PL-VW PRECISE-LOG Voltage Data Logger
PL-VW is an 8-channel, battery powered, standalone and WIFI-enabled voltage data logger. The logger records eight external voltage sources and saves data in 8-MB memory.
Its aluminum enclosure makes it excellent in the harshest industrial environment.
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.
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
- 8 megabyte memory size
- Both USB and WIFI comm. interfaces with baud rate of 115200 bps
- Programmable input ranges (5 VDC, 20 VDC)
- Support Modbus TCP protocol
- Over 10 years of battery life
- Powerful software for configuration, downloading, plotting, analysis and alarm reporting
- Wide sampling interval selections (one second to 12 hours)
- Rugged aluminum enclosure
Documents:
PRECISE-LOG Voltage Data Logger Specifications
How to configure WIFI settings
General | |
---|---|
Product Name | PRECISE-LOG Voltage Data Logger |
Model | PL-VW |
Inputs | |
Connection | Plugable terminal block for eight external channels |
Channels | Eight external voltage DC. Programmable input selections for each external channel: 0 ~ 20 VDC 0 ~ 5 VDC |
Resolution | 0.0018% |
Accuracy | ±0.05% FSR @ 25 °C |
Input Impedance | > 1 MOhms |
Over-Voltage Protection | Up to ± 40 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 |
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-VW 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 |
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 |
|
X0 | CHX-1 Type | 0: Range#0 (0 to 20 VDC) 1: Range#1 (0 to 5 VDC) 2: Range#2 (-5 to +5 VDC) |
|
X1 | CHX-1 Enabled | 0:disabled 1:enabled |
If a channel is disabled, the reading is unknown |
X2 | CHX-1 Equation | 0: Range#0 Voltage | Range: 0 to 20 VDC Equation O = 20 * I / 65535 |
1: Range#1 Voltage | Range: 0 to 5 VDC Equation: O = 5 * I / 65535 |
||
2: Range#2 Voltage | Range: -5 to +5 VDC Equation: O = 10 * I / 65535 – 5 |
||
3: 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 |
Where X = 1,2,3,4,5,6,7,8
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:
- 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?
- 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.