WLS-TEMP
Wireles Sensor Measurement

Specifications

Document Revision 1.2
February 2013
© Copyright 2013

WLS-TEMP Specifications
All specifications are subject to change without notice.
Typical for 25 °C unless otherwise specified.
Specifications in italic text are guaranteed by design.

Analog input
Table 1. Generic analog input specifications
Parameter

Condition

Specification

A/D converters

Four dual 24-bit, Sigma-Delta type

Number of channels

8 differential

Input isolation

500 VDC minimum between field wiring andUSB interface
Software programmable to match sensor type±0.080 V
0 to 0.5 V
0 to 2 V
0 to 2.5 V±25 V power on±40 V power off
5 GΩ, min

Channel configuration
Differential input voltage
range

Absolute maximum input
voltage

Thermocouple
RTD
Thermistor
Semiconductor sensor±C0x through ±C7x relative to GND

Input impedance
Input leakage current
Normal mode rejection ratio
Common mode rejection
ratio
Resolution

Open thermocouple detect disabledOpen thermocouple detect enabled
fIN =60 Hz
fIN =50 Hz/60 Hz

30 nA max
105 nA max
90 dB min
100 dB min
24 bits

No missing codes
Input coupling

24 bits
DC

Warm-up time

30 minutes min

Open thermocouple detect

Automatically enabled when the channel pair isconfigured for thermocouple sensor.
The maximum open detection time is 3 seconds.
±0.25 °C typ,±0.5 °C max–1.0 °C to +0.5 °C max

CJC sensor accuracy

15 °C to 35 °C
0 °C to 70 °C

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WLS-TEMP

Channel configurations
Table 2. Channel configuration specifications
Sensor Category

Condition

Max number of
sensors (all channels
configured alike)

Thermocouple
Semiconductor sensor

J, K, S, R, B, E, T, or N

8 differential channels
8 differential channels

RTD and thermistor

2-wire input configuration with a single sensor per channelpair
2-wire input configuration with two sensors per channel pair
3-wire configuration with a single sensor per channel pair
4-wire input configuration with a single sensor per channelpair
4-wire input configuration with two sensors per channel pair

4 differential channels

Disabled

8 differential channels
4 differential channels
4 differential channels
8 differential channels

Note 1: Internally, the device has four dual-channel, fully differential A/Ds providing a total of eight

differential channels. The analog input channels are therefore configured in four channel pairs with
CH0/CH1 sensor inputs, CH2/CH3 sensor inputs, CH4/CH5 sensor inputs, and CH6/CH7 sensor
inputs paired together. This "channel-pairing" requires the analog input channel pairs be configured tomonitor the same category of temperature sensor. Mixing different sensor types of the same category(such as a type J thermocouple on channel 0 and a type T thermocouple on channel 1) is valid.
Note 2: Channel configuration information is stored in the EEPROM of the isolated microcontroller by thefirmware whenever any item is modified. Modification is performed by commands issued over USB or
wireless from an external application, and the configuration is made non-volatile through the use of the
EEPROM.
Note 3: The factory default configuration is Disabled. The Disabled mode will disconnect the analog inputs
from the terminal blocks and internally ground all of the A/D inputs. This mode also disables each of
the current excitation sources.

Compatible sensors
Table 3. Compatible sensor type specifications
Parameter

Condition

Thermocouple

J: –210 °C to 1200 °C
K: –270 °C to 1372 °C
R: –50 °C to 1768 °C
S: –50 °C to 1768 °C
T: –270 °C to 400 °C
N: –270 °C to 1300 °C
E: –270 °C to 1000 °C
B: 0 °C to 1820 °C
100 Ω PT (DIN 43760: 0.00385 ohms/ohm/°C)
100 ΩPT (SAMA: 0.003911 ohms/ohm/°C)
100 Ω PT (ITS-90/IEC751:0.0038505 ohms/ohm/°C)Standard 2,252 Ω through 30,000 Ω
LM35, TMP35 or equivalent

RTD

Thermistor
Semiconductor / IC3

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WLS-TEMP

Accuracy
Thermocouple measurement accuracy
Table 4. Thermocouple accuracy specifications, including CJC measurement error
Sensor TypeMaximum error (°C)

Typical error (°C)

Temperature range (°C)

J

±1.499±0.643±1.761±0.691±2.491±1.841±2.653±1.070±1.779±0.912±1.471±0.639±1.717±0.713±1.969±0.769±0.507±0.312±0.538±0.345±0.648±0.399±0.650±0.358±0.581±0.369±0.462±0.245±0.514±0.256±0.502±0.272–210 to 0
0 to 1200–210 to 0
0 to 1372–50 to 250
250 to 1768.1–50 to 250
250 to 1768.1
250 to 700
700 to 1820
–200 to 0
0 to 1000–200 to 0
0 to 600–200 to 0
0 to 1300

K
S
R
B
E
T
N

Note 4: Thermocouple measurement accuracy specifications include linearization, cold-junction compensationand system noise. These specs are for one year, or 3000 operating hours, whichever comes first, andfor operation of the device between 15 °C and 35 °C. For measurements outside this range, add ±0.5
degree to the maximum error shown. There are CJC sensors on each side of the module. The accuracy
listed above assumes the screw terminals are at the same temperature as the CJC sensor. Errors shown
do not include inherent thermocouple error. Please contact your thermocouple supplier for details on
the actual thermocouple error.
Note 5: Thermocouples must be connected to the device such that they are floating with respect to GND (pins9, 19, 28, 38). The device GND pins are isolated from earth ground, so connecting thermocouple
sensors to voltages referenced to earth ground is permissible as long as the isolation between the GND
pins and earth ground is maintained.
Note 6: When thermocouples are attached to conductive surfaces, the voltage differential between multiple
thermocouples must remain within ±1.4 V. For best results we recommend the use of insulated or
ungrounded thermocouples when possible.

Semiconductor sensor measurement accuracy
Table 5. Semiconductor sensor accuracy specifications
Sensor Type

Temperature Range (°C)

Maximum Accuracy Error

LM35, TMP35 orequivalent–40 to 150±0.50Note 7: Error shown does not include errors of the sensor itself. These specs are for one year while operationof the device is between 15 °C and 35 °C. Please contact your sensor supplier for details on the actual
sensor error limitations.

4Specifications

WLS-TEMP

RTD measurement accuracy
Table 6. RTD measurement accuracy specifications
RTD

SensorTemperature (°C)

Maximum Accuracy Error (°C)
Ix+ = 210 µA

Typical Accuracy Error (°C)
Ix+ = 210 µA

PT100, DIN, US or
ITS-90–200 to –150
–150 to –100
–100 to 0
0 to 100
100 to 300
300 to 600

±2.85
±1.24
±0.58
±0.38
±0.39
±0.40

±2.59
±0.97
±0.31
±0.11
±0.12
±0.12

Note 8: Error shown does not include errors of the sensor itself. The sensor linearization is performed using a

Callendar-Van Dusen linearization algorithm. These specs are for one year while operation of thedevice is between 15 °C and 35 °C. The specification does not include lead resistance errors for 2-wire
RTD connections. Please contact your sensor supplier for details on the actual sensor error limitations.
Note 9: Resistance values greater than 660 Ω cannot be measured by the device in the RTD mode. The 660 Ω
resistance limit includes the total resistance across the current excitation (±Ix) pins, which is the sum of
the RTD resistance and the lead resistances.
Note 10:
For accurate three wire compensation, the individual lead resistances connected to the ±Ix pins
must be of equal value.

Thermistor measurement accuracy
Table 7. Thermistor measurement accuracy specifications
Thermistor

Temperature range (°C)

Maximum accuracy error (°C)
Ix+ = 10 µA

2252 Ω

–40 to120±0.05

3000 Ω
5000 Ω

–40 to120–35 to120

±0.05
±0.05

10000 Ω30000 Ω–25 to120–10 to120

±0.05
±0.05

Note 11:

Error shown does not include errors of the sensor itself. The sensor linearization is performed
using a Steinhart-Hart linearization algorithm. These specs are for one year while operation of thedevice is between 15 °C and 35 °C. The specification does not include lead resistance errors for 2-wirethermistor connections. Please contact your sensor supplier for details on the actual sensor error
limitations. Total thermistor resistance on any given channel pair must not exceed 180 k Ω. Typicalresistance values at various temperatures for supported thermistors are shown in Table 8.
Table 8. Typical thermistor resistance specifications

Temp
(°C)

2252 Ω
thermistor

3000 Ω
thermistor

5 kΩ
thermistor

10 kΩ
thermistor

30 kΩ
thermistor

–40
–35

76 kΩ
55 kΩ

101 kΩ
73 kΩ

168 kΩ
121 kΩ

240 kΩ (Note 12)
179 kΩ

885 kΩ (Note 12)649 kΩ (Note 12)

–30
–25

40 kΩ
29 kΩ

53 kΩ
39 kΩ

88 kΩ
65 kΩ

135 kΩ
103 kΩ

481 kΩ (Note 12)
360 kΩ (Note 12)

–20
–15

22 kΩ
16 kΩ

29 kΩ
22 kΩ

49 kΩ
36 kΩ

79 kΩ
61 kΩ

271 kΩ (Note 12)
206 kΩ (Note 12)

–10
–5

12 kΩ
9.5 kΩ

17 kΩ
13 kΩ

28 kΩ
21 kΩ

48 kΩ
37 kΩ

158 kΩ
122 kΩ

0

7.4 kΩ

9.8 kΩ

16 kΩ

29 kΩ

95 kΩ

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WLS-TEMP

Resistance values greater than 180 kΩ cannot be measured by the device in the thermistor mode.
The 180 kΩ resistance limit includes the total resistance across the current excitation (±Ix) pins, whichis the sum of the thermistor resistance and the lead resistances.
Note 13:
For accurate three wire compensation, the individual lead resistances connected to the ±Ix pins
must be of equal value.
Note 12:

Throughput rate to PC (USB or wireless)
Table 9. Throughput rate specifications
Number of input channels

Maximum throughput

1
2
3
4
5
6
7
8

2 Samples/second
2 S/s on each channel, 4 S/s total
2 S/s on each channel, 6 S/s total
2 S/s on each channel, 8 S/s total
2 S/s on each channel, 10 S/s total
2 S/s on each channel, 12 S/s total
2 S/s on each channel, 14 S/s total
2 S/s on each channel, 16 S/s total

Note 14:

The analog inputs are configured to run continuously. Each channel is sampled twice per second.
The maximum latency between when a sample is acquired and the temperature data is provided by thedevice is approximately 0.5 seconds

Digital input/output
Table 10. Digital input/output specifications
Parameter

Specification

Digital type
Number of I/O
Configuration

CMOS
8 (DIO0 through DIO7)
Independently configured for input or output.
Power on reset is input mode unless bit is configured for alarm.
All pins pulled up to +5 V via 47 kΩ resistors (default). Pull down to ground (GND) alsoavailable.
 Digital input: 50 port reads or single bit reads per second, typ Digital output: 100 port writes or single bit writes per second, typ
2.0 V min, 5.5 V absolute max
0.8 V max, –0.5 V absolute min
0.7 V max

Pull up/pull-down
configuration
Digital I/O transfer rate
(software paced)
Input high voltage
Input low voltage
Output low voltage(IOL = 2.5 mA)
Output high voltage(IOH = –2.5 mA)
Note 15:

3.8 V minAll ground pins are common and are isolated from earth ground. If a connection is made to earth
ground when using digital I/O and conductive thermocouples, the thermocouples are no longer
isolated. In this case, thermocouples must not be connected to any conductive surfaces that may bereferenced to earth ground.

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WLS-TEMP

Temperature alarms
Table 11. Temperature alarm specifications
Parameter

Specification

Number of alarms
Alarm functionality

8 (one per digital I/O line)
Each alarm controls its associated digital I/O line as an alarm output. The input to each
alarm may be any of the analog temperature input channels. When an alarm is enabled, its
associated I/O line is set to output (after the device is reset) and driven to the appropriate
state determined by the alarm options and input temperature. The alarm configurations are
stored in non-volatile memory and are loaded at power on. Alarms will function both inwireless mode and while attached to USB.
 Alarm when input temperature > T1
 Alarm when input temperature > T1, reset alarm when input temperature goes below T2
 Alarm when input temperature < T1
 Alarm when input temperature < T1, reset alarm when input temperature goes above T2
 Alarm when input temperature is < T1 or > T2
Note: T1 and T2 may be independently set for each alarm.
 Disabled, digital I/O line may be used for normal operation
 Enabled, active high output (digital I/O line goes high when alarm conditions met) Enabled, active low output (digital I/O line goes low when alarm conditions met)
1 second

Alarm input modes

Alarm output modes

Alarm update rate

MemoryTable 12. Memory specifications
Parameter

Specification

EEPROM

1,024 bytes isolated micro reserved for sensor configuration
256 bytes USB micro for external application use

Microcontroller
Table 13. Microcontroller specifications
Parameter

Specification

Type

Three high performance 8-bit RISC microcontrollers

Wireless communications
Table 14. Wireless Communications specifications
Parameter

Specification

Communication standard
Range

IEEE 802.15.4, ISM 2.4GHz frequency band, non-beacon, point-to-point
Indoor/urban: Up to 150' (50 m)
Outdoor RF line-of-sight: Up to 1/2 mile (750 m)
10 mW (10 dBm)
–100 dBm (1% packet error rate)
12 direct sequence channels available, channels 12 – 23 (2.410 – 2.465 GHz)
(software selectable)
16-bit PAN (personal area network) IDs per channel (software selectable)
64-bit device address
128-bit AES (software selectable)

Transmit power output
Receiver sensitivity
RF channels
Addressing
Encryption

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Specifications

WLS-TEMP

Contains FCC ID: OUR-XBEEPRO. The enclosed device complies with Part 15 of the FCC
Rules. Operation is subject to the following two conditions: (i.) this device may not cause harmfulinterference and (ii.) this device must accept any interference received, including interference that may
cause undesired operation.
Note 17:
Canada: Contains Model XBee Radio, IC: 4214A-XBEEPRO
Note 16:

Caution! To satisfy FCC RF exposure requirements for mobile transmitting devices, a separation distanceof 20 cm or more should be maintained between the antenna of this device and persons during
device operation. To ensure compliance, operations at closer than this distance is notrecommended. The antenna used for this transmitter must not be co-located in conjunction withany other antenna or transmitter.

USB +5V voltage
Table 15. USB +5V voltage specifications
Parameter

Specification

USB +5V (VBUS) input voltage range

4.75 V min to 5.25 V max

Power
Table 16. Power specifications
Parameter

Condition

Specification

Connected to USB
Supply current
User +5V output voltage range(terminal block pin 21 and 47)
User +5V output current(terminal block pin 21 and pin 47)
Isolation

Connected to a self-powered hub. (Note 18)

500 mA max
4.75 V min to
5.25 V max
10 mA max

Measurement system to PC

500 VDC min

Connected to a self-powered hub. (Note 18)

Wireless Communications operation
Supply current

500 mA max

AC Adapter Power Supply (used for remote wireless communications operation)
Standalone power supply

USB power adapter
2.5 Watt USB adapter withinterchangeable plugs(Includes plug for USA)
5 V ±5%
2.5 W
100 VAC to 240 VAC
50 Hz to 60 Hz
0.2 A

Output voltage
Output wattage
Input voltage
Input current
Note 18:

Self-Powered Hub refers to a USB hub with an external power supply. Self-powered hubs allow aconnected USB device to draw up to 500 mA. This device may not be used with bus-powered hubs dueto the power supply requirements.
Root Port Hubs reside in the PC USB Host Controller. The USB port(s) on your PC are root port hubs.
All externally powered root port hubs (desktop PC) provide up to 500 mA of current for a USB device.
Battery-powered root port hubs provide 100 mA or 500 mA, depending upon the manufacturer. A
laptop PC that is not connected to an external power adapter is an example of a battery-powered root
port hub.

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WLS-TEMP

USB specifications
Table 17. USB specifications
Parameter

Specification

USB device type
Device compatibility

USB 2.0 (full-speed)
USB 1.1, USB 2.0
Bus powered, 500 mA consumption max

USB cable type

A-B cable, UL type AWM 2725 or equivalent. (min 24 AWG VBUS/GND,
min 28 AWG D+/D–)
3 m (9.84 ft) max

USB cable length

Current excitation outputs (Ix+)
Table 18. Current excitation output specifications
Parameter

Specification

Configuration

4 dedicated pairs:±I1: CH0/CH1±I2: CH2/CH3±I3: CH4/CH5±I4: CH6/CH7
Thermistor: 10 µA typ
RTD: 210 µA typ±5% typ
200 ppm/°C
2.1 ppm/V max
0.3 ppm/V typ
3.90 V max–0.03 V min

Current excitation output ranges
Tolerance
DriftLine regulation
Load regulation
Output compliance voltage (relative to
GND pins 9, 19, 28, 38)

The device has four current excitation outputs, with ±I1 dedicated to the CH0/CH1 analog inputs,±I2 dedicated to CH2/CH3, ±I3 dedicated to CH4/CH5, and ±I4 dedicated to CH6/CH7. The excitation
output currents should always be used in this dedicated configuration.
Note 20:
The current excitation outputs are automatically configured based on the sensor selected(thermistor or RTD).
Note 19:

Environmental
Table 19. Environmental specifications
Parameter

Specification

Operating temperature range
Storage temperature range
Humidity

0 °C to 70 °C–40 °C to 85 °C
0% to 90% non-condensing

Mechanical
Table 20. Mechanical specifications
Parameter

Specification

Dimensions (L × W × H)User connection length

128.52 x 88.39 × 35.56 mm (5.06 × 3.48 × 1.43 ft)
3 m (9.84 ft) max

9Specifications

WLS-TEMP

LED / button configuration
Table 21. LED configuration
Parameter

Specification

Command LED

Green LED – indicates a command was received by the device (either USB or
wireless)Three green LED bar graph.
LEDs turn on when receiving a wireless message and stay on for approximately
1 second after the end of the message. The LEDs indicate the amount of fademargin present in an active wireless link. Fade margin is defined as the difference
between the incoming signal strength and the receiver sensitivity of the device.
 3 LEDs on: Very strong signal (>30 dB fade margin) 2 LEDs on: Strong signal (>20 dB fade margin) 1 LED on: Moderate signal (>10 dB fade margin)
 0 LED on: Weak signal (<10 dB fade margin)
Green LED: indicates that the internal RF module is powered.
Yellow LED: indicates transmitting data over the wireless link.
Red LED: indicates receiving data over the wireless link.
Firmware-defined; this revision executes an LED test.

Received Signal Strength Indicator(RSSI) LEDs

Wireless Power LED
Transmit LED
Receive LED
Button10

Specifications

WLS-TEMP

Screw terminal connector
Table 22. Screw terminal connector specifications
Connector type
Wire gauge range

Screw terminal
16 AWG to 30 AWG
Table 23. Screw terminal pinout

Pin
1
2
3
4
5
6
7
8
9
10

Signal Name
I1+
NC
C0H
C0L
4W01
IC01
C1H
C1L
GND
I1–

Pin Description
CH0/CH1 current excitation source
No connection
CH0 sensor input (+)
CH0 sensor input (–)
CH0/CH1 4-wire, 2 sensor common
CH0/CH1 2-sensor common
CH1 sensor input (+)
CH1 sensor input (–)
GroundCH0/CH1 current excitation return

Pin
27
28
29
30
31
32
33
34
35
36

CJC sensor
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26

I2+
NC
C2H
C2L
4W23
IC23
C3H
C3L
GND
I2–
+5V
GND
DIO0
DIO1
DIO2
DIO3

Signal Name Pin Description
I4–
CH6/CH7 current excitation return
GND
GroundC7L
CH7 sensor input (–)
C7H
CH7 sensor input (+)
IC67
CH6/CH7 2 sensor common
4W67
CH6/CH7 4-wire, 2 sensor common
C6L
CH6 sensor input (–)
C6H
CH6 sensor input (+)
NC
No connection
I4+
CH6/CH7 current excitation source
CJC sensor

CH2/CH3 current excitation source
No connection
CH2 sensor input (+)
CH2 sensor input (–)
CH2/CH3 4-wire, 2 sensor common
CH2/CH3 2 sensor common
CH3 sensor input (+)
CH3 sensor input (–)
GroundCH2/CH3 current excitation return+5V output
GroundDIO channel 0
DIO channel 1
DIO channel 2
DIO channel 3

11

37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52

I3–
GND
C5L
C5H
IC45
4W45
C4L
C4H
NC
I3+
+5V
GND
DIO7
DIO6
DIO5
DIO4

CH4/CH5 current excitation returnCH5 sensor input (–)
CH5 sensor input (+)
CH4/CH5 2 sensor common
CH4/CH5 4-wire, 2 sensor common
CH4 sensor input (–)
CH4 sensor input (+)
No connection
CH4/CH5 current excitation source+5V output
GroundDIO channel 7
DIO channel 6
DIO channel 5
DIO channel 4

Measurement Computing Corporation
10 Commerce Way
Suite 1008
Norton, Massachusetts 02766(508) 946-5100
Fax: (508) 946-9500
E-mail: info@mccdaq.com
www.mccdaq.com
WLS-TEMP-spec.docx