Vaisala HMP260 User Manual
HMP260 SERIES
TRANSMITTERS
Operating Manual
HMP260-U017en-1.5
5 January 1996
Vaisala 1996
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Back of cover page.
HMP260 SERIES
HMP260-U017en-1.5 Operating Manual
Contents
1. PRODUCT DESCRIPTION ......................................................................................... 1
2. TO BE NOTED WHEN M EASURING HUMIDITY........................................................ 3
3. INSTALLATION.......................................................................................................... 4
3.1. Selecting the place of installation ................................................................ 4
3.2. Mounting........................................................................................................ 5
3.2.1. HMP263 transmitter ......................................................................... 6
3.2.2. HMP264 transmitter ......................................................................... 7
3.2.3. HMP265 transmitter ....................................................................... 10
3.3. Grounding .................................................................................................... 11
3.4. Electrical connections................................................................................. 13
4. COMMISSIONING .................................................................................................... 15
4.1. Security lock jumper ................................................................................... 15
4.2. Selecting the analogue outputs .................................................................. 15
4.3. Connecting the RS 232C serial bus............................................................ 17
4.3.1. Reverting to factory settings of the serial port................................. 19
5. COMMANDS ............................................................................................................ 21
5.1. Commands and security lock jumper ......................................................... 21
5.2. LED commands ........................................................................................... 22
5.3. Display/keypad commands......................................................................... 23
5.3.1. Display mode ................................................................................. 23
5.3.2. Command m ode............................................................................. 23
5.3.3. Entering numbers........................................................................... 23
5.3.4. Analogue output commands ........................................................... 24
5.3.4.1. Selecting the output (mA/V)........................................................ 24
5.3.4.2. Selecting and scaling the analogue output quantities.................. 25
5.3.5. Output via the serial bus ................................................................. 26
5.3.5.1. Turning the serial interface echo ON/OFF................................... 26
5.3.5.2. Serial bus settings...................................................................... 26
5.3.5.3. Setting the transmitter address................................................... 27
5.3.5.4. Selecting the output units ........................................................... 27
5.3.6. Output modes................................................................................. 28
5.3.6.1. Setting the serial interface operation mode................................. 28
5.3.7. Others .......................................................................................... 29
5.3.7.1. Setting the measurement integration tim e................................... 29
5.3.7.2. Setting the pressure for m ixing ratio and wet bulb calc ulations ... 29
5.3.7.3. Setting the date .......................................................................... 30
5.3.7.4. Setting the time .......................................................................... 30
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5.4. Serial commands ......................................................................................... 32
5.4.1. Analogue output commands ............................................................ 32
5.4.1.1. Setting the analogue outputs ....................................................... 32
5.4.1.2. Selecting and scaling the analogue output quantities ..................33
5.4.1.3. Scaling the analogue outputs ......................................................33
5.4.2. Output via the serial bus .................................................................34
5.4.2.1. Starting the measurement output ................................................34
5.4.2.2. Stopping the measurement output ............................................... 34
5.4.2.3. Outputting the reading once........................................................ 34
5.4.2.4. Setting the output interval for the RUN mode ..............................35
5.4.2.5. Serial bus settings.......................................................................35
5.4.2.6. Selecting the output units............................................................36
5.4.2.7. Setting the transmitter address ...................................................36
5.4.2.8. Resetting the transmitter.............................................................36
5.4.4. Operating the transmitter via the serial bus.....................................36
5.4.4.1. Setting the serial interface...........................................................36
5.4.4.2. OPEN & CLOSE .........................................................................37
6. CALIBRATION..........................................................................................................38
6.1. Humidity calibration ....................................................................................38
6.1.1. One point humidity calibration.........................................................39
6.1.1.1 Using serial commands...............................................................39
6.1.1.2 Using display/keypad commands ................................................39
6.1.1.3 Using LED commands................................................................. 40
6.1.2. Two point humidity calibration.........................................................40
6.1.2.1 Using serial commands...............................................................40
6.1.2.2 Using display/keypad commands ................................................41
6.1.2.3 Using LED commands................................................................. 41
6.1.3. Calibration procedure after sensor c hange ...................................... 42
6.1.3.1 Using serial commands...............................................................42
6.1.3.2 Using display/keypad commands ................................................43
6.1.3.3 Using LED commands................................................................. 43
6.1.4. Humidity calibration table................................................................44
6.2. Temperature calibration .............................................................................. 44
6.2.1 One point offs et correction..............................................................45
6.2.2.1 Using serial commands...............................................................45
6.2.2.2 Using display/keypad commands ................................................45
6.2.2.3 Using LED commands................................................................. 46
6.2.2 Two point temperature c alibration...................................................46
6.2.2.1 Using serial commands...............................................................46
6.2.2.2 Using display/keypad commands ................................................47
6.2.2.3 Using LED commands................................................................. 47
6.3. Calibration of analogue outputs .................................................................48
6.3.1 Using serial com m ands ................................................................... 48
6.3.2 Using display/keypad commands ....................................................48
6.3.3 Using LED com m ands ....................................................................50
7. MAINTENANCE........................................................................................................50
7.1. Reference measurements............................................................................50
7.2. Self-diagnostics...........................................................................................50
7.3. Changing the HUMICAP® sensor and the filter.......................................... 51
7.4. Measurement of output currents using test points.................................... 51
7.5. Adjusting the contrast of the display..........................................................52
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8. TECHNICAL DATA................................................................................................... 53
8.1. Relative humidity......................................................................................... 53
8.2. Temperature................................................................................................. 53
8.3. Calculated variables.................................................................................... 53
8.4. Pressure ....................................................................................................... 55
8.5. Analogue outputs........................................................................................ 55
8.6. Electronics ................................................................................................... 55
8.7. Mechanics.................................................................................................... 56
8.8. Environmental conditions ........................................................................... 58
8.8.1 Emissions ....................................................................................... 58
8.8.2 Imm unity ........................................................................................ 58
9. OPTIONS ................................................................................................................. 59
10. SPARE PARTS......................................................................................................... 59
Appendix 1 Serial commands
Appendix 2 Safety summary
Appendix 3 Installing and using the RS 485/422 serial port module
Appendix 4 Installing and using the digital current loop module
Appendix 5 Error messages
Appendix 6 Calculation formulas: dewpoint, m ixing ratio and abs olute hum idity
Appendix 7 Wiring diagr am MK4462
Appendix 8 Installation diagram MK4461
Appendix 9 Approvals and specifications of the protection unit
Certificates: Technical Research Centre of Finland No. Ex-94.C.016X
No. Ex-94.C.018X
DEMKO No. 94C.115330X
This manual is f or progr am m e vers ion HMPS260 1.01
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1. PRODUCT DESCRIPTION
NOTE
Before installing and using the HMP260 transmitter
study carefully Appendix 2: SAFETY SUMMARY.
The HMP260 series transmitters are associated electrical apparatuses. This
means that the housing of the transmitter is mounted into a safe area and the
sensor head and its cable can go to a potentially explosive environment
(hazardous area). The transmitters incorporate a protective unit which contains
the power limiting components. This unit prevents the entry of any hazardous
energies to the potentially explosive area.
The transmitters are microprocessor based instruments which measure relative
humidity and temperature; from these variables they can calculate dewpoint
temperature, absolute humidity, mixing ratio and wet bulb temperature. The
transmitters have two analogue outputs and can be connected to a serial bus
via the RS 232C interface or through an RS 485/422 serial module or a digital
current loop module.
The series consists of three types of transmitter:
• HMP263, installation in tight places; temperatures up to +120 °C
• HMP264, installation in pressure or vacuum chambers
• HMP265, installation in high temperatures up to +180 °C
There are various possibilities for the configuration of the transmitters. They
can have either a blank cover or a cover with a local display and keypad with
which to operate the transmitter. Two analogue output signals are selected
from the measured and calculated quantities; the signals can be scaled and the
measurement ranges changed within certain limits. The HMP263, HMP264
and HMP265 can be supplied with two, five, ten or 15 metre probe cable.
The humidity measuring range is 0...100 %RH. The temperature is measured
with a Pt 100 sensor. Temperature measurement range depends on the model;
the HMP264 and HMP265 have the widest range, -40...+180 °C. The analogue
temperature output can be scaled quite freely, for example -20...+60 °C can be
set to correspond to 0...10 V. The dewpoint temperature, absolute humidity,
mixing ratio and wet bulb temperature ranges are also scalable.
The HMP260 series units incorporate the HUMICAP® sensor, which uses an
operating principle based on changes in the capacitance of the sensor as its
thin polymer film absorbs water molecules.
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Operating Manual HMP260-U017en-1.5
Options
Calculation variables dewpoint temperature, mixing ratio, absolute hu-
midity, wet bulb temperature
Serial interface RS 232C (standard), RS 485/422, digital current
loop
Display cover cover with or without local display & keypad
Filters sintered filter, PPS grid with steel netting, PPS
grid
Cable length 2, 5,10 or 15 metres
Installation aids HMP263: installation kit
HMP264: NPT conical pipe threaded fitting body
(1/2 - 14 NPT)
HMP265: steel and aluminium flanges
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2. TO BE NOTED WHEN MEASURING HUMIDITY
In the measurement of humidity and especially in calibration, it is essential
that temperature equilibrium is reached. Even a small difference in
temperature between the measured object and the sensor causes an error. If the
temperature is +20 °C (+68 °F) and the relative humidity 50 %RH, a
difference of ±1 °C between the measured object and the sensor causes an
error of ±3 %RH. When the humidity is 90 %RH, the corresponding error is
±6 %RH.
The error is at its greatest when the sensor is colder or warmer than the surroundings and the humidity is high. A temperature difference of a few degrees
can cause water to condense on the sensor surface. In an unventilated space
evaporation may take hours; good ventilation accelerates evaporation. The
HUMICAP sensor starts to function normally as soon as the water has evaporated. If the condensed water is contaminated, the life span of the sensor may
shorten and calibration may change.
10
9
8
7
6
5
4
dRH (%RH)
3
2
1
0
-40-200 20406080100
Temperature (°C)
Fig. 2.1 Measurement error at 100 %RH when the difference between the
ambient and sensor temperature is 1 °C
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Operating Manual HMP260-U017en-1.5
3. INSTALLATION
3.1. Selecting the place of installation
The transmitters should be installed in a place that gives a true picture of the
environment or process and is as clean as possible. Air should circulate freely
around the sensor. A rapid air flow is recommended; it ensures that the sensor
head and the ambient air are at the same temperat ure.
Install the transmitter in a place where no cold or hot spot can develop. When
the sensor head is installed in a duct or a process channel where the
temperature is different from the ambient temperature, insulate the point of
entry; this is particularly important if the transmitter is installed with the
sensor head pointing downwards. Installing the sensor head vertically is not
recommended. An uninsulated installation could lead to condensation in the
sensor head and even when no condensation occurs, the resultant air flow may
change the temperature near the sensor and distort the readings.
Install the sensor head in the process wherever possible; avoid sample flows
where the gas temperature can drop below dewpoint temperature. Install the
sensor head transversely against the direction of the process flow.
In duct or channel installations drill a hole ready for a reference meter. Plug
the reference hole tightly.
The transmitters are associated electrical apparatuses: the electronics housing
must be in the safe area and only the sensor head and its cable may go into the
hazardous area.
Install the electronics housing away from possible steams escaping from the
process.
NOTE
To ensure an IP 65 class protection:
1. Always mount the transmitter housing with the cable
bushings pointing downwards.
2. Make sure that the connection cable has the right
thickness (∅ 7...10 mm) and that the cable bushing
is carefully tightened.
3. Pay always special attention to closing the
transmitter cover carefully and remember to tighten
all four screws.
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3.2. Mounting
HMP263/264/265
(EEx ia) IIC
Supply voltage 24 VDC
Analog outputs (mA/V)
RS 232C/ RS 485 /digital current loop
SAFE AREA
HAZARDOUS AREA
EEx ia IIC T3/T4
HMP263 sensor head
HMP264 sensor head
for pressurized spaces
HMP265 sensor head
.
Fig. 3.1 Examples of sensor head mounting
The lead-throughs must be sealed properly to avoid air flowing in or out from
the channel. The sealings must fulfil EEx requirements. When using the
support bar with the HMP263, the lead-through piece must be sealed e.g. with
silicon. See also Appendix 8.
133
104
Ø 6.5
Fig. 3.1 Mounting holes in the HMP260 transmitter housings
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The transmitters should be mounted with the sensor head horizontally; this
way, any water condensing on the tube cannot flow onto the sensors. When
there is no alternative but to install the sensor head in the process vertically,
the point of entry must be carefully insulated. The cable must also be allowed
to hang loosely as in Figure 3.6; this prevents any condensed water from
running onto the sensor head along the cable.
If the process temperature is much higher than that of the environment, the
whole sensor head and preferably part of the cable must be inside the process.
When mounted on the side of a duct or channel, the sensor head must be inserted from the side (see Figure 3.7). If this is not possible and the sensor head
must be inserted from the top, the point of entry must be carefully insulated.
NOTE
During installation the protective cover of the
protective unit must not be opened and the sensor head
must not be unsoldered from and then resoldered to the
protective unit of the transmitter. This procedure is not
allowed for the user. Vaisala is not responsible for any
damages caused by incorrect use.
3.2.1. HMP263 transmitter
The HMP263 can be installed in ducts and channels with the help of the installation kit available; the kit consists of a flange, a supporting bar for the
sensor head cable and screws for attaching the flange to the wall of a duct.
With the help of the installation kit the distance between the sensor head and
the channel wall can be easily adjusted. The range of adjustment is 100...320
mm; the distance is measured from the tip of the sensor head to the flange.
duct wall
a plugged hole for reference
measurements
flange
sealing
supporting bar
HAZARDOUS
AREA
SAFE AREA
Fig. 3.2 Installing the sensor head of the HMP263 in a channel with the
help of flange and supporting bar
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HMP260 SERIES
when a bushing is used, its size is
selected according to the diameter
of the sensor head; the diameter
of the cable increased by using
e.g. tape at the bushing
to be sealed
(loop type)
clamp
mounting the
sensor head
on a support
HAZARDOUS
AREA
SAFE AREA
HMP260-U017en-1.5 Operating Manual
NOTE
When using the support bar the lead-through piece and
the space between the duct wall and the flange must be
sealed e.g. with silicon. The sealings must fulfil EEx
requirements.
The sensor head can also be installed vertically.
Fig. 3.3 Vertical installation of the HMP263 sensor head
3.2.2. HMP264 transmitter
The HMP264 is supplied with a nut, a fitting body and a sealing washer.
During handling the fitting body and the nut should remain in place on the
body of the sensor head to prevent damage to the highly polished surface.
To achieve a leak-tight assembly:
1. Remove the fitting body from the nut and the sensor head.
2. Fasten the fitting body to the chamber wall. Tighten the fitting body
into the threaded sleeve with a torque spanner. The tightening torque
is 150 ±10 Nm.
HAZARDOUS AREA
sealing washer
fitting body
nut
tightening cone
SAFE AREA
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Operating Manual HMP260-U017en-1.5
3. Insert the body of the sensor head into the fitting body and screw the
nut manually to the fitting body until the connection feels tight.
4. Mark both the fitting body and the nut hex.
A pen
nut
fitting body
5. Tighten the nut a further 30° (1/12 turn) or if you have a torque spanner tighten it with a torque of 80 ±10 Nm.
NOTE
After detachment the nut must be tightened without
increased effort.
30°
6. The tightening cone of the fitting body has to be cleaned and greased
after each tenth detachment. Use high-vacuum grease (Down Corning,
Europe) or a similar grease.
clean cotton stick
tightening cone
sealing
washer
fitting body
The sealing washer has to be changed every time the fitting body is
detached.
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Fasten by threaded sleeve
Sealing by Metal sealing washer DIN 7603
M22x1.5
threaded sleeve M22x1.5/Ø40 x15
sheet metal
Fasten by Nut DIN 80705
Check the thickness of the sheet metal
according to the pressure of the chamber
nut DIN 80705-M22x1.5 (AISI 316)
tightening torque=150 Nm ±10 Nm
NPT Conical pipe threaded connection
ANSI/ASME B1.20.1-1983
sealing by anaerobic pipe thread seal
(SWAK, Cajon Company) or PTFE
(teflon) tape
1/2-14 NPT
(boring)
Ø22+0.3
s=3...6mm
sealing by Metal sealing washer
DIN 7603
fitting body. VAISALA code 17225
(AISI 316Ti). Body hex = 27 mm
tightening torque=150 Nm ±10 Nm
Fig. 3.4 Some examples on the installation of the HMP264 sensor head
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3.2.3. HMP265 transmitter
SAFE AREA
to be sealed
to be insulated
HAZARDOUS AREA
Fig. 3.5 Installing a transmitter in a process with the sensor head hori-
zontally
SAFE AREA
to be sealed
to be insulated
HAZARDOUS AREA
Fig. 3.6 Installing a transmitter in a process with the sensor head down-
wards (not recommended)
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HMP260-U017en-1.5 Operating Manual
a plugged hole
HAZARDOUS AREA
for an Exi-approve d
reference meter
SAFE AREA
Fig. 3.7 Mounting the sensor head on a duct or channel
When the sensor head is installed in a duct or a channel, the temperature
difference of the air inside and outside the duct must be small as the sensor
head conducts heat.
3.3. Grounding
A single electrical cable with a screen and three to ten wires is recommended
for power and analogue output/serial bus connections. The cable diameter
should be 7...10 mm.
The screen of the electrical cable must be grounded properly to achieve best
possible EMC performance. Recommended cable shield is done in the cable
gland as shown below.
• remove the brass disks, rubber ring and nut from the transmitter
housing
• strip 165 mm of the cable insulation, but leave 25 mm of the braid
visible
• slip the nut and rubber ring over the cable insulation
• slip the brass disk that has the bigger hole in it over the braid so that
it rests against the cable insulation
• slip the other brass disk over the wires to the middle of the braid
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braid
rubber
ring
165
brass
disks
nut
cable
140
25
3
flexible wires 0.5 mm
(AWG 20), stranded wires
recommended
D = Ø 7...10
(If the cable diameter is less
than 7mm, use a shrinking
tube or an adhesive tape)
2
shielding tube
braid
brass disks
• push back the braid and press it between the two brass disks to
achieve a full 360° grounding; the fold between the disks should have
the same diameter as the brass disks
• secure the braid with a shielding tube
• insert the wires into the transmitter housing through the gland.
• tighten the nut
• connect the wires into the screw terminals and fasten a cable tie
around the wires
cable tie
transmitter housing
gland
brass disks
rubber ring
nut
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NOTE
When the cable is grounded as above, the metallic parts
of the sensor head, the shield of its cable, the
transmitter housing and the shield of the signal cable to
external system are all connected to each other. The
transmitter housing must be grounded via the
grounding terminal located at the lower right hand
corner of the housing. In addition to this the
negative terminal of the power supply must be
grounded. If these groundings have not been made
correctly, the transmitter does not work.
HMP26x
Hazardous
area
Power
supply
The electrical safety of the grounding must comply with the EN 50014/13
standard. When compliance with Factory Mutual Standards is required, the
grounding must comply with ANSI/ISA RP 12.6 and ANSI/NFPA 70.
Always use the grounding terminal to connect the
transmitter to safety ground.
3.4. Electrical connections
All the component boards are grounded via the housing
frame. Make sure that the fixing screws of the boards
are firmly tightened before connecting the cables.
WARNING
CAUTION
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P
Operating Manual HMP260-U017en-1.5
CH1- and CH2- are connected
CH1+
CH1-
CH2+
together internally
CH2-
X2
X1
+-
V
mA
+-
V
mA
24 V +
CURRENT/VOLTAGE
OUTPUTS
EXTERNAL
POWER SUP
Do not use power supply
ground (-) as output signal
ground
OPENED COVER OF THE HMP260
Fig. 3.8 Electrical connections
Power supply 24 VDC
Output signals 0...20 mA
4...20 mA
0...1 V
0...5 V
0...10 V
IF THE CONNECTION INSTRUCTIONS ARE NOT
CAREFULLY FOLLOWED OR THE COMPONENTS
IN THE PROTECTION UNIT ARE MODIFIED OR
TAMPERED WITH, THE DEVICE DOES NOT MEET
THE REQUIREMENTS OF EXi CLASSIFICATION.
VAISALA IS NOT RESPONSIBLE FOR ANY DAMAGES CAUSED BY INCORRECT USE.
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4. COMMISSIONING
When the HMP260 transmitters leave the factory, their measurement ranges
and output signals have already been selected. The user can subsequently
change the measurement units between metric and non-metric and select and
scale the output signals with software functions, see Chapter 5 Commands and
Appendix 1.
4.1. Security lock jumper
Before the settings can be changed, the security lock jumper in connector X15
must be removed (see Fig. 4.1). The security lock jumper makes it impossible
to change the transmitter settings by mistake.
CHANGE OF SETTINGS
DISABLED
Fig. 4.1 Location of the security lock jumper
When the security lock jumper is connected, some commands are not avail able
(see Chapter 5 Commands).
Should the application require variables that are not included in the
configuration of the transmitter, the user is invited to contact Vaisala or a
Vaisala representative.
4.2 Selecting the analogue outputs
The HMP260 transmitters can be ordered ready with the current or voltage
outputs required. If the outputs need to be changed, move the jumpers in connector X15 into positions as shown in the Figure 4.2.
X15
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CH1
CH1
CH1
CH1
CH1
CH2
CH1
CH2
CH1
CH2
CH1
CH2
CH2
CURRENT OUTPUTS
0 ... 20 / 4 ... 20 mA
CH2
VOLTAGE OUTPUTS
0 ... 5 V / 0 ... 10 V
CH2
VOLTAGE OUTPUTS
0 ... 1 V
CH2
CH1 0 ... 1 VOLTAGE OUTPUT
CH2 CURRENT OUTPUT
X15
OPENED COVER OF THE HMP260
Fig. 4.2 Selecting the analogue outputs with jumpers
The software has to be informed which outputs are in use. This is done either
through the serial interface or the menus on local display when one is in use.
The serial command is AMODE and the display/keypad command "Mode
Analog outputs Mode" (see Chapter 5 Commands). If the outputs need to
be scaled, see serial command ASCL and the display command "Mode
Analog outputs Scale".
All the jumpers are used only with the 0...1 V outputs. When other outputs are
in use, the spare jumpers are kept in connector X55.
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X55
spare jumpers
Fig. 4.3 Spare j umpers
4.3 Connecting the RS 232C serial bus
RX
GND
TX
NC
X6
Fig. 4.4 Serial bus connections
To connect a PC to the HMP260 transmitters via the RS 232C serial bus, one
of the following cables is required. The type of cable depends on the terminal
and the connector type.
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HMP260 SERIES
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Operating Manual HMP260-U017en-1.5
RXD
RXD
RXD
TXD
TXD
TXD
TX
GND
RX
TX
GND
RX
TX
GND
RX
HMP 2
PC
TERMINAL
D9S
D25S
D25P
2
5
3
4
6
7
8
3
7
2
5
6
8
20
3
7
2
Fig. 4.5 Connection of cables
When the serial bus has been connected between the PC and the transmitter,
the PC is switched on. When using a PC, a terminal emulation programme
(e.g. Procomm Plus, Datastorm or Windows terminal) is started.
The factory settings for data transfer are:
• 4800 baud
• even parity
• 7 data bits
• 1 stop bit
• full duplex
NOTE
When the serial bus settings are changed, the transmitter has to be reset before the new settings become effective.
The processor does not allow the following combinations:
• no parity, 7 data bits, 1 stop bit: if this combination is given the
HMP260 programme will change the number of stop bits to 2
• even or odd parity, 8 data bits, 2 stop bits: if this combination is given
the programme changes the number of stop bits to 1
Refer to the manuals of the PC and the terminal emulation programme when
giving serial settings.
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HMP260-U017en-1.5 Operating Manual
The RS 232C screw terminal cannot be used if an RS 485/422 serial module
or a digital current loop module is used. See appendices 3 and 4 on how to
install and operate these modules.
In calibrating or changing the settings of the transmitter it can be more convenient to use the connector X17, if connector X6 is already in use. This connector, however, transfers only RS 232 signals. If an RS 485/422 serial port
module or a digital current loop module has been installed, it has to be
removed before communicating through the X17 connector.
RX GND T
X17
Fig. 4.6 Location and connections of connector X17
4.3.1 Reverting to factory settings of the serial port
If the serial port settings are not known, no commands can be given via the
serial interface. The settings can be reverted to the factory settings by inserting
a jumper in connector X16. The jumper must be i nserted wh en the pow er is
on!
cover of the protection unit
X16
Fig. 4.7 Forcing the serial port settings back to factory settings
When the jumper is inserted the serial line factory settings become valid, but
only temporarily. The transmitter must be given new settings; otherwise
the transmitter uses the old, unknown settings after power-up. When the
new settings have been given, the transmitter must be reset. Note that the
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jumper must be removed before the transmitter is reset. If the jumper is in
place when power i s turned on, the tran smitter does not w ork.
After jumper insertion the transmitter is in STOP mode, ready to receive
commands.
The same method is used when the transmitter is in POLL mode and the user
has forgotten its address.
NOTE
Inserting a jumper in any other place in connector X16
voids the guarantee of the transmitter.
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5. COMMANDS
As the HMP260 transmitters are microprocessor based devices, their
configuration can be set to correspond to the specific needs of the user. This is
done through commands, either utilizing the menus on the local display or by
giving commands through the serial interface (see Appendix 1). Most often
the commands are used to change the settings of the two analogue channels.
A limited range of commands can be given by using the three press switches up, down and enter - inside the transmitter housing. Four LEDs indicate the
command given with the up and down switches. The switches and LEDs are in
all HMP260 transmitters. LED commands can be used to calibrate the transmitters (both humidity and temperature) or to calibrate the analogue outputs.
A full range of commands can be given through the display/keypad or through
the RS 232C serial bus. The commands can be used e.g. to select and scale the
outputs, to calibrate the humidity and temperature channels as well as the
analogue outputs and to set the serial interface.
5.1 Commands and security lock jumper
In order to prevent any tampering with the transmitter settings, the transmitters
can not be calibrated, the analogue outputs set or the analogue output quantities selected or scaled unless the security lock jumper has been disconnected.
The commands involved are:
• all LED commands
• display/keypad commands:
Cali RH cal T cal
Analog outputs
Mode Analog outputs Mode
• serial commands:
CRH, CT, FCRH, ACAL; AMODE, ASEL, ASCL
In the following, the description of these functions is preceded with a reminder of the security lock jumper:
Disconnect the security lock jumper!
Scale
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5.2 LED commands
NOTE
If the transmitter has a display/keypad cover, the LED
commands cannot be used.
LED commands can be used to operate the transmitters in the field. These
commands can be used in humidity and temperature calibration and calibration
of the analogue outputs.
Open the housing and press any one of the three press switches. The LEDs
will light up for 2...3 seconds.
UP
DOWN
ENT
press switches
LEDs
Fig. 5.1 Location of press switches and LEDs
Use the up and down switches (marked with arrows on the printed board) to
find the desired command code and acknowledge it with the ENT switch. The
command codes are (l = lit, ¡ = dark):
¡¡¡¡ (0) return to normal state
¡¡¡l (1) relative humidity calibration
¡¡l¡ (2) tem perature cali bration
¡¡ll (3) calibration of analogue outputs
l¡¡¡ (8) relative humidity calibration after sensor change
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5.3 Display/keypad commands
5.3.1 Display mode
In the display mode the transmitters output measurements on the display; different quantities can be scrolled with the arrow keys according to the variables
selected when ordering the transmitter. After reset the transmitters are always
in the display mode.
The display also shows error messages and alarms if they occur.
5.3.2 Command mode
Press the CL key to enter the command mode. The first display is the main
menu:
The commands can be scrolled with the arrow keys. The currently active
commands flashes; a command is selected with the ENT key. When a menu is
displayed, either the first command or the currently valid setting flashes. The
CL key takes the transmitter back to the display mode.
5.3.3 Entering numbers
When the transmitter needs numbers to be entered into the programme (e.g.
when scaling or setting the analogue outputs, in calibration or when giving the
transmitter an address), the field is either empty or the currently valid figure is
displayed. Any previously given value is deleted with the CL key.
When the field is empty, a cursor blinks at the right side of the display.
Pressing the arrow keys brings either a blank ' ', a comma ',', a dash '-', a full
stop '.' or a number from '0' to '9' on the display. The right character is selected
with ENT; after that the number or numbers move left one step. Entering
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numbers is ended with selecting a blank ' ' and pressing ENT. The last character entered can be deleted with CL. If CL or ENT key is pressed when the field
is empty, the programme returns to the previous display.
With some commands (e.g. calibration) the figures are changed using the arrow keys. When an arrow key is pressed continuously for a while, the numbers
start changing at an increasing rate.
5.3.4 Analogue output commands
5.3.4.1 Selecting the output (mA/V)
Disconnect the security lock jumper!
• Select Mode in the main menu and Analog outputs in the Mode
menu:
• Select Mode ( mA / V ). The current settings for channel 1 are dis-
played:
• If the settings are correct, press ENT.
• If the settings need to be changed, press CL:
− the quantity (mA/V) starts flashing; it can be changed with the ar-
row keys and acknowledged with the ENT key
− the lower limit starts flashing
− acknowledge the lower limit with ENT or start changing it by
pressing CL; a new lower limit is given one character at a time
with the arrow keys
− the upper limit starts flashing
− acknowledge the upper limit with ENT or start changing it by
pressing CL; a new upper limit is given one character at a time
with the arrow keys
When channel 1 has been set, the programme goes on to channel 2;
the procedure is the same as with channel 1.
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