PL-TW PRECISE-LOG Thermocouple Data Logger

PL-TW PRECISE-LOG Thermocouple Data Logger

PL-TW is an 8-channel, battery powered, standalone and WIFI-enabled thermocouple data logger. The logger records eight external thermocouples and saves data in 8-MB memory. 

Embedded WIFI module allows remote data monitoring and downloading. The data logger can be enabled by Modbus TCP protocol and become a Modbus TCP server.

16-bit ADC makes it well suited for science and laboratory applications where precise and accurate measurements are critical. 

Its aluminum enclosure makes it excellent in the harshest industrial environment. 

Simply power the logger in WIFI covered area and access it from your computer for configuration, downloading, graph viewing and more... 

Features:

  • 16-bit analog-to-digital converter
  • Cold-Junction Compensation
  • 8 megabyte memory size
  • Both USB and WIFI comm. interfaces with baud rate of 115200 bps
  • Programmable input ranges (73mV, 18mV)
  • Over 10 years of battery life
  • Powerful software for configuration, downloading, plotting, analysis and alarm reporting
  • Support Modbus TCP protocol
  • Wide sampling interval selections (one second to 12 hours)
  • Rugged aluminum enclosure

Documents

PRECISE-LOG Thermocouple Data Logger Specifications

SiteView Specifications

How to configure WIFI settings


General
Product Name PRECISE-LOG Thermocouple Data Logger
Model PL-TW
Inputs
Connection Plugable terminal block for eight external channels
Channels One on-board thermistor temperature (-40°C ~ 70°C, -40°F ~ 158°F)
Eight external thermocouple.
Programmable input selections for each external channel:
-8 ~ +73 mV
-2 ~ +18 mV
Resolution 0.0018%
Accuracy Thermocouple: ±0.1% ~ 0.2% + T/C Accuracy
Temperature Compensation On-board thermistor
Over-Voltage Protection Up to ± 20 VDC
Alarms
Channel Alarms Two editable alarm thresholds per channel.
Alarm Indicator On-board LED becomes red when in alarm condition.
On-board Memory
Size 8 Mega bytes (4MB readings).
Data Retention Over 20 years.
Sampling
Sampling Interval 1 second to 12 hours user selectable.
Logging Mode Stop recording or FIFO when memory is full.
Logging Activation Programmable instant, start delay or field push button activation.
Communications
Interface USB (Mini-USB-B) (USB-A-mini USB-B Cable included)
WIFI (USB 5 VDC wall power adapter included)
WIFI Module Standard: 802.11b/g/n,
Frequency Range: 2.412 - 2.484GHz
Transmit Power: 11-18 dBm
Receive Sensitivity: -82 to -93 dBm
Security: WEP/WPA-PSK/WPA2-PSK
Encryption: WEP64/WEP128/TKIP/AES
Can be Enabled/Disabled by SiteView software
Baud Rate 115200 bps.
Battery
Power Built-in 3.6V Lithium Battery.
Battery Life 10 years based on 1 minute sampling interval in stand-alone mode.
Software
SiteView (Sold separately) Configuration, downloading, plotting, real-time view, custom calibration and custom equation.
Software Requirement Computer with 1.0 GHz or faster processor
1 GB Memory or higher
10 GB of available hard-drive space or higher
Windows XP with SP2 or later, Vista, Window 7,8,10
At least one USB port or one COM port.
Physical
Material Aluminum enclosure.
Dimension 88 X 64.2 X 24 mm (3.46 X 2.53 X 0.95 inches).
Weight 200g
Mounting Probe/wall-mount holes for hanging/mounting.
Others
LED Indicator Tri-Color LED: (can be disabled for power saving)
Normal Sampling: light green when sampling.
Alarm: red when sampling.
Low Battery: amber when sampling.
Operating Environment -40 ~ +70 °C (-40 °F ~ 158 °F), 0 ~ 95% RH non-condensing.
Clock Accuracy ±1 mintue per month.
Approval CE, FCC

Logger Memory Capacity

Sampling Interval Enabled Channel Logging Capacity
1 minute 1 8 years
1 minute 2 4 years
1 minute 8 1 year
10 seconds 1 485 days
10 seconds 2 242 days
10 seconds 8 60 days
1 second 1 48 days
1 second 2 24 days
1 second 8 6 days

Programmable Channel Range Specifications:

Range: -8mV ~ +73mV Accuracy: ±0.1% (0.08 mV)@ 25°C + Temperature Compensation Accuracy
Thermocouple Type Temperature Range (°C) Resolution (°C) Accuracy (°C)
Type E -171 to +955 0.02 0.56
Type J -205 to +1200 0.027 0.73
Type K -270 to +1372 0.04 1.07
Type N -270 to +1300 0.045 1.21
Type T -270 to +400 0.037 1.00
Type C 0 to 2320 0.1 2.5
Type S -50 to 1768 0.04 3.85
Range: -2mV ~ +18mV Accuracy: ±0.15% (0.03 mV) @ 25°C + Temperature Compensation Accuracy
Type E -35 to 260 0.005 0.45
Type J -40 to 330 0.0062 0.56
Type K -53 to 437 0.0082 0.74
Type N -81 to 532 0.01 0.92
Type T -55 to 353 0.008 0.62
Type B 0 to 1820 0.03 3.95
Type R -50 to 1539 0.026 2.62
Type S -50 to 1704 0.03 2.9
Type C 0 to 986 0.0164 1.65

Modbus TCP protocol was added to all PRECISE-LOG series of data loggers with firmware version 2.06. A Modbus master/client can read one or more Input Registers and Holding Registers available in a PRECISE-LOG data logger through Modbus TCP communications.

The below specifications list all supported commands and available registers PL-TW data logger supports:

Input Registers:

An Input Register stores a 16-bit integer for a channel’s real-time reading. To read one or more 16-bit Input register data, use function code 4.

Register Description Type Range
0 CH0 Value Unsigned Integer 0 - 65535
1 CH1 Value Unsigned Integer 0 - 65535
2 CH2 Value Unsigned Integer 0 - 65535
3 CH3 Value Unsigned Integer 0 - 65535
4 CH4 Value Unsigned Integer 0 - 65535
5 CH5 Value Unsigned Integer 0 - 65535
6 CH6 Value Unsigned Integer 0 - 65535
7 CH7 Value Unsigned Integer 0 - 65535
8 CH8 Value Unsigned Integer 0 - 65535

Example:

To read CH2, CH3 and CH4's real-time values, a Modbus master device sends in the following command:

Data(HEX) Description Note
0001 Transaction identifier Fixed 2-byte value
0000 Protocol identifier Fixed 2-byte value
0006 Length(6 bytes are followed) 2-byte value
01 The device address 1-byte value, don't care
04 Function Code (read Input Register) 1-byte value
0002 First register's address 2-byte value
0003 The number of required registers (read 3 registers 0002 to 0004) 2-byte value

Holding Registers:

A Holding Register stores a 16-bit integer indicating a setting for the data logger. To read one or more 16-bit Holding Register data, use function code 3.

Register Description Type Range/Equation
0 Sample Interval 0: below 1 second
>=1: sample interval in second
0 - 65535 seconds
1 Device Operating Mode 0: logging stopped
1: logger is logging data
 
10 CH0 Type 0:thermistor  
11 CH0 Enabled 0:disabled
1:enabled
If a channel is disabled, the reading is unknown
12 CH0 Equation 0: thermistor Range: -40 to + 70 ℃ / -40 to 158 ℉
Equation for Metrics:
O = 110 * I / 65535 - 40
Equation for Imperial:
O = 198 * I / 65535 - 40
X0 CHX-1 Type 0: Wide Range -8 to + 74 mV
1: Narrow Range -2 to + 18 mV
X1 CHX-1 Enabled 0: Disabled
1: Enabled
If a channel is disabled the reading is unknown
X2 CHX-1 Equation 0: Wide-Range Voltage Voltage Equation (mV)
O = 81 * I / 65535 - 8
1: Wide-Range TC E -171 to + 955 ℃ / -275.8 to + 1751 ℉
Temperature Equation (Metrics):
O = 1126 * I / 65535 – 171
Temperature Equation (Imperial):
O = 2026.8 * I / 65535 – 275.8
2: Wide-Range TC J -205 to + 1200 ℃ / -337 to + 2192 ℉
Temperature Equation (Metrics):
O = 1405 * I / 65535 – 205
Temperature Equation (Imperial):
O = 2529 * I / 65535 - 337
3: Wide-Range TC K -270 to + 1372 ℃ / -454 to + 2501.6 ℉
Temperature Equation (Metrics):
O = 1642 * I / 65535 -270
Temperature Equation (Imperial):
O = 2955.6 * I / 65535 – 454
4: Wide-Range TC N -270 to 1300 °C / -454 to 2372 ℉
Temperature Equation (Metrics):
O = 1570 * I / 65535 - 270
Temperature Equation (Imperial):
O = 2826 * I / 65535 - 454
5: Wide-Range TC T -270 to + 400 °C / -454 to +752 ℉
Temperature Equation (Metrics):
O = 670 * I / 65535 - 270
Temperature Equation (Imperial):
O = 1206 * I / 65535 - 454
6: Narrow-Range Voltage Voltage Equation (mV):
O = 20 * I / 65535 – 2
7: Narrow-Range TC E -35 to + 260 °C / -31 to +500 ℉
Temperature Equation (Metrics):
O = 295 * I / 65535 - 35
Temperature Equation (Imperial):
O = 531 * I / 65535 - 31
8: Narrow-Range TC J -40 to +330 °C / -40 to +626 ℉
Temperature Equation (Metrics):
O = 370 * I / 65535 -40
Temperature Equation (Imperial):
O = 666 * I / 65535 - 40
9: Narrow-Range TC K -53 to +437 °C / -63.4 to +818.6 ℉
Temperature Equation (Metrics):
O = 490 * I / 65535 - 53

Temperature Equation (Imperial):
O = 882 * I / 65535 - 63.4
10: Narrow-Range TC N -81 to +532 °C / -113.8 to +989.6 ℉
Temperature Equation (Metrics):
O = 613 * I / 65535 - 81

Temperature Equation (Imperial):
O = 1103.4 * I / 65535 - 113.8
11: Narrow-Range TC T -55 to +353 °C / -67 to +667.4 ℉
Temperature Equation (Metrics):
O = 408 * I / 65535 - 55
Temperature Equation (Imperial):
O = 734.4 * I / 65535 - 67
12: Narrow-Range TC B 0 to 1820 °C / 32 to +3308 ℉
Temperature Equation (Metrics):
O = 1820 * I / 65535
Temperature Equation (Imperial):
O = 3276 * I / 65535 + 32
13: Narrow-Range TC R -50 to +1539 °C / -58 to 2802.2 ℉
Temperature Equation (Metrics):
O = 1589 * I / 65535 - 50
Temperature Equation (Imperial):
O = 2860.2 * I / 65535 - 58
14: Narrow-Range TC S -50 to +1704 °C / -58 to 3099.2 ℉
Temperature Equation (Metrics):
O = 1754 * I / 65535 - 50
Temperature Equation (Imperial):
O = 3157.2 * I / 65535 - 58
15: Linear O = (LRH – LRL) * I / 65535 + LRL
Where:
LRH is Linear Range high value
LRL is Linear Range low value
You can get those values from SiteView
16: Wide-Range TC C 0 to 2320 °C / 32 to 4208 ℉
Temperature Equation (Metrics):
O = 2320 * I / 65535
Temperature Equation (Imperial):
O = 4176 * I / 65535 + 32
17: Narrow-Range TC C 0 to 986 °C / 32 to 1806.8 ℉
Temperature Equation (Metrics):
O = 986 * I / 65535
Temperature Equation (Imperial):
O = 1774.8 * I / 65535 + 32

Where X = 2,3,4,5,6,7,8,9
O = Output, I = Input Register Value

Example:

To read CH3's equation, a Modbus master device sends in the following command:

Data(HEX) Description Note
0001 Transaction identifier Fixed 2-byte value
0000 Protocol identifier Fixed 2-byte value
0006 Length(6 bytes are followed) 2-byte value
01 The device address 1-byte value, don't care
03 Function Code (read Holding Register) 1-byte value
002A First register's address (42 is 2A in HEX) 2-byte value
0001 The number of required registers (read 1 registers 002A) 2-byte value

Note:

  1. Modbus feature was added to firmware version 2.06 or above.

    To upgrade a data logger's firmware please refer to this link: How can I upgrade logger firmware?

  2. The age of an Input Register data is based on the Modbus request rate.

    A request of Input Register data will initiate the sampling process and the new data will be available upon the next request.

  • $688.00(USD)

Tags: PL-TW, wifi data logger, thermocouple data logger, temperature datalogger