HART® Compatible Intelligent 2

HART® Compatible Intelligent
2-wire DIN Rail Transmitters
MESO-L is a Smart and universal 2-wire DIN
Rail transmitter for temperature and other
measurement applications.
MESO-LX is the Intrinsic Safe version for use in
Ex-applications.
MESO-L and MESO-LX are fully HART-compatible, with communication through the HART
protocol, directly on the 4-20 mA output loop,
by using either a general hand-held HART Communicator or the Inor PC software, MEPRO 2.
MEPRO 2 is a Windows based and user friendly
software, which facilitates the access to and
use of functions like transmitter configuration, documentation, monitoring and calibration.
Performance and design:
Functions:
Excellent stability
Fully HART® Compatible
• Long-term stability 0.1 %/year.
• True on-line communication with hand-held HART
Communicator or Windows software MEPRO 2.
Enhanced total system accuracy
• Sensor error correction (compensates for known
sensor errors).
Input-Output isolation 1500 VAC
• Eliminates measuring errors due to ground loops.
High load capacity
• Only 11 V voltage drop over the transmitter
(MESO-L) allows for high loads.
Designed for harsh conditions
• Excellent EMC performance.
• Durable due to protected PCBs.
Space saving and simple mounting
• Only 17.5 mm/0.7 inch wide.
• Quick mounting on DIN rail.
5 year limited warranty
Input for RTDs, T/Cs, mV and resistance
• Reduced inventory costs.
• Simplified plant engineering.
Efficient customized 50-point linearization
• Any sensor characteristics can be matched.
Sensor diagnostics
• SmartSense detects low sensor isolation (essential
for correct measurements).
• Selectable sensor break action.
Simplified loop check-up
• The transmitter works as an accurate current
generator.
On-screen indications of input and output
• Valuable tools for temporary measurements.
Improved QA with data storage
• Vital information, such as TAG-No., maintenance
record etc. can be stored in the nonvolatile memory.
MESO-L/LX
Main features of MESO-L and MESO-LX
Accuracy and stability
Customized linearization and Engineering units
MESO-L/MESO-LX are designed for applications with
high demands on accuracy, also under severe operating
conditions. To reach these demands, the following factors
are essential:
Linearity and calibration errors - The combination of an
efficient linearization function and the use of quality components and precision calibration equipment reduce these
errors to ±0.1% of span.
Ambient temperature influence - The transmitters in the
MESO family are compensated to reduce the ambient
temperature influence to low levels.
High long-term stability - Internal “self calibration“, by
means of continuous adjustment of important parameters
after comparison with accurate built-in references, contributes to a stability of ±0.1%/year.
Measurements with RTDs and other resistances
MESO-L/ME110-LX accept inputs from standardized
Platinum and Nickel RTDs like Pt10…Pt1000 acc. to IEC
751 (α=0.00385), Pt100 acc. to JIS 1604 (α=0.003916) and
Ni100 / Ni1000 acc. to DIN 43760, as well as inputs from
plain resistance sensors such as potentiometers.
3- or 4-wire connection can be chosen.
The accurate and versatile 50-point Customized
linearization can be used to create almost any type of
linearization curve for RTD, T/C, resistance and mV inputs. By combining Customized linearization with the use
of Engineering units, the transmitters can be programmed
to give a linear output corresponding to a specific measuring range expressed in the primary process value.
The sensor characteristics are described by either up to
50 data pairs or a third order polynomial. Fig. 2a and 2b.
Fig.2a
Process
value
0-100 kPa
Sensor
output
0-50 mV
Sensor
Transmitter
Transmitter
output
4-20 mA
Fig.2b
mV
Sensor
mA
50
System
20
4
0
kPa
100
kPa
100
Measurements with thermocouples and plain voltage
MESO-L/MESO-LX accept inputs from 11 types of standardized thermocouples as well as plain mV input.
For T/C input, the CJC (Cold Junction Compensation) is
fully automatic, by means of an accurate measurement of
the terminal temperature. Alternatively, the CJC can be
disabled.
Sensor error correction
MESO-L/MESO-LX offer a way of improving the measurement with temperature sensors:
Known sensor errors compared to the standard curve, e.g.
for a calibrated sensor, are entered, and the transmitter
automatically corrects for the sensor errors. Fig. 1.
Fig.1 Sensor error correction
Sensor output
[Ω/mV]
∆Tmax
Tmin and Tmax= End values
of the measuring range.
Standard curve
Sensor curve
∆Tmin
Temp.
Tmin.
Tmax.
[°C/°F]
∆Tmin and ∆Tmax= Deviations
from Standard curve
at Tmin and Tmax.
The transmitter
compensates for the
deviations and transforms
the Sensor curve to a
Standard curve
SmartSense - Sensor isolation monitoring
SmartSense continuously monitors the isolation resistance
of thermocouples and 3-wire connected RTDs as well as
the cabling between sensor and transmitter. The transmitter will react by forcing the output to a user defined level
if the isolation level is too low. SmartSense requires an
extra lead inside the thermocouple or RTD. Fig. 6.
For detailed information, see section Theory and Facts.
Sensor break monitoring
MESO-L/MESO-LX monitor sensor break and force the
output signal to a user defined level, when any sensor lead
is broken or disconnected. The sensor break monitoring
can be switched off. The monitoring is furnished with a
pulsed excitation current. This eliminates the voltage drop in
the lead wires (giving a measuring error), caused by a
standard DC excitation current.
Controlled output for instrument calibration
With MEPRO 2, MESO-L/MESO-LX can be set to automatically provide the recurring output values of 4, 12, 20,
12, 4 mA in a periodical scheme. Each level will last 15 seconds. The total time for controlled output is adjustable up
to 30 minutes. With the hand-held Hart Communicator
model 275, a constant transmitter output can be set at any
level between 4 and 20 mA.
MESO-L/LX
Adjustable damping
The dampening function can be used to dampen undesired instabilities on the input signal. The dampening time
can be set to values between 0 and 10 seconds in intervals
of 1 second. The dampening time is measured as the time
required, in addition to the update time, for the output to
reach 90% of its final value after a step change has been
applied to the input.
Power supply
MESO-L/MESO-LX are loop-powered and will work on
voltages down to 11 VDC (12 VDC for MESO-HX).
Reversed polarity will not damage the transmitter.
Since the HART communication requires a loop resistance
of at least 250 Ω, the minimum power supply is 16.75 VDC
for MESO-L and 17.75 VDC for MESO-LX.
The relation between supply voltage and permissible load
in the output loop is shown in fig. 7.
Mounting
MESO-L/MESO-LX are designed to fit on a standard 35
mm rail according to DIN EN 50022.
Output cabling
MESO-L/MESO-LX allow for long output cables. The
length is determined by the combination of the cable capacitance, the cable resistance, and the load resistance. Fig. 3.
Fig.3
Maximum length
Meter Feet
1400 4600
1200 4000
1000 3200
800 2600
600 2000
100 pF/m
150 pF/m
200 pF/m
400 1300
200 650
0
0
400
600
800
1000
RLoad +RCable (Ω)
Warranty
MESO-L/MESO-LX are covered by a 5 year limited
warranty.
MESO-L/LX
The HART Concept
HART® is a master-slave concept where compatible instruments like MESO-L/MESO-LX are the slave devices.
The master can be either a PC with the INOR MEPRO 2
software and a HART modem, or the hand-held HART
Communicator, model 275.
The HART protocol uses the very robust FSK (Frequency
Shift Keying) communication method. The frequency signal
is superimposed on the 4-20 mA signal as a near sinusshaped waveform. The average value of the superimposed
signal is 0, and therefore, it will not interfere with the 4-20
mA signal.
For a more detailed explanation of the HART concept, the
reader is referred to “A Technical Overview“, published by
the HART Communication Foundation.
Standard mode
In the standard mode, the 4-20 mA output is active, and
the master is connected anywhere across the output leads.
Please note, that there must be a resistance of at least 250 Ω
between the connection point and the power supply for
safe HART communication. The total loop resistance (load
+ cable) should not exceed 1100 Ω. Fig. 5.
Communicating with PC and MEPRO 2 software
MEPRO 2, which is used with all MESO-transmitters, is
the best tool to utilize all the versatile functions of the
MESO-L/MESO-LX such as:
• Measurement configuration: sensor type, range, sensor
error correction, linearization, engineering units, output
settings, filter activation, etc.
• Monitoring of the sensor status:
Sensor break and sensor isolation (SmartSense).
• Transmitter diagnostics.
• On-screen real time presentation of measured values
and output signal.
• Transmitter basic calibration.
• Documentation: Configuration files can be saved for
future use and configuration protocols can easily be
printed.
MEPRO 2 is compatible with Windows 3.1, Windows 3.11
and Windows 95. The program is menu-driven and easy to
use. On-line help is an effective tool for the user.
Multidrop mode
Communicating with HART Communicator
In multidrop mode, the 4-20 mA output is not used (locked
to 4 mA). A maximum of 15 units in the same loop can communicate digitally with the master. Each unit will only reply to messages directed to its personal address. The message rate is 2-3 complete messages per second. Fig. 4.
In a system with different HART compatible units, the
HART Communicator, model 275, offers a great advantage.
When connected to the current loop, the device automatically recognizes the slave’s make and model and is directly ready to communicate. The HART Communicator
can reach all functions within the MESO-L/MESO-LX
(except for the Customized Linearization with data pairs
and transmitter calibration).
The software of the HART Communicator must include
the DD (Device Description) for MESO. New devices delivered as of July, 1997, normally include the DD for MESO,
and older communicators can easily be upgraded by the
supplier of the device.
Fig.4
+
RLOAD
Fig.5
Up to ~1500 m
4-20 mA
DCS, PLC etc.
HART
R ≥ 250 Ω
+
-
Field instruments
MESO-L
Modem
Alternatives
HART Communicator with DD for MESO
Typical ”Standard Mode” installation. Special requirements
for Hazardous Locations (see Conformity Certificates).
HART is registered trademark of HART Communication Foundation.
PC with MEPRO 2
MESO-L/LX
MESO-L/MESO-LX Configuration scheme
RTD
Input
Pt100
Pt1000
PtX
Ni100
Ni1000
D100
Linearity
Connections
and additional
functions
Thermocouple
(IEC751, α=0.00385)
(IEC751, α=0.00385)
10 ≤ X ≤ 1000 (IEC751,
α=0.00385)
(DIN 43760)
(DIN 43760)
(Pt 100 acc.
to JIS1604, α=0.003916)
Temperature linear
Resistance linear
3-wire connection
4-wire connection
3-wire connection
+ SmartSense (Pt100)
Diff temperature (Pt100)
Sensor break protection
Sensor error correction
Resistance
Voltage
Span:
10 Ω to 2000 Ω
Span:
2 mV to 500 mV
Temperature linear
Voltage linear
Customized linearization
Resistance linear
Customized
linearization
Voltage linear
Customized
linearization
Cold junction
compensation (CJC)
No CJC
CJC + SmartSense
Sensor break protection
Sensor error correction
3-wire connection
4-wire connection
Engineering unit
Sensor break protection
Min/max correction
type AE
W5%Rh-W26%Rh
type B
Pt30%Rh - Pt6%Rh
type E NiCr-CuNi
type J Fe-CuNi
type K NiCr-Ni
type L Fe-CuNi
type N NiCrSi-NiSi
type R Pt13%Rh-Pt
type S Pt10%Rh-Pt
type T Cu-CuNi
type U Cu-CuNi
Customer specific
Dampening
Dampening time 0-10 s
Output
4 -20 mA 20 - 4 mA
Special
Current
Engineering unit
Min/max correction
MESO-L/LX
Specifications
Input
RTD’s and Resistance
Pt100 (IEC751, α=0.00385)
Pt1000 (IEC751, α=0.00385)
PtX 10 ≤ X ≤ 1000 (IEC751, α=0.00385)
3-, 4-wire connection
-200 to +1000 °C / -328 to +1832 °F
3-, 4-wire connection
-200 to +200 °C / -328 to +392 °F
3-, 4-wire connection
Upper range depending on X-value
Ni100 (DIN 43760)
3-, 4-wire connection
-60 to+250 °C / -76 to +482 °F
Ni1000 (DIN 43760)
3-, 4-wire connection
-60 to +150 °C / -76 to +302 °F
D100 (Pt 100 acc.to JIS1604, α=0.003916) 3-, 4-wire connection
-200 to +1000 °C / -328 to +1832 °F
Potentiometer/resistance
0 to 2000 Ω
3-, 4-wire connection
Sensor current
~ 0.4 mA
Maximum sensor wire resistance
25 Ω/wire
Thermocouples and Voltage
T/C
Type: AE, B, E, J, K, L, N, R, S, T, U
Ranges according to users manual
Voltage input
-10 to +500 mV
Input impedance
>10 MΩ
Maximum sensor wire resistance
500 Ω (total loop)
Monitoring
Sensor break monitoring
User definable output
3.6 to 22.8 mA
SmartSense, sensor isolation monitoring
User definable output
3.6 to 22.8 mA
All inputs
Any value within range limits
Adjustments
Zero adjustment
Minimum spans
Pt100, Pt1000, Ni100, Ni1000
10 °C / 18 °F
Potentiometer
10 Ω
T/C, mV
2 mV
Output
Straight,reversed or any intermediate value
4-20/20-4 mA
Resolution
5 µA
Minimum output signal
~3.6 mA
Maximum output signal
~ 23 mA
Permissible load, see fig.7
MESO-L
565 Ω @ 24 VDC, 23 mA 1)
MESO-LX
520 Ω @ 24 VDC, 23 mA 1) 4)
MESO-L
-20 to +70 °C / -4 to +158 °F
MESO-LX
According to Ex-approval (pending)
Temperature
-20 to +70 °C / -4 to +158 °F
Ambient, storage
Ambient, operation
General data
Adjustable dampening time
0 to 10 s
Update time
~ 0.8 s 5)
Isolation In - Out
1500 VAC, 1 min
Humidity (non-condensing)
0 to 95 %RH
Intrinsic safety
MESO-LX, Cenelec
FM
Approval pending
Approval pending
Power supply, polarity protected
Supply voltage
MESO-L
11 to 42 VDC 2-wire 2)
MESO-LX
12 to 30 VDC 2-wire
Permissible ripple
1)
2)
3)
4)
5)
Higher load permitted with higher supply voltage (see fig. 7).
Minimum 250 Ω required for HART communication.
With 250 Ω in the output loop, a minimum of 16.75 VDC (MESO-L)
or 17.75 VDC (MESO-LX) is required.
For detailed information about permissible noise, we refer to
the HART specification HCF-SPEC-54.
Preliminary data
~1.5 s with Sensor Break Monitoring activated
2 V p-p @ 50/60Hz
3)
2) 4)
MESO-L/LX
Accuracy
Linearity
Calibration
RTD Potentiometer, mV
±0.1 % 1)
T/C
±0.1 %
RTD
Max. of ±0.2 °C / ±0.4 °F or ±0.1 % 1)
Potentiometer
Max. of ±0.1 Ω or ±0.1 % 1)
mV, T/C
Max. of ±20 µV or ±0.1 % 1)
1)
Cold Junction Compensation (CJC)
T/C
±0.5 °C / ±0.9 °F
Temperature influence 4)
All inputs
Max. of ±0.25 °C/25 °C or ±0.25 %/25 °C 1) 3)
Max. of ±0.5 °F/50 °F or ± 0.28 %/50 °F 1) 3)
Temperature influence CJC
4)
T/C
±0.5 °C/25 °C / ±1.0 °F/50 °F
Instrument calibration output
4-20 mA
±8 µA
Sensor wire resistance influence
RTD, Potentiometer, 3-wire
Negligible
RTD, Potentiometer, 4-wire
Negligible
mV, T/C
Negligible
2)
Load influence
Negligible
Power supply influence
Negligible
RFI influence, 0.15-1000 MHz, 10 V or V/m
±0.2 % 1) (typical)
Long-term stability
±0.1 % 1) /year
Housing
Material / Flammability (UL)
PC + Glass fibre/V0
Mounting
Rail acc. to DIN EN 50022, 35 mm
Connection
Single/stranded wires
≤1.5 mm2, AWG 16
Weight
70 g
Protection, housing / terminals
IP 20 / IP 20
1)
Of input span
With equal wire resistance
3)
If zero-deflection > 100% of input span:
add 0.125 % of input span/25 °C or 0.14 %
of input span/50 °F per 100 % zero-deflection
4)
Reference temperature 23 °C/73 °F
2)
The User Instructions must be read prior to adjustment and/or installation.
MESO-L/LX
INPUTS
RTD
Pt100, Pt1000, Ni100, Ni1000, PtX, D100
4-wire connection
3-wire connection
Pt100
Diff temperature T1>T2
Pt100
3-wire connection
T2
T1
*SmartSense lead
Potentiometer
4-wire connection
Thermocouple
Voltage
3-wire connection
millivolt
AE,B,E,J,K,L,N,R,S,T,U
or customer specific
- +
*SmartSense lead
- +
OUTPUT
Connections
4-20 mA Output
Power
Supply
Power +
Supply
-
R≥ 250 Ω
C
+ RLoad
B
17.5/0.69
Modem
+
Special
requirements
apply for
MESO-LX for
Hazardeus
Locations.
*Only for
58/2.28
B
Modem
*
-Test
(mA)
A
Dimensions
IOUT
78
56
7 - Test
5+ Out - 6
-
V/mA
+
1
2
3
4
A-B and B-C
are possible
connection
points for
HART Modem or
Communicator.
45/ 90/
1.77 3.54
35/
1.38
12
34
MESO-L
mm / inches
Input
Output load diagram
SmartSense
Fig.6
Ordering table
Fig.7
*
*
Permissible RLoad at 23 mA output
RLoad (Ω)
1500
1250
1000
750
500
250
MESO-LX
MESO-L
0
10 14 18 22 26 30 34 38 42
Supply voltage U (VDC)
Pt100
T/C
*SmartSense lead
Item
Transmitter
MESO-L
MESO-LX,(Cenelec)
MESO-LX,(FM)
Options
Configuration
Configuration with 5-point
calibration certificate
Software, Modem
Software MEPRO
HART Modem RS 232
Part No.
70MEL00001
Consult Inor
Consult Inor
70CAL00001
70CAL00051
70MEP00001
70MEM00001
RLoad=(U-11)/0.023 (MESO-L)
RLoad=(U-12)/0.023 (MESO-LX)
INOR MESO-L, MESO-LX
Distributor - ThermX Southwest 7370 Opportunity Road, Suite S, San Diego, CA 92111-1414 (800) 284-3769 www.thermx.com
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