic® Pressure Gauge Analog 0-2.0" WC ISO 8 2625-10 11730 $154 15-17 Days 8
Magnehelic® Pressure Gauge Analog 0-3.0" WC ISO 8 2625-11 11731 $147 1-3 Days 9
Quick Ship+ Only 6 left in stock
Magnehelic® Pressure Gauge Analog 0-4.0" WC ISO 8 2625-12 11732 $200 1-3 Days 10
Only 1 left in stock
Minihelic® Pressure Gauge Analog 0-0.5" WC ISO 8 2625-43 43432 $166 0-2 Days 11
In stock
Minihelic® Pressure Gauge Analog 0-1.0" WC ISO 8 2625-44 43433 $152 5-11 Days 12
Minihelic® Pressure Gauge Analog 0-2.0" WC ISO 8 2625-45 43456 $152 15-21 Days 13
Minihelic® Pressure Gauge Analog 0-3.0" WC ISO 6 2625-46 43457 $90 ..... 14
In stock
Minihelic® Pressure Gauge Analog 0-5.0" WC ISO 8 2625-47 43458 $152 15-21 Days 15
Photohelic® Pressure Gauge Analog 0-0.5" WC ISO 8 2625-13 11733 $890 15-21 Days 16
Photohelic® Pressure Gauge Analog 0-1.0" WC ISO 8 2625-14 11734 $889 15-21 Days 17
Photohelic® Pressure Gauge Analog 0-2.0" WC ISO 8 2625-15 11735 $1,025 15-21 Days 18
Photohelic® Pressure Gauge Analog 0-3.0" WC ISO 8 2625-16 11736 $1,104 1-3 Days 19
Quick Ship+ In stock
Type
Design
Scale Range
ISO Class
Item ordered before. Click on bagde to see the order.

Up to 30-day trial periods, free return shipping and on-site training available for qualified equipment.

Request demo from your product specialist or add note to your order or quote request.

Some ship in:
Usually Ships in:
Free shipping in contiguous USA
Custom-configured product. Contact Terra by phone, chat or email for a project-specific quote.
Custom-configured product. Contact Terra by phone, chat or email for a project-specific quote.
Select a product line for product summary
Product Details
Product Details
  • Available ISO Ratings: ISO 8
  • MAGNEHELIC and PHOTOHELIC differential pressure gauges maintain positive pressure necessary to block inrushing contaminants
  • Meets the requirements set forth in FED STD 209E
  • Incorporates an exclusive MAGNEHELIC Principle that eliminates wear, backlash, and hysteresis
  • This system avoids wear and physical contact, which might destroy the accuracy and sensitivity of the instrument
  • Measure and control both positive and negative low air or gas pressures
  • Provide an ideal way of monitoring and controlling the positive pressure differential required for cleanrooms
  • Enable you to meet ISO/FED STD 209E regarding cleanroom pressure
  • Ideal for measuring differential pressure in glove boxes and air flow in exhaust hoods
  • MAGNEHELIC Principle ensures wear-free accuracy within 2% of full scale
  • Applicable when gauging air filters, monitoring air conditioning systems, and measuring static air pressure and air vehicles

ISO Class: ISO 8

Unit of Measure: of 1

Features & Benefits

Features & Benefits

Learn More: Air Filter Gauges

Selecting the Proper Air Filter and Air Filter Gauge

Air Filters are incorporated into the ventilation system of a cleanroom to remove an extremely wide variety of contaminants from the air, including particles smaller than a micron (.000039"). Because variables involved in such ventilation systems vary radically—depending on the exact cleanliness standard, size of facility, rate of ventilation and many other factors—filter selection must be made by a qualified engineer in cooperation with the filter manufacturer.

Once a filtering system has been selected, one problem remains: how to judge when the filter has reached its effective lifespan. Because of the wide variation in the types and concentrations of contaminants in the air being filtered, length of service and visual inspections are an unreliable guideline. The most widely used method of determining when a filter needs to be serviced or replaced is to measure the pressure drop across the filter by means of an air filter gauge.

The Function of an Air Filter Gauge

An Air Filter Gauge measures pressure drops across the filter in order to determine whether or not the filter is operating within its design range of effective use. This is not the same as measuring filtering efficiency. Filter efficiency has to do with the ability of the filter to remove particulate matter from the air stream, and is generally measured in precisely controlled tests that vary according to the type of filter.

One method is to compare the weight of a carefully compounded dust mixture trapped in the filter with the weight of the dust released. Another method, originated by the NBS/NIST, compares the opacity of the dust collected on filter paper from two air samples of equal flow rate, one of which is filtered air. The efficiency of the filter is thus evaluated on the basis of the dust spots. A third method measures a resistance of DOP (Dioctyl-phthalate) smoke, a homogeneous aerosol of 0.3 micron size, to test a special class of high efficiency filter.

Although efficiency tests vary, the operating life of a filter is always determined by the amount of particulate dust it can hold, which in turn is related to the resistance across the filter that develops as more and more particles accumulate. An air filter gauge, by sensing the differential in static pressure across an air filter, thus permits the air filter to be used to its maximum dustholding capacity as determined by the filter manufacturer. And by indicating when a filter needs servicing, an air filter gauge can avoid excessive resistance that could disturb the balance of the system, increase air leakage and, for some types of filter, begin to pass contaminants.

Recommended Resistances for Air Filters

All filter manufacturers supply technical data which indicate the initial resistance in inches of water column for the filter at its rated air flow, and a recommended resistance at which point the filter should be replaced or serviced. These values vary according to the type of filter. For most filters used in a cleanroom environment, however, the range between initial and replacement resistance is typically between .01 and .1" WC.

During air filter installation, air filter gauges hence provide the additional function of ensuring proper installation and proper air-flow design. The gauge should indicate a pressure resistance in conformance with the manufacturer's recommendations. If pressure is too low, the filter may be handling less than the rated air volume due to open bypasses or improper air balancing, incorrect installation or air leaks. If pressure is too high after initial assembly, the filter may be incorrectly installed or the system may be handling more than the rated air volume.

*Source: Dwyer Control & Guages

Products Compliant With Your ISO Rating

Provide Terra with your desired ISO rating. We will tailor the product to meet your rating and supply a certificate of compliance appended to your invoice, to be included in your compliance package. All certificates are archived in Terra's system for quick retrieval.
Products similar to this one
Other products you may find relevant
Buy Accessories

On a tight schedule? Choose FasTrak 24/7 Priority Service to help meet your critical schedule for Terra-manufactured products, either before or after your order is placed.*

  • FasTrak 24/7 provides a 24/7 commitment to meet the shipping date YOU specify, regardless of quoted lead times.
  • FasTrak 24/7 assigns a dedicated production team plus a dedicated senior expeditor working three shifts to meet your delivery specification.
  • FasTrak 24/7 guarantees* to meet the agreed-to specified ship date.

Call for pricing. FasTrak service fees cover costs of additional services only, without additional profit.

 * Terra's FasTrak services limited guarantee: to ship on the ESD or date specified OR to refund up to 100% of FasTrak charges. This guarantee covers no direct, special, consequential or other damages and is strictly limited to up to 100% of the amount paid for FasTrak service. When a specified ship date is missed due to factors outside Terra's control (vendor performance, deliveries by shipping companies, etc.) and random factors such as accidents, the credit of up to 100% of the FasTrak 24/7 may not apply. FasTrak service requested after order placement will be quoted and accepted based on available time remaining before required ship date.