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Depth – Water Level Bubbler

Water Level Bubbler

The PR-7200 is a complete water level bubbler system for measuring the depth of water.

An air tube runs from the PR-7200’s compact compressor to the water, where the tube is submerged. This allows the PR-7200 to be sited safely away from the water, meaning only replaceable tubing can be damaged.

Based on the advanced liquid level sensor of the PR-6100, the PR-7200 provides a measurement of the attached capillary tube pressure, conversion, output to recorders and controllers and control over the PR-7200 integrated compressor module.

Greenspan PR-7200 water level bubbler system

Serial or Analogue Ouput?

The PR-7200 series can have either an analogue output or an integrated logger with serial output. It is possible to have both options simultaneously.

PR-7200 Buble system in action

PR-7200 Operating Principal

When a measurement is activated by a preset command or by an external controller (logger, PLC, RTU etc.), a measurement sequence begins. The compressor runs for several seconds only and charges the capillary tube with a high flow purge. A dwell interval then allows the tube pressure to equalize with hydrostatic pressure for a set time period. After this, pressure measurement is taken, processed and displayed or output to the controller.

Australian Made

Greenspan has made our range of water quality sensors in Australia for over two decades. Our experience has allowed us to design sensors that reliably deliver accurate data in the harshest environments Australia has to offer.

With every Greenspan water quality sensor, you receive; local support from our experienced sales and service technicians, local repairs and recalibration from our Melbourne-based engineers, and access to local spares from our factory in Melbourne. No other brand of water quality sensor can offer such exceptional service.




PR-7200 Specifications

Measurement TechniqueRemote Pressure Bubble System
Range10, 20, 35, 70 meters freshwater (15, 30, 50 and 100psi) -non standard ranges are available
AccuracyDigital output (Display, RS232, SDI-12):
Linearity: +/-0.05% of FS
Temperature: +/-0.001% per °C
Repeatability: +/-0.01% of FS
Long term drift: <0.05% of FS/year
Analogue output: +/-0.15% over 0°C to + 50°C
UnitskPa, psi, feet, inches, meters, centimeters, flow and volume units based on above
Resolution Analogue: 12 bit
Digital: 16 bit
Display m – 3 D.P. (eg. 2.345m)
mm – 0 D.P. (eg. 2345mm)
ft – 2 D.P. (eg. 7.69ft)
in – 1 D.P. (eg. 92.3in)
p.s.i. – 3 D.P.(eg. 3.518psi)
kPa – 3 D.P.(eg. 5.025kPa)
TemperatureOperating range: -10°C to 60°C
Response Time30 seconds (default) measurement sequence from standby
Immediate if using Continuous Run Mode
TypePiezo resistive differential pressure sensor (one side vented to atmosphere)
Output optionsAnalogue: 4-20mA current, 3 wire loop (up to 450 ohm load @12Vdc)
Digital: SDI-12 data protocol version 1.3 RS232C data
Simultaneous digital and analogue output
Tube connection¼“ tube brass fitting with 3/8” tube adapter standard with a selection of other tube fittings available
Power supply12Vdc, 16A compressor supply –
use battery and charger.
PR-7100 sensor uses same supply
Standby @12V: <10 mA
Active @12V: <120mA backlight on* <25mA backlight off* *plus current loop if used
Surge protectionInputs/ outputs protected against Transients by a secondary protection circuit that can absorb up to 1.5kW for 1ms
EnclosureIP67 rated
Display4 line x 20 character LCD (7 x 5 dot matrix) with backlight, extended temperature range
Weight4.2kg PR-7200 only
5.3kg shipping weight

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