LEO3 Current or Digital Output Pressure Gauge

LEO3 Current or Digital Output Pressure Gauge

LCD digital pressure gauge powered externally by a 2 wire series 4-20mA current loop or a digital interface.

Product Parameters

  • Pressure Range: from -1 to 3 bar up to 1000 bar gauge or absolute
  • Accuracy: +/-0.2% full scale over 0 to 50 Deg C
  • Display: 4 1/2 digit LCD
  • Output Signal: 4-20mA, 2 wire and RS485
  • Supply Voltage: 8-28 Vdc
  • Dimensions: 76mm x 125mm x 50mm
  • Weight: approx 210g
  • Environmental Protection: IP65
  • Pressure Connection: G1/4 male
  • Special Features: settable current loop output, RS485 digital interface, selectable pressure units
  • Special Options: Connect to a PC via RS232 or USB

Product Description

The LEO3 can be used a pressure transmitter or a digital output pressure sensor with a local readout display. Accurate to 0.2% FS the LEO3 is available in a selection of pressure ranges from -1 to 3 bar up to 1000 bar (-15 to 45 psi up to 15,000 psi).

The LEO 3 loop powered pressure gauge is externally protected to IP65 and a Binder 723 5 pin connector on the back of the case provides connection for the series loop or digital interface. The plastic case can be further protected from impact via an optional rubber protection boot cover.

Using the optional PC software the 4-20mA analogue output can be altered to a different scaling. Pressure readings can also be transmitted directly to a computer and recorded without the need to connect the 4-20mA current loop circuit.

Product Applications

Destructive testing

Destructive pressure testing up to 1000bar

  • SKU ID: s1-leo3-0006
  • Part No: 303015.0005 / 309010.0076
  • Pressure Range: 1000 bar sealed gauge
  • Output Signal: 4-20mA, 2 wire analog and RS485 digital
  • Accuracy: 0.1% FS at room temp, 0.2% FS including 0 to 50°C temp errors
  • Process Connection: G1/4 male
  • Optional Extras: USB data cable & PC logging software

Product Help

2 bar air presssure gauge, 4-20mA & logger

We want to measure and control air pressure and require a pressure gauge with a 4-20mA output which is externally powered, fitted with 1/4NPT thread, and a data logger would be an advantage.

4-20mA or PC logging

The logging function of the LEO3 can only be used if it is connected to a PC and you are not using the 4-20mA output at the same time.

The output can be configured to 0 to 2 bar gauge via the software & USB interface supplied with the LEO3, which is also used for datalogging.

  • SKU ID: s1-leo3-0004
  • Pressure Range: -1 to +3 bar gauge
  • Output Signal: 4-20mA, 2 wire analog and RS485 digital
  • Accuracy: 0.1% FS at room temp, 0.2% FS including 0 to 50°C temp errors
  • Process Connection: G1/4 male
  • Optional Extras: USB data cable & PC logging software

4-20mA & logging at the same time

This package will allow you to use the the 4-20mA and log the readings via the 4-20mA logging kit without the PC connected.

  • SKU ID: s1-leo3-0005
  • Pressure Range: -1 to +3 bar gauge
  • Output Signal: 4-20mA, 2 wire analog and RS485 digital
  • Accuracy: 0.1% FS at room temp, 0.2% FS including 0 to 50°C temp errors
  • Process Connection: G1/4 male
  • Optional Extras: USB data cable & PC logging software
  • Optional Extras: 4-20mA Transmitter Data Logging Kit

1 Hz min. sample rate for logging vacuum to -30kPa g

I want to measure vacuum pressure in a tube. The maximum vacuum expected is 30kPa, and I need software  to log at 1hz minimum sample rate, then transfer the data to a .txt file for post processing.

The LEO3 has a sample rate interval as low as 30 msec (33 Hz) and the accompanying software contains an application solely for converting the data file to a .txt format text file for opening in a spreadsheet program.

  • SKU ID: s1-leo3-0003
  • Part No: 303015.0001 / 309010.0076
  • Pressure Range: -1 to 3 bar sealed gauge/4 bar absolute
  • Accuracy: 0.2% full scale including 0 to 50 degC
  • Process Connection: G1/4 male
  • Digital Communication: USB data cable & software

Recovering LEO3 logging settings

I am using a LEO3 pressure sensor and the Control Center Series 30 software to record and log data on a leak testing station. The problem I am having now is that whenever the measurement window is closed, the settings reset. So next time we want to do a measurement, the operators have to come find me and I have to reset our parameters. Leaving the window open forever is not a realistic option. Is there any way to save the measurement settings?

If you are saving the measurement data, then it is possible to load the old measurement data and continual measuring by pressing start.

Extract from CCS30 manual page 15:

CCS30 saving loading adding measurements

Using Windows parameters to open LEO3 measurement files

How do you use the parameters explained on page 22 of the CCS30 manual?

CCS30 Parameters at program start

The parameters are defined for use in the windows shell, same as you would do with other programs under windows. Under Windows XP, the CCS30 is located under:

C:\Program Files\KELLER\ccs30\CCS30.exe

To open a File, you have to add the File-name with a space after CCS30.exe. Place the path in “…” if there are spaces in the path!

Example for opening a measurement file:

C:\Program Files\KELLER\ccs30\CCS30.exe "C:\Temp\meas 23.cc3"

Example of opening and running a measurement file:

 C:\Program Files\KELLER\ccs30\CCS30.exe -run"C:\Temp\meas 23.cc3"

Combined LEO3 RS485 & 4-20mA Outputs

Does the LEO3 always include a RS485 interface with the 4-20mA output?

Yes, the RS485 serial communications as always included along with the 4-20mA current loop output.  Both are accessed via the back entry Binder 723 connector.

LEO3 pin wiring

Missing calibration certificate

No calibration certificate was delivered with the LEO3, is it possible to obtain after delivery?

As standard no cal cert is produced for the LEO3, but the data is collected during manufacture and recorded.  If necessary it is possible to produce a retrospective calibration certificate using this data, and there will be an additional charge to supply this.

LEO3 5pt cal cert

Labview driver

Is it possible to create a Labview interface for the serial output of the LEO3 pressure gauge?

The Software package which comes with the USB or RS232 interface converter includes some example DLL drivers for past versions of Labview.

USB powered

Can the LEO3 pressure gauge be directly powered from the USB interface?

Yes the USB interface will provide enough power to activate the digital display enabling you to change display parameters via the front panel and configure the analogue output via the PC software provided with the USB converter cable. It is not possible to use the analogue output when using the LEO3 in this mode.

Recording multiple gauges simultaneously with Read30 software

Is the software that comes with the LEO3 digital output pressure gauge capable of recording multiple instruments? and if so, how many can be used at the same time? Also are these pressure gauges compatible with National Instruments LabVIEW software?

The Read30 software will accept up to 249 different device addresses and the software can be configured to log up to 16 measurement channels simultaneously.
Read30 software configuration for recording multiple channels
There are some sample drivers included on the provided software CD which were written for earlier versions of LabVIEW.

Reading up to 3 bar with a 10 bar overpressure limit

I’m interested in the LEO3 loop powered pressure gauge for measuring pressures up to 3 bar, but I need it to withstand pressure up to 8 bar max, I don’t need to read up to 8 bar but I need to leave it connected for greater pressures, will this be possible?

Since the optimum measurement range of the LEO3 for this application would be -1 to 3 bar, the overpressure limit will 10 bar, the gauge will not read up to 8 bar but it is designed to withstand this pressure without affecting measurement performance.

Gasoline compatibility

We are looking at possibly selecting the LEO3 digital output pressure gauge for connecting to a PC for use as a pressure datalogger on gasoline, could you advise whether it is compatible with gasoline and also whether it is intrinsically safe?

Although the LEO3 has stainless steel and Viton materials in contact with the pressure media it is not ATEX approved for intrinsic safety. As an alternative we would suggest you use a LEO Record Ei which is an ATEX approved pressure logger. The LEO Record Ei has the same process connection materials as the LEO3. You will be able to store results within the LEO Record inside the intrinsically safe zone and then upload results later via a communications cable in a safe area.

Computer readout for up to 10000 psi

I want to add a computer readout device to a conventional manual hydraulic shop press. The idea is to be able to measure compressive strength and be able to save the data for exporting to another program. It would be best if the device could read up to 10,000 pounds per square inch. Does the LEO3 work this way?

The LEO3 has a built in display and the ability to be connected to a computer where the supplied software can log continuously and save the data as a text file for exporting to other software applications.

The 700 bar range would be suitable for measuring over 0-10,000 psi and will display the pressure or save the readings in psi pressure units if selected.

Converting absolute range to read 0 to -1 bar

I have a technical query about how the LEO3 analogue output pressure gauge can measure from 0 to -1 bar since the product data sheet only mentions 0 to 4 bar absolute?

The 4 bar absolute range mentioned on the data sheet can be used as a -1 to 3 bar sealed gauge or a 4 bar absolute range. There is a zero offset button that can be selected from user interface menu list. This can be selected when the instrument is vented to atmosphere converting the displayed reading from measuring atmospheric pressure to zero pressure. If a negative pressure is applied to the pressure gauge it will now read a minus value. Since the sensor inside the gauge has a sealed reference, the zero setting should be checked on a regular basis, preferably each time the gauge is vented to atmosphere to ensure the most precise negative pressure reading.

-1 to +1 bar gas measurement

Is it possible to use the LEO3 to monitor gas pressure over the pressure range from -1 bar to 1 bar?

Yes, you can use a -1 to 3 bar gauge range to measure either -1 to + 1 bar gauge:

  • SKU ID: s1-leo3-0001
  • Pressure Range: -1 to 3 bar gauge
  • Accuracy: 0.2% full scale including 0 to 50 degC
  • Process Connection: G1/4 male
  • Digital Communication: USB data cable & software
  • Calibration Certificate: Traceable, 5 points

Negative & positive pressure

Can the LEO3 be used for both a gauge pressure and a negative gauge (vacuum)?

Yes, the best standard range would be a -1 to 3 bar version, which will measure both negative and positive pressure, or can also be switched to read absolute pressure as well.

Measuring & graphing vacuum

I want to measure vacuum and display graphing values over time in the range of 0 to 60 seconds from 0.01 to 0.22 bar (0.15 to 3.19 psi), and the gas is air?

  • SKU ID: s1-leo3-0002
  • Part No: 303015.0001 / 309010.0076
  • Pressure Range: -1 to 3 bar sealed gauge/4 bar absolute
  • Accuracy: 0.2% full scale including 0 to 50 degC
  • Process Connection: G1/4 male
  • Digital Communication: USB data cable & software
  • Calibration Certificate: Traceable, 5 points

Related Documents

Specification data sheet

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