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  1. Dew Point Meters

Testo 6721 Dew Point Switch

Humidity monitoring in compressed air down to -30°C.

Testo 6721 Dew Point Switch
Testo 6721 Dew Point Switch
Retired products cannot be ordered
The Testo 6740 Trace Humidity Sensor is the recommended replacement

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Part Number
  • 0555 6721
Manufactured
  • By Testo
Includes
  • FREE Ground Shipping on orders of $1,000 or more
  • FREE Lifetime Tech Support
Questions?
Call 1-800-884-4967 or email sales@instrumart.com. Open Mo-Th 8am to 5:30pm. Fr 8am to 5pm ET.
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Overview

Features

  • Detects moisture in compressed air systems
  • Measurement range -30 to 30°C (-22 to 86°F)
  • Optional alarm box available
  • Easy configuration with P2A software
  • Uses proven Testo humidity sensor
  • Mini DIN interface

Description

The Testo 6721 dew point switch measures the temperature pressure dew point (tpd) coming from refrigeration dryers or downstream in pneumatic machines and processes from -30 to 30°C (-22 to 86°F) up to 300 psi (20 bar). Moisture in compressed air lines can lead to expensive damage: icing, corrosion, water hammer, sticky and clogged materials. The Testo 6721 dew point switch can save time, money and system downtime by monitoring moisture and avoiding damage.

The Testo 6721 dew point switch uses Testo's proven RH sensor design for accurate temperature pressure dew point measurements. It's easily installed in dryer and compressed air lines via its 1/2" NPT threaded fitting.

The Testo 6721 dew point switch can be configured using the optional Testo P2A software via USB cable and the data port on the 6721 switch. The software can easily program, adjust and review the 6721 operating history while connected to a laptop or PC. The user can even save a "master" program file that provides easy "copy and paste" program replication for OEM requirements. An optional alarm box (0554 6722) provides visual confirmation of both pre and alarm conditions.

Testo 6721 Dew Point Switch Specifications

Feature Testo 6721
Measuring range -30 to 30°C (-22 to 86°F)
Accuracy ±4 K (-30 to -20°C)(-22 to -4°F)
±3 K (-20 to -10°C)(-4 to 14°F)
±2 K (-10 to 0°C)(14 to 32°F)
±1 K (>0°C)(>32°F)
Sensor Testo humidity sensor (with special trace humidity adjustment) and NTC temperature sensor
Process pressure Max. 20 bar (abs)(290 psi)
Process temperature 0 to 50°C (32 to 122°F)
Outputs 2x switches potential-free max. 30 V/0.5 A
Interface Mini-DIN interface (serial) for parameterization / adjustment / analysis via P2A software
Voltage supply 20 to 30 VAC/VDC

Documents

Documents

  • Testo 6721 Dew Point Switch Data Sheet PDF (738 KB)
  • Testo 6721 Dew Point Switch & P2A Software Manual PDF (984 KB)

Accessories

Power Supplies

Testo Power Supply
Testo Power Supply

Wall-mountable 110-240 VAC box power supply.

$235.00 $211.50
Testo DIN Rail Power Supply
Testo DIN Rail Power Supply

DIN rail mountable 90-240 VAC power supply.

$302.00 $271.80

Software

Testo P2A Software Package
Testo P2A Software Package

Parameterizing, adjusting and analyzing software with USB cable and adaptor.

$272.00

Accessories

Please consider these optional accessories.

Testo Measurement Chamber
Testo Measurement Chamber

Measuring Chamber for Testo Dew Point Transmitters .

$322.00 $289.80
Testo Cooling Coil
Testo Cooling Coil

Cooling coil for Measuring Chamber .

$347.00 $312.30
Testo RH Calibration Set
Testo RH Calibration Set

Perform quick checks or full calibrations for humidity probes.

$514.00 $462.60

Need Help? Call a Temperature engineer at 1-800-884-4967

We're open Mo-Th 8am to 5:30pm. Fr 8am to 5pm ET

Rhys D. headshot Rhys D.
Applications Engineer
Dwight M. headshot Dwight M.
Senior Applications Engineer
28 years at Instrumart
Luke M. headshot Luke M.
Applications Engineer
5 years at Instrumart
Shawn D. headshot Shawn D.
Senior Applications Engineer
20 years at Instrumart
David S. headshot David S.
Applications Engineer
Alex A. headshot Alex A.
Senior Applications Engineer
19 years at Instrumart
Ron J. headshot Ron J.
Temperature Engineering Lead
29 years at Instrumart
Rhys D. headshot Rhys D.
Applications Engineer
Dwight M. headshot Dwight M.
Senior Applications Engineer
28 years at Instrumart
Luke M. headshot Luke M.
Applications Engineer
5 years at Instrumart
Shawn D. headshot Shawn D.
Senior Applications Engineer
20 years at Instrumart
David S. headshot David S.
Applications Engineer
Alex A. headshot Alex A.
Senior Applications Engineer
19 years at Instrumart
Ron J. headshot Ron J.
Temperature Engineering Lead
29 years at Instrumart
Rhys D. headshot Rhys D.
Applications Engineer

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Testo 6721 Dew Point Switch
Testo 6721 Dew Point Switch
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