Specifications

Input specifications

Standard inputs, (normal mode, reversing1)
 
 Sensor temperature coefficient Input
range
Excitation
current
Display
resolution
Measurement
resolution
Electronic
accuracy
(at 25 °C)
Measurement temperature coefficient
Diode
Negative  0 V to 7.5 V 10 µA ±0.05%100 µV20 µV±320 µV ±0.01% of rdg(20 µV + 0.0015% of rdg)/°C1
PTC RTD
1 mA
Positive0 Ω to 1 kΩ1 mA10 mΩ20 mΩ±0.04 Ω ±0.02% of rdg(1 mΩ + 0.0015% of rdg)/°C1
NTC RTD
10 mV
Negative0 Ω to 10 Ω1 mA0.1 mΩ0.1 mΩ + 0.002% of rdg±0.002 Ω ±0.06% of rdg(0.1 mΩ + 0.0015% of rdg)/°C1
0 Ω to 30 Ω300 µA0.1 mΩ0.3 mΩ + 0.002% of rdg±0.002 Ω ±0.06% of rdg(0.1 mΩ + 0.0015% of rdg)/°C1
0 Ω to 100 Ω100 µA1 mΩ1 mΩ + 0.002% of rdg±0.01 Ω ±0.04% of rdg(0.1 mΩ + 0.0015% of rdg)/°C1
0 Ω to 300 Ω30 µA1 mΩ3 mΩ + 0.002% of rdg±0.01 Ω ±0.04% of rdg(0.3 mΩ + 0.0015% of rdg)/°C1
0 Ω to 1 kΩ10 µA10 mΩ10 mΩ + 0.002% of rdg±0.01 Ω ±0.04% of rdg(1 mΩ + 0.0015% of rdg)/°C1
0 Ω to 3 kΩ3 µA10 mΩ30 mΩ + 0.002% of rdg±0.01 Ω ±0.04% of rdg(3 mΩ + 0.0015% of rdg)/°C1
0 Ω to 10 kΩ1 µA100 mΩ100 mΩ + 0.002% of rdg±1.0 Ω ±0.04% of rdg(10 mΩ + 0.0015% of rdg)/°C1
0 Ω to 30 kΩ300 nA100 mΩ300 mΩ + 0.002% of rdg±2.0 Ω ±0.04% of rdg(30 mΩ + 0.0015% of rdg)/°C1
0 Ω to 100 kΩ100 nA1 Ω1 Ω + 0.002% of rdg±10.0 Ω ±0.04% of rdg(100 mΩ + 0.0015% of rdg)/°C1
1 Current reversal used only for resitive ranges
2
Rated temperature coefficient from 15 °C to 35 °C, reduced accuracy from -20 °C to 50 °C
Sensor Input Configuration
RTD Diode
Measurement type 4-lead differential 4-lead differential
Excitation Constant current with current reversal 10 μA constant current
Supported sensors Cernox®, platinum, germanium, carbon-glass, rhodium-iron, and Rox™ Silicon, GaAlAs
Standard curves supplied LSCI PT-100,
IEC PT-100,
IEC PT-1000
LSCI DT-670
LSCI DT-470
Input connector 5-pin terminal plug 5-pin terminal plug
Thermometry
Number of inputs 2 (Model 240-2P)
8 (Model 240-8P)
Isolation Sensor inputs isolated from other circuits but not each other
Input accuracy Sensor dependent, refer to Input Specifications table
Measurement resolution Sensor dependent, refer to Input Specifications table
Measurement speed
240-2P 240-8P
Normal mode    
Update rate 10 rdg/s1 2.5 rdg/s1,2
Filter 100 ms 100 ms
High speed mode    
Update rate 10 to 1000 rdg/s N/A
Filter 1 to 100 ms3 N/A
1 Update rate is halved when an input is on the 100 kΩ range with current reversal enabled
2
All inputs enabled
3 Filter settings are tied to the update rate, (filter = 1000/update rate)

Temperature conversion Lake Shore calibration curves (linear interpolation)
User curves Each input has storage for one 200-point curve
Reporting units K, °C, °F, V, Ω
Digital I/O - Profibus
Protocol DP-V0
Baud rates 9.6 k, 19.2 k, 45.45 k, 93.75 k, 187.5 k, 500 k, 1.5 M, 3 M, 6 M, 12 M (auto baud-rate detect)
Identification number 0x0F84
Reading data format Single precision float (32-bit)
Reading rate Matches update rate of the instrument
Digital I/O - USB
Function Emulates a standard RS-232 serial port
Baud rate 115,200, 8 data bits, 1 stop bit, no parity, no handshaking
Connector USB micro-B
Reading rate Matches update rate of the instrument
Management
Module configuration Module configured over USB interface
Configuration software MeasureLINK™ (free download, supported on Windows 7, 8, and 10)
Firmware update Firmware updated over USB port
Display
Display128 × 32 pixel OLED
Display unitsK, °C, °F, V, Ω
Display update rate2 rdg/s
240-2P240-8P
Displayed readings22
Readings cyclingFixed (no cycling)3 second hold per pair
Temperature display resolution0.0001° from 0° to 9.9999°,
0.001° from 10° to 99.999°,
0.01° from 100° to 999.99°,
0.1° above 1000°
Sensor units display resolutionSensor dependent, to 5 digits
LED annunciatorsModule status and communication status
Power supply
ConnectionScrew terminal
Voltage requirement24 VDC, ±10%
Current requirement100 mA per connected module
Power distributionMaximum 20 units connected through the DIN rail backplane connector (power supply must be able to source required current)
Internal protectionOver-voltage, under-voltage, and reverse polarity protection
Physical
Case materialPolyamide
Mounting35 mm DIN rail (EN 50022)
Water ingressIP20: not protected against harmful ingress of water
Case inflammabilityClass V0 according to UL 94
Sensor connector wire size16 to 28 AWG
Power connector wire size12 to 24 AWG
Size22.5 mm W × 115 mm H × 100 mm L (240-2P)
90 mm W × 115 mm H × 100 mm L (240-8P)
Weight120 g (240-2P)
300 g (240-8P)
Enviromental
ComplianceRoHS; CE
Operating temperature15 °C to 35 °C at rated accuracy, -20 °C to 50 °C at reduced accuracy
Storage temperature-40 °C to 85 °C
Relative humidity0 to 70% at rated accuracy, reduced accuracy up to 95%, non-condensing