The Purex 400i features fully automatic function; all the user has to do is set the appropriate airflow on installation. It has a dedicated control, monitor, and display system unique to Purex fume extractors. Purex filter monitor units are in all our digital units; which is highly recommended for gases and chemicals.
Purex 400i Components
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Control System
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Switching the machine ON/OFF
To switch the machine ON press the central button on the keypad. The central button will illuminate (green) and the motor run indicator on the graphic display will rotate.
Pressing the central button again will switch the machine OFF, extinguish the green light and the motor run indicator on the graphic display will stop rotating.
Adjusting the airflow rate
To adjust the airflow rate, press the UP and DOWN buttons together. Both buttons will then begin to flash (red). To increase the airflow rate, press the UP button, to decrease the airflow rate press the DOWN button.
The target airflow measurement is shown on the graphic display together with the actual airflow being achieved by the fume extractor. Once the target value has been set, do not touch any other buttons. After a few seconds, the buttons will cease to flash, and the set value will be stored.
What airflow rate to set?
For most applications, a good starting point is a flow rate of 50% of the machines maximum capability. Check the fumes are being removed by site observation and appropriate measurement. Then increase or decrease the flow rate as appropriate. Please note that setting the flow level unnecessarily high may reduce filter life.
Fully automatic operation
The airflow rate is the only parameter that needs to be set by the operator. The Purex machine will automatically maintain the airflow level you have set without any further intervention required.
Graphic Display
The graphic display shows the operating status of the machine in one easy glace.
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Filter Fault Indicators Note
Some machines use a single combined particle / chemical filter while others employ separate chemical and particle filters. Therefore, the machine icons and filter positions (see 5,6,7) may vary depending on the type of machine you have.
Filter Status (1,2,3)
Purex Digital machines warn the operator if the chemical filter is saturated, or the particle filter is blocked. Sensors are also used to warn the operator if particles or gas are passing through the machine into the workplace due to a missing, damaged, or incorrectly fitted filter.
When gas or particles are sensed or the filter is nearly saturated/blocked, the machine will warn the operator with an audible chime and the keypad will flash (red).
At this point the appropriate filter icon (see 5,6,7) will flash to show which filters may need attention.
Exhaust Temperature (4)
when the machine temperature rises above a preset limit the machine will warn the operator with an audible chime every 20 seconds and the keypad will flash (red) every 10 seconds. This feature allows the operator time to identify the problem. If the problem continues then the machine will chime and the keypad will flash (red) every 1 second. See problem solving section.
Motor Run Indicator (8)
This icon will rotate when the motor is running.
Target Airflow / Actual Airflow (9,10)
The operator can set the target airflow to the level they require, although in most cases this will be factory preset at the correct level. The Purex machine will automatically raise or lower the motor speed as required until the actual airflow rate equals the target airflow rate.