Page #2 of 17___________________________________________________________________________ M4581 – DPL4000
Product Description:
This device is used to measure very low dew points with high accuracy and excellent long-
term stability. It can be used across a wide range of temperatures and pressures, and it
measures dew point in a variety of non-corrosive gases including Nitrogen, Argon, Hydrogen,
and Sulfur Hexafluoride (SF6).
General Specifications:
-148°F to +32°F (-100°C to 0°C)
Optimal Measurement Range:
-112°F to -22°F (-80°C to -30°C)
Accuracy (Within Optimal Range):
Accuracy (Outside Optimal Range):
Operating Temperature Range:
-40°F to +140°F (-40°C to +60°C)
Operating Pressure Range:
Sensor Housing Classification:
Display Housing Classification:
Rechargeable NIMH Battery (included) or 4 “AA” Batteries
Battery Charger Input Requirements:
110-240 VAC/ 47-63Hz / 400mA
Run Time on Battery Power:
48 Hours – Continuous use / Up to 30 days - Data logging only
Dew Point /Frost Point, ppm & ppb (by volume), ppm (by weight)
Nine Possible Languages (See “Language” section)
2700 points, user-selectable measurement interval
Data Logging Interval Options:
1s, 5s, 15s, 30s, 1min, 5min, 15min, 30min, 1h, 3h, 12h
Logging Duration Options:
1min, 5min, 15min, 30min, 1h, 3h, 12h, 24h, 7d, 31d, Memory Full
Sensor Technology:
The dew point measurement is based on a capacitive thin film polymer. Water molecules in
the surrounding air or gas diffuse into the polymer layer through the permeable upper
electrode, which changes the capacitance of the sensor. Changes in capacitance can be
directly correlated to the quantity of water molecules in the gas.
Special Features:
The dew point sensor in the DPL4000 performs two functions that provide increased accuracy
and response time.
•Automatic Calibration – The sensor warms itself and performs an offset (zero point)
correction. This is performed automatically at start up and after every 45 minutes of
continuous use.
•Sensor Purge – This function evaporates all excess moisture molecules from the sensor to
significantly increase the response time when the sensor goes from a wet condition to a
dry condition. This is performed automatically at startup and after every 24 hours of
continuous use. A Sensor Purge will also be initiated automatically when the sensor
detects a large wet-to-dry environmental change.
Getting Started:
To begin taking measurements with the DPL4000:
