Vaisala DRYCAP DMT143 User manual

Procedure Instruction 1(16)
Field Tech Manual for DMT143-series
2018-04-06
Vaisala Instruments
Document Revision
Rev. Date Creator
Status
Reason
A 4/6/2018 JAMM First revision
General Product info
Introduction to DM 143
Vaisala DRYCAP® Dewpoint ransmitter DM 143 is a small and lightweight dewpoint transmitter
suitable for a wide range of OEM applications. DM 143 is easy to install and the mechanics have been
designed for harsh environments requiring protection against dust, dirt and splashed water.
here are two variants of the DM 143 transmitter, DM 143 and DM 143L.
DM 143 with DRYCAP® 180D sensor
•either G1/2” ISO228/1 or NP 1/2” mechanical connection
•measurement range -70 ... +60 °C (-94 ... +140 °F)
•operating pressure up to 50 bara (725 psia)
•voltage (V) or current (mA) analog output
DM 143L with DRYCAP® 180M sensor
•G1/2” ISO228/1 mechanical connection
•measurement range -70 ... + 60 °C° (-94 ... +140 °F)
•operating pressure 0 ... 20 bara (0 ... 290 psia)
•current (mA) analog output
DM 143L with DRYCAP® 180S sensor
•G1/2” ISO228/1 mechanical connection
•measurement range -50 ... + 60 °C° (-58 ... +140 °F)
•operating pressure 0 ... 20 bara (0 ... 290 psia)
• current (mA) analog output

Procedure Instruction 2(16)
Field Tech Manual for DMT143-series
2018-04-06
Vaisala Instruments
o Table of Contents
General Product info ...............................................................................................................1
here are two variants of the DM 143 transmitter, DM 143 and DM 143L. .................1
o able of Contents .............................................................................................................2
Service policy.....................................................................................................................3
ools needed.....................................................................................................................3
Wiring.................................................................................................................................4
rouble Shooting..............................................................................................................5
4.1 Analog Output or Display does not match expected value................................................... 5
4.2 Measurement Reading bounces around .................................................................................. 5
4.3 Checking Error Messages with Service Port ............................................................................. 6
4.4 Checking Error Messages with Service Port ............................................................................. 8
4.5 Operational tests using USB Service Cable and Service Port................................................. 8
4.6 Changing Output Parameter and Channel information ......................................................... 9
4.7 Reset to factory ordered configuration .................................................................................. 10
4.8 Thread Types................................................................................................................................ 10
Maintenance....................................................................................................................11
5.1 Visual Check................................................................................................................................ 11
5.2 Cleaning the HUMICAP sensor ................................................................................................ 11
Spare or Replacement parts available for customers................................................12
CALIBRATION AND ADJUSTMENT...........................................................................13
DMT143 Order Codes ......................................................................................................15
Calculate mA and Process Values ....................................................................................16

Procedure Instruction 3(16)
Field Tech Manual for DMT143-series
2018-04-06
Vaisala Instruments
Service policy
Full Calibration service capability in HEL, BOS, OK and BEI.
Additional three point temperature calibration is available for all models in HEL (MSL).
Customer selectable RH and points are available in HEL and BOS CRS
Accredited calibration is available for a new unit and the older ones too. Configuration of the
calibration is defined to order form of a new unit
Tools needed
- Power supply (V
Out
10...35V and I
Out
> 1A)
- Standard PC terminal software
- Vaisala USB service cable (order code 219690)
- Multimeters (DVMs)

Procedure Instruction 4(16)
Field Tech Manual for DMT143-series
2018-04-06
Vaisala Instruments
Wiring
Property Description/Value
Recommended calibration interval
to confirm the specified accuracy
2 years
Current Output Signal 4 … 20 mA.
Operating voltage
with current output
with voltage output
with RS-485
18 ... 28 VDC
12 ... 28 VDC
12 ... 28 VDC
Pressure > 20 bara (290 psia) or temp below 0 °C (32°F), 24 … 28 VDC
Supply current
during normal measurement
during self-diagnostics
Max 10 mA + load current
Max 220mA pulsed during purge
Load for current output Max 500 Ohms
Load for voltage output in 10k Ohms

Procedure Instruction 5(16)
Field Tech Manual for DMT143-series
2018-04-06
Vaisala Instruments
Trouble Shooting
4.1 Analog Output or Display does not match expected value
Step 1.) Check the label on transmitter, to verify the transmitter configuration of
parameters, engineering units and scale for appropriate channel.
Step 2.) With USB Service Cable, force analog outputs to 0% and 100% of scale to
verify reading on the control display, PLC, chart recorder, data logger or analog
receiving device displays correct scale.
Analog Output Tests
Using USB Service Cable and Service Port: ITEST Command
With the Pu Y serial program, use the A ES command to test the operation of the analog outputs. he
A ES command forces the analog outputs to entered values. he analog outputs remain at these values
until you enter the command A ES without parameters or reset the transmitter
Examples:
atest
17.585 24000
atest 4
4.000 5447
atest 20
20.000 27298
atest
17.583 27298
4.2 easurement Reading bounces around
If the measurement reading jumps around, this can be caused by several factors. Factors include unstable
process, varying control conditions, wrong location for sensor placement, ground loops, and leaks in
system allowing environmental conditions to affect process.
First, check the location of the installed sensor is not obstructed intermittently or insulated properly from
ambient fluctuations.

Procedure Instruction 6(16)
Field Tech Manual for DMT143-series
2018-04-06
Vaisala Instruments
Second, your process may fluctuate greatly. ry adjusting Filtering on control device in an effort to
stabilize readings. Or try adjusting FILT command with USB Service Cable for DM 143 output filtering
response
Set D T143 easurement Filtering
Use the FILT command to view or set the speed at which the latest measurement result is integrated into
the output readings. he command affects both analog output and serial line output.
FILT [a.aaa]<cr>
where
a.aaa = Range 0.001 ... 1.0.
1.0 = No filtering, latest measurement is output without averaging
0.5 = Average of last two measurements
0.1 = Average of ca. 16 measurements (default)
Example (show current setting):
filt
Filter : 0.100 ?
Example (set filtering to 0.5):
filt 0.5
Filter : 0.500
4.3 Checking Error essages with Service Port
If the transmitter has error messages, they can be read on the serial line using the ERRS command.
Example (one active error, caused by physical damage to the sensor):
errs
MEAS error

Procedure Instruction 7(16)
Field Tech Manual for DMT143-series
2018-04-06
Vaisala Instruments
Solving Typical Problems
Some problems can be solved by simply resetting power to the transmitter or issuing the RESE
command using the service port.
able 2. roubleshooting able
If resetting does not help, and if the problem is related to transmitter software or settings, you can
restore the factory configuration of the transmitter by issuing the FRESTORE command. If you are
unable to solve your problem with the transmitter, contact Vaisala technical support.

Procedure Instruction 8(16)
Field Tech Manual for DMT143-series
2018-04-06
Vaisala Instruments
4.4 Checking Error essages with Service Port
If the transmitter has error messages, they can be read on the serial line using the ERRS command.
Example (one active error, caused by physical damage to the sensor):
errs
MEAS error
4.5 Operational tests using USB Service Cable and Service Port
CAUTION! Before AC power up:
Connect always first the protective ground terminal. After that connect phase and null wires to POWER-1
module.
Connect USB serial line to Service port (fixed serial line settings, 19200, 8, N, 1) and multimeters (DVMs)
to analog outputs. Run Pu Y.
Power up the unit.
After power up the unit should response:
DM 143 1.3.4
ype command ? and hit enter
?
DM 143 1.3.4
Serial number : M3104715
Batch number : M18551904
Sensor number : L3820000
Sensor model : DRYCAP180D
Cal. date : 20160804

Procedure Instruction 9(16)
Field Tech Manual for DMT143-series
2018-04-06
Vaisala Instruments
Cal. info : Vaisala/HEL
ime : 02:20:19
Serial mode : S OP
SCI Baud P D S : 19000 N 8 1
Output interval : 1 s
Serial delay : 8
Address : 0
Pressure : 1.000 bar
Filter : 0.100
ype command R
he unit starts showing the readings. Pressing ESC <EN ER> stops displaying the readings.
Check the readings are reasonable and corresponds to the display (optional) and to the
analog outputs.
>r
RH= 37.33 % = 67.66'F
RH= 37.33 % = 67.66'F
RH= 37.34 % = 67.66'F
s
>
Example:
>asel
>
If the analog output readings are incorrect, those can be re-calibrated with command ACAL (see the
instructions from User´s Guide).
4.6 Changing Output Parameter and Channel information
If a transmitter channel information needs to be change from one parameter to another, use following
procedure.
Use the ASEL command to show or set the output parameter and the scaling of the analog output.
ASEL [parameter] [lowlimit highlimit]<cr>
where
parameter = Parameter that is output on analog channel.
Available parameters are TDF, TDFA, H2O. If the transmitter has been ordered from Vaisala
with a relative humidity output on the analog channel, also parameter RH is available.
lowlimit = Lower limit of parameter scaling.
highlimit = Higher limit of parameter scaling.

Procedure Instruction 10(16)
Field Tech Manual for DMT143-series
2018-04-06
Vaisala Instruments
Example (show current settings):
asel
Ch1 df lo : -80.00 'C ?
Ch1 df hi : 20.00 'C ?
Example (change output parameter to H2O, set low and high limits):
asel h2o 0 5000
Ch1 H2O lo : 0.00 ppm
Ch1 H2O hi : 5000.00 ppm
4.7 Reset to factory ordered configuration
o reset the transmitter settings to factory defaults, use command FRES ORE.
>frestore
Factory settings restored
4.8 Thread Types

Procedure Instruction 11(16)
Field Tech Manual for DMT143-series
2018-04-06
Vaisala Instruments
aintenance
5.1 Visual Check
his tasks should take into consideration at least following issues:
- Surface (materials)
- Oxidation, water leaking
- Sensors
- Cables (if any), cable heads
- Connectors
- Cleaning
5.2 Cleaning the HU ICAP sensor
he body of the transmitter can be cleaned by wiping with a moistened lint-free cloth. Do not immerse
the transmitter in liquid, and do not use cleaning agents or solvents.
When replacing the filter, wear clean gloves to avoid depositing dirt or oil on the filter. Inspect the
sealing ring for damage (used with ISO thread only), and replace it if necessary. Be careful when
changing the filter, since it is easy to break the sensor when the filter is removed.
Replace the filter as follows:
1. urn the filter counterclockwise until it is loose.
2. Pull the filter straight out carefully. Do not damage the sensor.
3. ake the new filter, and insert it to the filter thread.
4. ighten the new filter to 5 Nm by turning it clockwise.

Procedure Instruction 12(16)
Field Tech Manual for DMT143-series
2018-04-06
Vaisala Instruments
Spare or Replacement parts available for customers

Procedure Instruction 13(16)
Field Tech Manual for DMT143-series
2018-04-06
Vaisala Instruments
CALIBRATION AND ADJUSTMENT
Calibration and Adjustment Overview
You can calibrate and adjust the transmitter using the following tools:
•Serial line commands
•Portable humidity meter HM70
Vaisala Service Centers also offer accredited calibrations dewpoint.
Field Check Using the DM70 Hand-Held Dewpoint Meter
Vaisala recommends the following equipment for field checking:
- A fully charged MI70 indicator (the measurement display that is included in the DM70
package).
- A calibrated reference probe that is suitable for the intended measurement environment
and dewpoint range. he DMP74B probe is recommended for checking the dewpoint and
temperature measurement accuracy.
- You also need a connection cable (Vaisala order code: 219980SP) to connect the DM 143
to the MI70 indicator.
NOTE In the procedure below, the readings of the transmitter and the reference probe are checked
simultaneously. You can also check the reference probe and the DM 143 separately if they cannot be
connected at the same time.
Perform the check as follows:
1. Place the reference probe and the DM 143 in the reference environment.
2. Connect the reference probe and the DM 143 to the MI70 indicator:
- Reference probe to Port I
- DM 143 to Port II
3. If you have altered the DM 143 serial port settings, switch off the other power supply (disconnect
“Analog” cable if in use) before powering up the MI70. Note that this powers off the transmitter, and it
will carry out the startup sequence (see section DM 143 Startup Sequence on page 20) when powered
on again.
4. urn on the MI70 indicator. Never connect or disconnect the MI70 indicator while it is powered on, as
this may cause incorrect values to be displayed.
5. Check and adjust the environment settings if prompted. Refer to the DM70 User’s Guide for the
settings of the DMP74B probe.

Procedure Instruction 14(16)
Field Tech Manual for DMT143-series
2018-04-06
Vaisala Instruments
6. Disable the Auto power off function of the MI70 indicator to prevent the indicator from powering off
in the middle of the check.
Check the setting in the Settings - User Interface menu, and change if necessary.
7. he MI70 can display three parameters at one time. o compare the readings of the DM 143 and the
reference probe, select the desired parameter from the Display – Quantities and Units menu of the
MI70.
Select the same parameter from port I and II, and the delta parameter that shows the difference between
the two. For example, ΔTd/f shows the difference in dewpoint between the two probes.
Figure 24 Comparing Dewpoint Readings on I70
8. After the measurement has stabilized, check the difference between the readings. It will give you an
indication of the approximate drift of the DM 143 and its need for calibration. he difference between
the readings should be no greater than the combined measurement uncertainty of the DM 143 and the
reference probe.
9. Write down the results and repeat the comparison for each parameter you want to check.
10. If adjustment is required, contact a Vaisala Service Center or your local Vaisala representative to have
the DM 143 adjusted.
NOTE Some notes on using the MI70 indicator with the DM 143:
- If you disconnect the DM 143 while the MI70 indicator is on, the parameters measured
will remain on the screen, but no measurement will be shown.
- emperature measured by the DM 143 is shown as parameter Ta (not ) in the MI70.
- he messages from the transmitter will appear in English even if the MI70 has been set to
another language

Procedure Instruction 15(16)
Field Tech Manual for DMT143-series
2018-04-06
Vaisala Instruments
DMT143 Order Codes

Procedure Instruction 16(16)
Field Tech Manual for DMT143-series
2018-04-06
Vaisala Instruments
Calculate mA and rocess Values
To find the mA current value from Process Value:
I = (Ihigh - Ilow)/(PVhigh - PVlow) x (PV - PVlow) Ilow
For example:
Humidity Output: 4-20mA = -80 to 20 Td Deg C
PVhigh = 20
PVlow = -80
Ihigh = 20
Ilow = 4
PV on display = -40 Td deg C
I = (20 - 4)/( 20 – (-80)) x (-40 – (-80)) 4 = 10.40 mA
Using a calculator
I span = Ihigh-Ilow = 20 – 4 = 16 mA
PV span = PVhigh – PVlow = 20 – (-80) = 100 Deg C
Display Reading = -40 Td deg C
Calculate PV offset = -40 – (-80) = 40
I span / PV span = 16 / 100 = 0.16
Span x PV offset PVlow = 0.16 x 40 4 = 10.40 mA
To find the Process Value from mA:
PV = (PVhigh - PVlow)/(Ihigh - Ilow) x (I - Ilow) PVlow
For example:
Temperature Output: 4-20mA = 20 to -80 Td Deg c
PVhigh = 20
PVlow = -80
Ihigh = 20
Ilow = 4
mA Reading on Multimeter = 12.00mA
PV = (20 - (-80))/(20 - 4) x (12 - 4) (-80) = -30 deg C
Using a calculator
PV span = PVhigh – PVlow = 20 – (-80) = 100 deg C
I span = Ihigh-Ilow = 20 – 4 = 16 mA
Multimeter Reading = 12.00 mA
Calculate I offset = 12.00 – 4 = 8 mA
PV span / I span = 100 / 16 = 6.25
Span x I offset PVlow = 6.25 x 8 -80 = -30 deg C