Schmidt DHT-2 User manual

Moisture Meter
Model DHT-2
Edition DHT-2.01-E
Operating Instructions
Valid as of: 01.12.2016• Please keep the manual for future reference!
S C H M I D T
c o n t r o l i n s t r u m e n t s

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Contents
1 Warranty and Liability .............................................................................................. 3
1.1 Notices within the Operating Instructions............................................................... 3
1.2 Responsibilities of the Operating Company ........................................................... 3
1.3 Responsibilities of the Personnel ........................................................................... 3
1.4 Informal Safety Measures ...................................................................................... 4
1.5 Training of the Personnel ....................................................................................... 4
1.6 Intended Use.......................................................................................................... 4
1.7 Dangers in Handling the Device............................................................................. 4
1.8 Copyright................................................................................................................ 4
1.9 EU Declaration of Conformity and WEEE Registration.......................................... 4
2 Available Models....................................................................................................... 5
2.1 Specifications ......................................................................................................... 5
2.2 Delivery Includes ................................................................................................... 5
2.3 Optional Accessories ............................................................................................. 5
2.4 Unpacking .............................................................................................................. 6
3 Operation................................................................................................................... 6
3.1 Notes Before Starting Measurement...................................................................... 6
3.2 Operating Elements ............................................................................................... 6
3.3 Battery Insertion and Replacement........................................................................ 6
3.3.1 Switch-On......................................................................................................... 7
3.3.2 Switch-Off......................................................................................................... 7
3.3.3 Inserting the Measuring Electrode.................................................................... 7
3.4 Measuring Procedure ............................................................................................ 8
3.4.1 Conversion Charts............................................................................................ 9
3.5 Verification of Calibration ..................................................................................... 14
4 Service and Maintenance....................................................................................... 14
5 Cleaning................................................................................................................... 14
6 Verification Interval ................................................................................................ 14
7 Correspondence ..................................................................................................... 14
8 Repairs..................................................................................................................... 15

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1 Warranty and Liability
In principle, the supply of the device is subject to our “General Conditions of Sale and
Delivery.” These have been provided to the operating company on conclusion of the
contract, at the latest.
Warranty:
- SCHMIDT moisture meters are warranted for 12 months.
Parts subject to wear, electronic components and measuring springs are not covered by
the warranty. No warranty or liability will be accepted for bodily injury or property damage
resulting from one or several of the following causes:
- Misuse or abuse of the device.
- Improper mounting, commissioning, operation and maintenance of the device
(e.g. verification interval).
- Operation of the device if any safeguards are defective or if any safety and protection
precautions are not properly installed or not operative.
- Failure to comply with the notices in the Operating Instructions regarding transport,
storage, mounting, commissioning, operation, maintenance and setup of the device.
- Any unauthorized structural alteration of the device.
- Insufficient inspection of device components that are subject to wear.
- Opening the device or improper repair work.
- Disasters caused by the effects of foreign objects or by force majeure.
1.1 Notices within the Operating Instructions
The fundamental prerequisite for the safe handling of this device and its troublefree opera-
tion is the knowledge of the basic safety notices and safety instructions.
These Operating Instructions provide essential information to ensure the safe operation of
the device.
These Operating Instructions, in particular the safety notices, must be observed by any
person who works with the device. In addition, the local applicable rules and regulations
for the prevention of accidents must be complied with.
The representations within the Operating Instructions are not true to scale.
The dimensions given are not binding.
General indications of direction, such as FRONT, REAR, RIGHT, LEFT apply when view-
ing the front of the device.
1.2 Responsibilities of the Operating Company
In compliance with the EC Directive 89/655/EEC, the operating company agrees to only
permit persons to work with the device who:
- are familiar with the basic regulations on industrial safety and accident prevention and
who have been trained in handling the device.
- have read and understood the chapter on safety and the warning notices in these
Operating Instructions and have confirmed this with their signatures.
- are examined regularly on their safe and conscientious working method.
1.3 Responsibilities of the Personnel
All persons who work with the device agree to perform the following duties before starting
work:
- to observe the basic regulations on industrial safety and accident prevention.
- to read the chapter on safety and the warning notices in these Operating Instructions and
to confirm with their signatures that they have understood them.

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1.4 Informal Safety Measures
The Operating Instructions must always be kept on hand where the device is operated.
Apart from the Operating Instructions, the generally and locally valid regulations on acci-
dent prevention and environmental protection must be provided and complied with.
1.5 Training of the Personnel
Only trained and instructed personnel is permitted to work with the device. The responsi-
bilities of the personnel must be clearly defined for mounting, commissioning, operation,
setup, maintenance, and repair. Trainees may only work with the device under the super-
vision of experienced personnel.
1.6 Intended Use
The device is intended exclusively to be used as a moisture meter. Any other use or any
use exceeding this intention will be regarded as misuse. Under no circumstances shall
HANS SCHMIDT & Co GmbH be held liable for damage resulting from misuse.
The intended use also includes:
- Complying with all notices included in the Operating Instructions and observing all
inspection and maintenance works.
1.7 Dangers in Handling the Device
The device was designed according to the state of the art and the approved safety stan-
dards. Nevertheless, its use may cause serious or fatal injury to the user or third persons,
and/or an impairment of the device or of other material assets.
The device may only be applied:
- For its intended use in a faultless condition with regard to the safety requirements.
- Malfunctions that could impair safety must be remedied immediately.
- Personal protective equipment must be used according to the EC Directive 89/686/EEC.
The device must not be operated in potential explosive areas and must not
come into contact with aggressive substances.
1.8 Copyright
The copyright on these Operating Instructions remains with the company
HANS SCHMIDT & Co GmbH.
These Operating Instructions are intended for the operating company and its personnel
only. They contain instructions and notices that may only be reproduced on the prior writ-
ten permission of
HANS SCHMIDT & Co GmbH
and under indication of the complete reference data.
Violations will be prosecuted.
1.9 EU Declaration of Conformity and WEEE Registration
In compliance with the EU Directive 2004/108/EG
HANS SCHMIDT & CO GmbH is registered in compliance with
the German Electrical and Electronic Equipment Act (ElektroG).

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2 Available Models
DHT-2
2.1 Specifications
Application Area: Direct readings for:
(Relative Moisture Content) Wool, cotton, rayon, hemp, jute, paper, linen, nylon,
polyacrylic, polyester, 10 fabric blends
Comparison measurement for other materials:
1 - 100 scale for comparison with 20 conversion charts
(Room Temperature) -30° to 70° Celsius (optional)
(Air Humidity) 5% to 95% RH (optional)
Display: LCD, 0.1 resolution
Accuracy: 1% (of full scale)
Repeatability: 0.3%
Power Supply: 9V E block battery, low-battery indicator
Auto Power Off: After approx. 2 min.
Weight: 1650 g (complete set incl. carrying case)
Dimensions: 200 mm x 95 mm x 40 mm (LxWxH)
2.2 Delivery Includes
Textile moisture meter with carrying case
1Connecting cable 1m length ID no.: 50400M
1Probe holder For inserting the different electrodes ID no.: 50404M
1Needle electrode For measuring spools, bobbins and
hanks of yarn
2-pin probe, 100mm long ID no.: 50414M
1Needle electrode For measuring spools, bobbins and
hanks of yarn
8-pin probe, 80mm long ID no.: 50418M
1Operating Instructions
2.3 Optional Accessories
1Needle electrode For measuring bales or rolls of fabric, yarn, etc.
300mm long ID no.: 50412M
1Roller electrode For measuring moving webs of material
27mm roller diameter. ID no.: 50416M
1 surface electrode For measuring fabrics, surface Ø 30 mm ID no.: 50426M
1Set of calibration electrodes comprising 2 calibration electrodes
of different calibration values for verification and calibration of
the moisture meter. ID no.: 50422M
Calibration Certificate optionally available for the calibration
electrodes.
1Temperature and air humidity probe for determining the absolute
room temperature in °C and the room air humidity in % RH
170 mm length ID no.: 50428M
2Different calibration reports are available for the moisture meter:
a) Manufacturer‘s standard calibration report in English
b) Calibration report in English using SIT certified electrodes
(SIT: Italian Calibration Institute, similar to DKD in Germany).

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2.4 Unpacking
Unpack the moisture meter and inspect it for any shipping damage.
Notices of defect must be filed immediately, in writing, at the latest within 10 days on
receipt of the goods.
3 Operation
3.1 Notes Before Starting Measurement
Have you read and understood the Operating Instructions, in particular
Chapter 1 “Basic Safety Notices”? You are not permitted to operate the
moisture meter before doing so.
Before working with the instrument you must put on your personal protective
clothing, if necessary. For example, eye protectors, gloves, etc.
3.2 Operating Elements
3.3 Battery Insertion and Replacement
The moisture meter is delivered with a 9V E block battery inserted.
If “Low Battery” is indicated on the DISPLAY, the battery must be replaced immediately.
Operating the instrument with a low battery may cause measurement errors.
To insert the new battery:
- Open the BATTERY COMPARTMENT on the rear side
of the instrument.
- Insert a 9V battery (E block) into the
BATTERY COMPARTMENT.
Please ensure proper polarity.
- Close the BATTERY COMPARTMENT.
Used batteries must be disposed of in compliance with local regulations.
If the instrument will not be used for a longer period of time, the battery
should be removed.
DISPLAY
UP key DOWN key
BNC CONNECTOR
PS2 CONNECTOR
fig. 3.2

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3.3.1 Switch-On
- Press the key until the DISPLAY shows the measuring
range that was last selected.
3.3.2 Switch-Off
Auto Power Off:
- The moisture meter switches off automatically after about 2 minutes of non-use.
3.3.3 Inserting the Measuring Electrode
- Select the proper ELECTRODE for your application.
- Insert the ELECTRODE into the receptacles on the top of the PROBE HOLDER
(fig. 3.3.3) and screw on the RETAINING RING.
- Plug in the CONNECTING CABLE at the BNC connectors of the ELECTRODE and
the DHT-2 moisture meter (fig. 3.3.3b).
PROBE HOLDER
ELECTRODE
RETAINING RING
fig. 3.3.3a
ELECTRODE
CONNECTING CABLE
DHT-2
fig. 3.3.3b

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3.4 Measuring Procedure
General information:
The measuring principle of the DHT-2 moisture meter is based on the electrical conductiv-
ity of the material which always bears a fixed relation to the moisture.
The moisture meter displays direct readings for the materials listed in the table below. For
other materials, note the reading on the upper 0 - 100 scale and then refer to the conver-
sion charts in Chapter 3.4.1 to convert the absolute reading into an accurate measurement
of percent moisture.
Display Measuring Range
CENT.
DEG.
Room temperature
Requires use of electrode no. 428 (optionally available)
% R.H. Room air humidity
Requires use of electrode no. 428 (optionally available)
0 - 100 1 - 100 scale
WOOL Wool (Wo)
RAYON Rayon (Zw)
COTTON Cotton (Bw)
HEMP Hemp (HA)
JUTE Jute (JU)
PAPER Paper
FLAX YARN Flax Yarn (FL (Li))
NYLON Nylon
ACRYL Polyacrylic (PA)
POLYESTER Polyester (PES)
50WO - 50ZW 50% Wool (Wo) - 50% Rayon (Zw)
60BW - 40PES 60% Cotton (Bw) - 40% Polyester (PES)
70PAC - 30WO 70% Polyacrylic (PAC) - 30% Wool (Wo)
67PAC - 33BW 67% Polyacrylic (PAC) - 33% Cotton (Bw)
70PES - 30WO 70% Polyester (PES) - 30% Wool (Wo)
70PES - 30ZW 70% Polyester (PES) - 30% Rayon (Zw)
67PES - 33BW 67% Polyester (PES) - 33% Cotton (Bw)
50PES - 50BW 50% Polyester (PES) - 50% Cotton (Bw)
50PES - 50ZW 50% Polyester (PES) - 50% Rayon (Zw)
50PES - 50PAC 50% Polyester (PES) - 50% Polyacrylic (PAC)
Requirements:
- Proper electrode inserted and connected to DHT-2 as described in Chapter 3.3.3.
To take measurements:
- Press the key to switch on the DHT-2 moisture meter.
The DISPLAY shows the measuring range that was active the last time the instrument
switched off.
- Press the or key for about 2 sec. to select the next or previous
measuring range (as listed in the table above).

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3.4 Measuring Procedure (Cont.)
- Insert the ends of the selected ELECTRODE into the TEST MATERIAL (fig. 3.4).
The DISPLAY shows the measured moisture content of the TEST MATERIAL.
fig. 3.4
3.4.1 Conversion Charts
Relative
moisture [%]
Acetate Yarn (CA)
ELECTRODE
CONNECTING CABLE
DHT-2

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3.4.1 Conversion Charts (Cont.)
Relative
moisture [%]
Sisal Yarn
Relative
moisture [%]
55% Polyester (PES) - 45% Rayon (Zw)
Relative
moisture [%]
33% Rayon (Zw) - 67% Cotton (Bw)
Relative
moisture [%]
40% Cotton (Bw) - 60% Flax Yarn (FL / Li)
Relative
moisture [%]
40% Polyacrylic (PAC / PAN) - 60% Wool (Wo)