Alpha Moisture Systems DS1200-PDT User manual

Model DS1200-PDT Dewpoint Hygrometer
-40 / +30°Cdp (50bar maximum pressure)
-60 / +20°Cdp (50bar maximum pressure)
User Manual
Englis

Model DS1200-PDT - Dewpoint Hygrometer
CERTIFICATE No. FM35600
BS EN ISO 9001:2015

Document Reference:
2249 - Issue 3
21/06/2018
Model DS1200-PDT Dewpoint Hygrometer
User Manual
©Alpha Moisture Systems Ltd.
This is a step by step instrucon manual to help you successfully set up
correctly the Model DS1200-PDT Dewpoint Hygrometer before use.
This manual should be kept with the instrument for future reference.
You must observe the safety informaon on pages 6 and 10 before
installaon.
Please read t is manual carefully from t e start.

4
Model DS1200-PDT - Dewpoint Hygrometer
Index
General Overview 5
Safety Informaon 6
Model DS1200 Control-Display Front Arrangement 7
PDT Arrangement 7
Features of the Model DS1200-PDT 7
DS1200 Mounng 8
Installing the Instrument into a Panel 8
Wiring DS1200 Power Supply 8
PDT Transmier Cable 8
Alarm Cable 9
Analogue Output Cable 9
DS1200 Connecons 9
PDT Connecons 10
Installing the Model PDT in a Air/Gas Sampling System 10-11
Piping Installaon Schemac 11-12
Installing and Commissioning the Model PDT Transmier 13
Seng the Alarm Trip Points 13
Dimensions 14
Speci caons 15-16
Contact Informaon 17

5
Model DS1200-PDT - Dewpoint Hygrometer
General Overview
Thank you for purchasing the Alp a Moisture Systems Model DS1200-PDT Dewpoint
Hygrometer.
We hope that you will agree that this instrument is easy to set up and very user friendly to
operate giving you reliable and accurate measurements quickly and efficiently.
The Model DS1200-PDT Dewpoint Hygrometer is a global popular choice of Dewpoint
Hygrometers (trace moisture analysers) that work on a basis of polymer sensors and are
used for the determinaon of moisture in most gases in the dewpoint or RH range.
They consist of a separately installed measuring cell of high grade stainless steel (available
through your local distributor or Alpha Moisture Systems where there is no distributor for
your locaon) a Transmier and Control-Display, that can be integrated in a Gas Handling
System*, and an in-line process source.
The Model DS1200-PDT Dewpoint Hygrometer is installed as a single channel analyser.
For addional accessories and parts, or technical help for the Model DS1200-PDT, or any
other Alpha Moisture Systems products, please contact your local distributor or contact
Alpha Moisture Systems - see last page for details.
*Alp a Moisture Systems can manufacture to your specificaons a Gas Sample System to
suit your exact requirements, please contact your local distributor for more informaon.
Visit our website www.amsystems.co.uk for more informaon.

6
Model DS1200-PDT - Dewpoint Hygrometer
Safety Informaon
The DS1200-PDT has been designed to be connected to hazardous electric voltages and
must be protected by a 5amp fused plug to the mains/AC supply.
Check to establish that all wiring and connecons are not damaged. If damage is
observed to any electrical wiring, connecons or damage to the apparatus they must not
be connected to the mains/AC supply but returned to your local distributor for rec caon.
Warnings
Risk of electric shock - Do not open any part of the enclosures of the Model DS1200-PDT
whilst connected to the mains/AC supply.
Do not connect the Model DS1200-PDT to the mains/AC supply unl all other connecons
and pipework is secure and have been tested.
Ignoring this safety informaon could result in severe personal injury and/or mechanical
damage to the Model DS1200-PDT.
The product speci caons must not be exceeded at anyme, as this may cause personal
injury, damage to the instrument and sensor or cause risk of re.
Do not connect the Model DS1200-PDT to any other device that is not recommended in
this manual.
Ensure that the Model DS1200-PDT does not come into direct contact with water or any
other liquids. See IP/NEMA protecon in the product speci caons.
To avoid the risk of electric shock, risk of damage or re, these safety instrucons and
guidelines must be followed. Only quali ed personnel/technicians should install these
units to the mains/AC supply and connecng pipework to ensure it is completely safe by
tesng and recording before use.
It is the responsibility of the customer to ensure safe working condions especially working
with hazardous gases and liquids. Leak tests should be carried out periodically by quali ed
personnel.
Safe Isolaon
Switch off at the mains/AC socket and remove the plugs before any maintenance is carried
out by a quali ed person. Always test components with an approved voltage meter before
handling to ensure it is completely dead.
YOU MUST ALSO READ THE WARNING INFORMATION ON PAGE 10.

7
Model DS1200-PDT - Dewpoint Hygrometer
Model DS1200 Control-Display Front Arrangement
LED Alarm Indicators. Sounders
can also be connected at the rear
of the unit. See page 9 diagram.
Menu
navigaon
keys
Con rmaon
key
PDT Transmier Arrangement
See Pages 14 - 16 for dimensions, diagrams and tec nical specificaons
Permeable
Sensor Guard
SUPPLIED WITH A CERTIFICATE OF CALIBRATION
Iden caon Label
with Serial Number
Cable
Connecon
Features of t e Model DS1200-PDT
DS1200 Control-Display
• The Model DS1200-PDT is a single channel analyser.
• DS1200 has a 4-digit 14 segment LED display
• DS1200 has 2 adjustable Alarm set points and an analogue output. See pages 9 and 13.
• DS1200 has mA Output (terminals 11 and 12)
• Universal Voltage Supply (terminals 31 & 32)
PDT Transmier
• Ranges available: -40 to +30°C or -60 to +20°C (-40 to +86°F or -76 to +68°F) Dewpoint
• Two wire 4-20mA transmier for connuous measurement of moisture in a process
gas or compressed air
• Reliable, accurate and easy to install

8
Model DS1200-PDT - Dewpoint Hygrometer
DS1200 Mounng
• Only technicians who are familiar with the technical terms, warnings, and instrucons
in the manual and who are able to follow these should connect the DS1200.
• Should there be any doubt as to the correct handling of the DS1200, please contact
your local distributor.
• Mounng and connecon of the DS1200 should comply with the naonal legislaon
for the mounng of electric materials, i.e. wire cross-secon, protecve fuse, and
locaon.
Descripons of Input / Output and supply connecons are shown in the block diagram
on page 9 and the instrument top label.
• The maximum size of the protecve fuse is 5A and, together with the power switch, it
should be easily accessible and close to the DS1200. The power switch should be
marked with a label indicang it will turn OFF the voltage to the DS1200.
• To be mounted in front panels. The included rubber packing must be mounted between
the panel cutout and the display front to obtain IP65 (NEMA 4) ingress protecon.
Installing t e Instrument into a Panel
• Make a cut-out in the donor panel 92.0/92.8 x 45.0/45.6mm (DIN 43700).
• The maximum panel thickness is 10mm and, if an effecve IP65 weatherproof seal is
required, the minimum recommended panel thickness is 1.6mm.
• Pass the instrument cabinet through the cut-out in the donor panel and slide the panel
clamp over the instrument, from the back.
• Turn the Red panel clamp screws unl the instrument is clamped in posion. The
screws must be ghtened sufficiently to affect a seal between the front of the donor
panel and the back of the instrument bezel, but never over ghtened to the point of
fracturing the panel clamp or instrument case.
NOTE Wires are retained by screws. Ensure t at t e exposed secon of t e wire is fully
inserted and t at no loose strands are exposed.
Wiring DS1200 Power Supply
• Connect the power supply cable to the 2 terminal block marked 31 and 32 no polarity.
• The power supply should be 22 to 253 VAC @ 50/60Hz or 20 to 300 VDC.
PDT Transmier Cable
• Connect the transmier cable to connector pins 45 and 46, ensuring that the red wire
connects to pin 46. See Diagrams on pages 9 and 10.
Observe that the cage is securely clamped onto the bootlace ferrules on the cable
provided.
• Route the sensor cable to the intended site of the sensor.
Note : - Do not install t e transmier at t is me.
Wait unl t e commissioning stage as described later

9
Model DS1200-PDT - Dewpoint Hygrometer
Alarm Cable
• Make the appropriate connecons, nong the normally open and normally closed relay
contact posions.
Analogue Output Cable
• Make the appropriate connecons, ensuring that the correct polarity and the
maximum load speci caon is strictly observed.
DS1200 Connecons:
BLUE wire from the
PDT Cable connected
to pin 45 on the rear
of DS1200
RED wire from the
PDT Cable connected
to pin 46 on the rear
of DS1200
Polarity is universal
and can be wired +/-
or -/+

10
Model DS1200-PDT - Dewpoint Hygrometer
M12 connector plug
If no connecon cable is ordered, the sensor will be supplied with a M12 connector plug.
The user can connect the supply and signal cables as indicated in the connecon diagram
below.
PDT Connecons:
Pin 2 to Pin 45 on
DS1200
Pin 3 to Pin 46 on
DS1200
Installing t e Model PDT in a Air/Gas Sampling System
Warning: D n t exceed a pressure f 50 bar.
Observe the o erating ranges of the sensor. The robes are damaged if they are
overheated.
Observe maximum storage and trans ort tem erature as well as maximum
o erating tem erature (i.e. rotect the instrument from direct sunlight).
Imp rtant: Before installation, bleed com ressed air systems in order to remove
condensate and articles to avoid contamination.

11
Model DS1200-PDT - Dewpoint Hygrometer
Installing t e Model PDT in a Air/Gas Sampling System - Connued
Piping Installaon Sc emac
The piping installaon schemac diagram below shows all components, which could be
used in a dry gas measurement applicaon although not all the items shown will be
required for every installaon.
The flow rate, although not crical to the sensor measurement, should be low enough
to avoid abrasion to the sensor surface without being so low as to extend the system
response me to an unacceptable level. In general, a flow rate of between 2 and 3
litres/minimum at NTP will give the right balance.
The sensor is a variable capacitor, which is directly affected by changes in paral pressure
of water vapour. These changes are proporonal to the dew/frost point temperature.
The measuring transmier can be installed directly into the process line or ducng, but
this can create problems with access for maintenance and calibraon. It is for these
reasons that we recommend that the transmier be installed in a bypass, fast loop or
total loss sample system where the transmier is accessible without interrupng the
main process flow line.

12
Model DS1200-PDT - Dewpoint Hygrometer
Piping Installaon Sc emac - Connued
1) Sample Isolaon Valve - This is a recommended item as it allows access to the
sample system without interrupng the main process line.
2) Sample Tube – This should be stainless steel for dry air or gas applicaons but copper
or carbon steel can be used where weer gases are to be measured. If any secon of
the sample tube must be flexible then PTFE should be used. In most cases, 3mm OD
(1/8”) is sufficient as it provides good system response me within minimum flow.
6mm OD (1/4”) tube can be used where pressure drops across the 3mm tube are too
high.
3) Filter Unit – A lter unit is recommended when the samples are likely to contain
parculate maer. If the air/gas sample contains heavy hydrocarbon condensate, the
lter must be of the coalescing type with a drain. The lter unit should be posioned
as close to the sample point as praccal.
4) Pressure Reducon Valve or Pressure Regulator – If the sample is to be measured at
atmospheric pressure then the valve 4A should be ed and 4B omied from the
system. If the sample is to be measured, at full line pressure and the exhaust vented
to atmosphere, then valve 4B should be ed and 4A omied from the system. If
measurements are to be taken at full line pressure and the sample is to be returned
to a part of the main line or a vent, which is at a pressure higher than atmospheric,
and the input to that line needs a controlled pressure then both 4A and 4B will
be required.
5) Sample Pressure Gauge – This is not a crical part of the moisture measurement
but may be required if Dew/Frost point measurements are to be made at higher
than atmospheric pressure.
6) Measuring Transmier – Model PDT with Connector, General Arrangement.
7) Transmier Holder – Transmier Holder General Arrangement.
8) Desiccant C amber – This item is required when the sampling is to be intermient.
When installed it prevents the ingress of wet air to the sample system, while the
sample is not flowing, improving the response me.
9) Flow Control Valve – This can be a separate item or combined with the flow indicator.
10) Flow Indicator – The recommended minimum sample flow is 2 to 3 litres per minute.
11) Sample Ex aust – The exhaust can be vented to atmosphere or returned to the
process line as discussed above.
All addional components are available t roug your local distributor.

13
Model DS1200-PDT - Dewpoint Hygrometer
Installing and Commissioning t e Model PDT Transmier
It is advisable to carry out an inial purge of the sample loop, before installing the
transmier, in order to reduce the possibility of sensor damage on start-up.
Refer to the sample system schemac on page 11. Open the inlet isolaon valve slowly,
unl a small flow of air/gas at atmospheric pressure flows through the inlet pipe work to
the transmier holder and exhausts through the sensor entry port of the transmier
holder.
Allow this purge to connue for about 15 to 20 minutes to remove any residual moisture
from the sample pipe work and components.
Close the inlet isolaon valve and install the transmier into the transmier holder. Locate
and secure the cable connector in posion on the transmier. Use the locking screw in
order to affect a weatherproof seal.
Open the inlet valve slowly again and, by opening all valves aer the transmier holder,
allow a low-pressure purge through the whole sample system. (Note. If a closed by-pass
loop is installed, this secon of the procedure is not possible).
Set the required pressures and flows within the sample loop.
This completes the installaon and commissioning but, on inial start-up, it could take
several hours for the system to reach equilibrium.
Seng t e Alarm Trip
Points
To acvate the quick alarm
sengs screen press either the ”
” or ” ” buons, while the
DS1200 is displaying the moisture
level.
The DS1200 will flash the “F.SET”
message followed by a selecon
menu for Alarm 1 or 2 relay. Scroll
to the required alarm and press
the “OK” buon.
The DS1200 then displays the
message “SETP” momentarily
before displaying the current set
point in % of scale.

14
Model DS1200-PDT - Dewpoint Hygrometer
Dimensions
DS1200
PDT Transmier
PDT Transmier Holder Model SH-PDT Flow T roug Sample Cell
3 (0.125)
34ø (1.34 dia)
54 (2.125)
15 (0.6)
58 (2.28)
68 (2.68)
10 (0.4)
43 (1.7)
43 (1.7)
44 (1.73)
54 (2.125)
2 Mounting Holes 5.5ø (0.22 dia.)
43 (1.7)
Note: The Assembly is shown with 1/4@ OD tube ngs. The dimensions across the tube ngs will
vary for all other size ngs.

15
Model DS1200-PDT - Dewpoint Hygrometer
Specificaons
DS1200
• Temperature operang range = -20°C to +60°C (-4°F to 140°F)
• Power supply = 20 – 300 VDC, or 22 to 253 VAC 50 – 60 Hz
• 3.2W internal power consumpon
• 3.5W maximum power consumpon
• Isolaon voltage test / operaon = 2.3KVAC / 250 VAC
• Signal to noise rao = Min 60dB (0-100kHz)
• Display Response me (0-90%, 100 to 10%) = 0.4s.
• Wire size, pin 45 & 46 (max) = 1 x 1.5mm2 stranded wire
• Wire size, others (max) = 1 x 2.5mm2 stranded wire
• Relave Humidity = < 95% RH
• Dimensions (HxWxD) = 48 x 96 x 120mm
• Cut out dimensions = 44.5 x 91.5mm
• Ingress Protecon = (Front panel) IP65/NEMA4
• Weight = 230g
• Input
oFrom Model PDT
oError detecon = Cable loop break
• Display
oDisplay Readout = PDT range
oScrolled error display
• Current Output
oProgrammable signal ranges = 0…20 or 4…20mADC (Factory set)
oLoad (max) 20mA / 800Ω / 16VDC
oLoad stability ≤ 0.01 % of span / 100 Ω
• Relay
oRelay funcon = setpoint
oHysterisis 1% of range
oMax voltage = 250 VRMS
oMax Current = 2A /AC
oMax AC power = 500VA
oMax current at 24 VDC = 1A

16
Model DS1200-PDT - Dewpoint Hygrometer
Output Signal : 4 to 20mA Linear to its range.
Operang Voltage : 10V - 30V DC.
Factory calibraon : Supplied with Cer cate of Calibraon traceable to NPL/NIST
Accuracy : ± 2°C dewpoint (NPL / NIST traceable)
Temperature compensaon : Temperature compensated for operang range.
Operang temperature : -30…70°C (ideal 0…50°C)
Storage Temperature : -40…80°C
Operang Pressure : From 1kPa (0.01 barA) to Maximum 5,000kPa (50 barA)
Sample Flow Rate : Independent but ideally 2 to 3 litres per minute.
Max: 25 litres/min.
Connecon : M12, 5-pole
EMC : DIN EN 61326
Transmier Enclosure : Zinc alloy, PC, ABS
Sensor Protecon : 316 Sintered stainless steel lter - 50 micron
Weatherproof Classi caon : IP65/NEMA4 when Connector mated to Transmier.
Mechanical Connecon : G 1/2”
Mechanical Warranty : 12 months in case of faulty workmanship and defecve parts.
Specificaons PDT Transmier
Specificaons PDT Transmier Holder
High Grade 316 Stainless Steel - Part Number SH-PDT

17
Model DS1200-PDT - Dewpoint Hygrometer
Notes:
Contact Informaon
Head Office:
Alp a Moisture Systems
Alpha House
96 City Road
Bradford
West Yorkshire
BD8 8ES
United Kingdom
Tel: [phone]
Fax: [phone]
Email: [e-mail]
Web: www.amsystems.co.uk
Office Opening Hours:
Monday - T ursday
8.30am - 5.30pm GMT
Friday
8.30am - 5.00pm
Saturday and Sunday - Closed
Distributor Informaon: