Priced at only $235
(basic temperature transmitter)
Options:
Low voltage power,
10-48 Vdc or 12-32 Vac
Description
The Laureate Modbus and
serial output RTD
temperature transmitter provides
a linearized, highly accurate, stable
and repeatable transmitter output for 100 ohm platinum,
10 ohm copper and 120 ohm nickel RTDs. Pt 100 platinum RTDs can have a
DIN alpha of 0.00385 or ANSI alpha of 0.00392. The RTD type and temperature
range, specified in °C or °F, are user-selectable.
Digital
calibration of all
RTD ranges is performed the factory, with calibration data stored
in EEPROM on the signal conditioner board. This allows signal
conditioner boards and ranges to be changed in the field with no need for
recalibration. Open sensor indication is standard and may be set up to indicate either upscale or
downscale. RTD excitation is provided by the transmitter. RTD connections can be of the 2-, 3-
or 4-wire type. With 3- and 4-wire connections, the transmitter automatically compensates for
lead resistance of the sensor.
Fast read rate at up to 50
or 60 conversions per second while integrating the signal over a
full power line cycle is provided by Concurrent Slope (Pat 5,262,780)
analog-to-digital conversion. High read
rate is ideal for peak or valley capture and for real-time computer interface and control.
LTM Series serial
output transmitters send data via an isolated serial port, which is user
configurable for RS232 or RS485 and full or half duplex operation. Three
protocols are user selectable: Modbus RTU, Modbus ASCII, or Laurel ASCII. Modbus operation
is fully compliant with Modbus Over Serial Line Specification V1.0 (2002).
The Laurel ASCII
protocol allows up to 31 Laureate devices to be addressed on the
same RS485 data line. It is simpler than the Modbus protocol and is
recommended when all devices are Laureates. It also allows use of
Laurel Datalogging Software.
Standard features of Laureate
temperature transmitters include:
Serial data output, isolated. User selectable RS232 or RS485, half or full duplex, Modbus or
Laurel ASCII protocol.
Dual solid state relays for control or alarm, isolated.
Rated 120 mA at 130 Vac or 170 Vdc.
Analog transmitter output, 16-bit, user scalable and isolated. User selectable 4-20 mA,
0-20 mA or 0-10V levels.
Universal AC power supply for 85-264 Vac.
Easy Transmitter programming is via
Laurel's Instrument Setup Software,
which runs on a PC under MS Windows. This software can be downloaded from this website at no charge. The required transmitter-to-PC interface cable is available from
Laurel (P/N CBL04).
Specifications
Laureate Modbus & Serial Output RTD
Temperature Transmitter
RTD
Metal
Alpha
R
at
0°C
R at top
of range
Excitation
Current
Range
Conformity
Error
Platinum
0.003850
(DIN)
100Ω
390.48Ω
at 850°C
256 μA
-200°C to
+850°C
-328°F to +1562°F
±0.03°C
±0.05°F
Platinum
0.003902
(ANSI)
100Ω
394.36Ω
at 850°C
256 μA
-200°C to
+850°C
-328°F to +1168°F
±0.04°C
±0.07°F
Nickel
0.00672
120Ω
380.31Ω
at 260°C
256 μA
-80°C
to +260°C
-112°F to +500°F
±0.05°C
±0.09°F
Copper
0.00427
9.035Ω
19.116Ω
at 260°C
5.0 mA
-97°C
to +260°C
-143°F to +500°F
±0.05°C
±0.09°F
RTD Input
Calibration, Pt
100 DIN
Calibration, Pt 100 ANSI
Configuration
Excitation current
Overall accuracy
Span tempco
Zero tempco
Sensor lead resistance
tempco per conductor
Over-voltage protection
Open sensor indication
IEC 751 (IPTS-68)
NIST Monograph 126
2, 3 or 4-wire connection
0.2 mA
±0.01 of full scale ±2 counts
±0.003% of reading/ºC
±0.03 deg/deg
2-wire, 10 mdeg/W/deg up to 10 W
3 & 4-wire, 10 mdeg/W/deg up to 100 W
125 Vac
0 mA or > 20mA output, selectable
Serial Data Output
(standard)
Signal Types
Data Rates
Output Isolation
Serial Protocols
Modbus Modes
Modbus Compliance
Digital Addressing
RS232 or RS485 (half or full duplex)
300, 600, 1200, 2400, 4800, 9600, 19200 baud
250V rms working, 2.3 kV rms per 1 min test
Modbus RTU, Modbus ASCII, Laurel ASCII
RTU or ASCII
Modbus over Serial Line Specification V1.0 (2002)
247 Modbus addresses.
Up to 32 devices on an RS485 line w/o a repeater.
4-20 mA, 0-20 mA, 0-10 Vdc (jumper selectable)
10V ( 0-500 ohm load )
2 mA ( 5 kOhm load or higher)
16 bits (65,536 steps)
0.02% of output span plus conversion accuracy
250V rms working, 2.3 kV rms per 1 minute test
Dual Relay Output (standard)
Relay Type
Load Rating
Two solid state relays, SPST, normally open,
Form A
130 mA at 140 Vac or 180 Vdc
Power Input
Standard Power
Low Power Option
Power Frequency
Power Isolation
Power Consumption
85-264 Vac or 90-300 Vdc (DC operation not UL
approved)
10-48 Vdc or 12-32 Vac
DC or 47-63 Hz
250V rms working, 2.3 kV rms per 1 min test
2W typical
Mechanical
Dimensions
Mounting
Electrical Connections
120 x 101 x 22.5 mm
35 mm rail per DIN EN 50022
Plug-in screw-clamp connectors
Environmental
Operating Temperature
Storage Temperature
Relative Humidity
Cooling Required
0°C to 55°C
-40°C to 85°C
95% at 40°C, non-condensing
Mount transmitters with ventilation holes at top and bottom.
Leave 6 mm (1/4") between transmitters, or force air with a fan.
Pinouts
Laureate Modbus & Serial Output RTD
Temperature Transmitter
RTD hookup
can be via 2, 3 or 4 wires to the J5 connector. The transmitter applies an excitation
current of 196 μA (Pt 100 and Ni 120) or 5 mA (Cu 10).
In 4-wire hookup, different
pairs of leads are used to apply the excitation current and sense the
voltage drop across the RTD, so that the IR drop across the excitation leads
is not a factor.
In 3-wire hookup, the transmitter senses the
combined voltage drop across the RTD plus two excitation leads. It also
senses the voltage drop across one excitation lead, and then subtracts twice
this voltage from the combined total. This technique effectively subtracts
all lead resistance and compensates for ambient temperature changes if the
two excitation leads are identical.
In 2-wire hookup,
the transmitter senses the combined voltage drop across the RTD and both lead wires.
The voltage drop across the lead wires can be measured by shorting out the RTD during
transmitter setup,
and this voltage is then automatically subtracted from the combined total.
However, changing resistance of the lead wires due to ambient temperature
changes will not be compensated.
Operation as a
Fast ON/OFF Controller
or Supervisory Monitor
With the optional dual solid state relay output
option, which has a typical response
time of only 17 ms, Laureate temperature meters
and transmitters can
serve as extremely fast and accurate ON/OFF controllers
for closed-loop temperature control.
They can also serve as
supervisory process monitors and provide alarms or shutoffs when processes exceed normal
limits.
Multiple setpoint operating modes are
individually selectable for each relay, as explained in the
dual-setpoint controller page. Relay duty cycles and chatter can be minimized with programmable hysteresis and
time delays. A band deviation operating mode can be
selected for each relay, where an alarm is generated whenever the reading is a selected
number of counts above or below the setpoint. With Modbus, relay operation
can be non-latching or latching, with reset provided by digital commands.
Ordering
Guide
Laureate Modbus & Serial Output RTD
Temperature Transmitter Click on the radio buttons to build a model number with pricing (shown below the Ordering Guide).
Digital
calibration of all
RTD ranges is performed the factory, with calibration data stored
in EEPROM on the signal conditioner board. This allows signal
conditioner boards and ranges to be changed in the field with no need for
recalibration. Open sensor indication is standard and may be set up to indicate either upscale or
downscale. RTD excitation is provided by the transmitter. RTD connections can be of the 2-, 3-
or 4-wire type. With 3- and 4-wire connections, the transmitter automatically compensates for
lead resistance of the sensor.
With the optional dual solid state relay output
option, which has a typical response
time of only 17 ms, Laureate temperature meters
and transmitters can
serve as extremely fast and accurate ON/OFF controllers
for closed-loop temperature control.
They can also serve as
supervisory process monitors and provide alarms or shutoffs when processes exceed normal
limits. 