Terra Part # 1401-94
Usually ships in 1-3 business days

Want it faster ? Read about FasTrak

Only 4 left in stock
Terra Part # 1401-94
Usually ships in 1-3 business days

Want it faster ? Read about FasTrak

Only 4 left in stock
  • Mounts in dry boxes and other sealed enclosures.
  • Features extreme sensitivity--measures moisture volumes from 0.5 PPM to 23,000 PPM.
  • Includes LCD meter, recorder output, alarm relay and operator manual, controller, sensor and cable.
  • Monitors and displays dew/frost point between -80 and +20° C on LCD readout.  
  • EPROM is included for calibration (Electrically Erasable Programmable Read-Only Memory)
  • 120V 60 Hz.  Operating power
  • Operating temperature: -110°C to +70°C
  • DewWatch sensor requires calibration when ordered separately from the DewWatch controller; calibration can be performed after shipping, but for factory calibration, specify the controller serial number when ordering a replacement sensor.

Accessories: Humidity/Moisture Control Systems

Control Type: DewWatch

Unit of Measure: EA

Electrical Specifications: 120 V, 0.5 A, 60 Hz

Weight, Product: 8 Lbs

Dimensions, Product: 11"W x 6.5"D x 4"H

Weight, Shipping: 12 lb

Dimensions, Shipping: 14" W x 10" D x 8" H

Package Type: Box

Features and Benefits

Dew Watch


  • Monitors and displays dew/frost point between -80 and +20 degrees C on LED readout
  • Features extreme sensitivity—measures moisture volumes from 0.5 PPM to 23,000 PPM
  • Mounts in dry boxes and other hermetically sealed enclosures for accurate in-place moisture monitoring and control
  • Interfaces with Terra's Dual Purge™ System for completely automatic nitrogen purging
  • Panel mountable for continuous monitoring of cleanrooms and other controlled areas
  • Takes the guesswork out of moisture control while saving on nitrogen consumption!

No one has the time to attend to all of the factors involved in maintaining the desired humidity conditions inside an enclosed environment. Therefore, you need a nitrogen control system that will automatically regulate the gas purge to compensate for such operating variables as the size and condiion of the chamber, the frequency and duration of access, and changing ambient humidity levels.

The DewWatch™ meets these monitoring/control requirements—economically and reliably.

Maintains Consistent, Traceable Glove Box Environment—Automatically

The extreme sensitivity and precision of the DewWatch™ makes it suitable for your most demanding applications. It operates over the -80 to +20 degree C dew point range, which is equivalent to 0.5 PPMV to 23,000 PPMV in gases at 1 atmosphere.

In glove box applications, the DewWatch™ performs a dual function. The LED display provides a continuous readout of the dew/frost point inside the chamber in whichever scale range you order (see specifications below). More importantly, it operates with the Dual Purge™ System to precisely control the flow of nitrogen into the enclosure and maintain a preset dew point.

Simple, Reliable Operation

All you have to do is find out from your supplier or process engineer exactly what dew point you need to maintain, set the desired level , interface the unit with Terra's Dual Purge™ System and then let it do its job. The unit's quick response sensor, when properly installed inside the chamber, will deliver a quick readout of the internal dew point. The controller will allow the Dual Purge™ System to adjust the nitrogen flow to maintain this desired dew point within 2 degrees C (3 degrees C in the -80 to -65 degree C range) no matter how operating or ambient conditions may change.

Special Design Features for Versatile Applications

Each DewWatch™ unit is individually calibrated and consists of a control unit and a humidity sensor.

  • Standard Dew/Frost Point Range: -80°C to +20°C
  • Power: 120VAC, 50/60Hz
  • Operating Temp: 0°C to +55°C
  • Storage Temp.: -20°C to +70°C
  • Warm-up Time: 3 min.
  • Output: 0 to 20mA, 4 to 20mA, 0 to 100mV, 0 to 2V
  • Case: General purpose, panel mount, RF shielded
  • Dimensions: 5.70" x 4.36" x 2.84" (144.8mm x 110.7mm x 72.1mm)
  • Weight: 1.65 lbs. (748 g)
  • Type: Aluminum Oxide Moisture Sensor Element
  • Calibrated Range: -80°C to +20°C
  • Pressure Rating: 5000 psig
  • Operating Temp.: -110°C to +70°C
  • Storage Temp.: 70°C max.
  • Flow Rate: 10,000 cm/sec. linear velocity max. in gas phase.
  • Calibration Accuracy: ± 2°C in range of -65°C to +20°C, ± 3°C in range of -80°C to -65°C
  • Calibration Data: Calibration Data: On EPROM (Electrically Erasable Programmable Read-Only Memory)

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.

You need at least 2 products to compare Compare Clear All
Compare Products