Single Channel Displacement / Crack meter Transducer Interface

Features

Support for 120 to 10 K Ohm Displacement transducers or crack meter.

Full bridge Operation

Precision Temperature Sensor
User Programmable Configuration
SDI-12 / RS-485 Digital Communication Option
Extended SDI-12 Address Support: 0-9 , a-z
16 Bit Precision Low Noise ADC
Low Power - minimal self heating effect - sensor only switched on during acquisition operation.

Engineering and raw data values

Fully integrated into the Q-LOG Data Recording Software

Power Supply

10 -18 V

Current

1 mA at acquisition
10 uA standby

Comms Port

Options for
SDI-12 Port
RS-485 Port

Max update rate

1 sec

Cable Clamp Size

2 mm diameter

Sensor Excitation

3.3V standard
Other range on request

Resolution

Range / 65536

Raw Value

Raw data mV/V

Engineering Value

m , cm, mm,
User defined

Range

User defined, depends on sensor installed

Temp Sensor

Thermistor

Thermistor Type

10K 3A1 Betatherm

Calibration

User defined scalable parameters

Accuracy

0.05 Deg
-8 to 25 Deg C

Range

-30 to + 60 Deg

Units

Deg C / Deg F
user select

PCB Dimension

Length

60 mm

Width

19.7 mm

Max depth

11.2 mm

Number Channels

Gauge Resistance

120 - 1K Ohm

Gauge Factor

User Defined

ADC

16 Bit

Statistics

Strain

Max, Min

Temp

Max, Min

Single Channel Displacement / Crack Meter Interface

For the AquaLOG Data Recording Instrumentation

Supports SDI-12 or RS-485 digital communications

Geotechnical Services

Part Number: NP-Crack-v1-G1

SDI-12 Comms
Port

The image opposite shows both the NP-Crack-v1 circuit board and its plastic waterproof housing. The housing protects the device from the ingress of moisture and dust.

The PCB can be customised to be directly installed into sensor housings. This gives 3rd party devices a simple upgrade path to connect to data loggers, SCADA and acquisition system.

No programming knowledge required to use this device.

Dimensions ( mm )

Length

Diameter

Cable Gland Entry

3 - 6

Gland rating

IP 65

Housing

Sample Commands

The following command can be used to test the NP-Crack-v1 sensor. SDI-12 / 485 address is 0.

[D] 0M! 0D0!

Select Image to download
data sheet

Introduction

The NP-Crack-v1 is an intelligent general purpose interface suitable for direct connection to resistive displacement transducers or crack meter. The device connects to any suitable logger supports SDI-12 or RS-485 digital communications.

The product is available as a stand-alone PCB for inclusion for OEM applications, or as a complete sensor with a sealed waterproof enclosure.

Advantages:

Digital data transmission - no errors due to signal losses in cable.
Ensemble average measurements - 50 / 60 Hz mains noise rejection
Measurements in Engineering Units / Raw (mV) - User Selectable
Local temperature measurements for thermal compensation Fast Simple Installation - Add or remove sensors when required.

Part Numbers

Description

NP-Crack-v1-H-SDI12

Half Bridge with SDI-12 Comms

NP-Crack-v1-F-485

Full Bridge with RS-485 Comms

Additional Statistics can be added for OEM Clients

The NP-Crack-v1 range of cards supports full User configuration, ensemble averaged measurements for enhance noise rejection and signal/noise enhancement. The measurements can be converted direct to engineering units. This device can be connected to any 3rd party logger or data acquisition system supporting SDI-12 or 485 digital communications.

Free application software for up-to 10 sensors
per network.