Re-design of the electrical setup of a mixing station in an Ex area

 

(Anonymized customer story from a chemical plant).

 

Need for a re-design of a mixing station’s electrical setup

In 2014 a member of the maintenance team at the facility decided to re-design the electrical setup of a mixing station located in an Ex-area. The station is used for test production and simulation as well as for training purposes.

 

The goal was to get a more flexible setup adding local easy-to-read indication and fast programming to temperature converters connected to the sensors monitoring the pumps and mixers without compromising on the accuracy and robustness of the device.

 

 

Easy-to-install and easy-to-program solution

For this application the maintenance team needed a temperature converter that was easy to install and program on-site; solved by using the detachable PR 4501 display that can be snapped onto the front of the device.

 

The finished installation consisted of twenty-five PR 9113B converters mounted on DIN rail and power rail and twenty-five PR 4501 detachable displays. The PR 9113B and the display is SIL 2 certified and fully assessed according to IEC 61508.

 

The solution is simple and yet flexible as the modules can be easily be installed on it or removed from it – a solution that is safe to work with. With the display on the front of the devices, maintenance staff can read the sensor data, see if a sensor is not performing as expected, configure the converters, and much more.  

 

 

The installed PR 9113B temperature / mA converters to the right.

 

The new setup has performed as expected and has made it possible to work safely with the installation on-site instead of remotely from a PC.

 

 

Application:

 

 

 

Easy and accurate calibration

The PR 9113B Temperature / mA converter offers easy and accurate calibration on-site using the 4501 programming front – i.e. without using any external calibrators or a PC.

The device can be process-calibrated at 2 points to fit a given input signal. A low input signal (not necessarily 0%) is applied and the actual value is entered. Then a high signal (not necessarily 100%) is applied and the actual value is entered. When the user chooses to use the calibration, the device will work according to this new adjustment.  

 

If the user later rejects this menu point or chooses another type of input signal the device will return to factory calibration.

 

The user can also save the calibration for backup purposes using the PR 4590 ConfigMate which can operate as a docking station for the 4501 programming front - allowing the 4501 to be connected to a PC and the PR PReset software. Once saved to a PC the calibration settings can be printed as well. 

 

 

 

The 4501 calibration menu. 

 

Faster calibration with the new set-up

After the installation the maintenance team noticed that using the 4501 detachable displays when calibrating saved them a considerable amount of time compared to the previous set-up and 'old' way to calibrate.