Charge Decay Test Unit JCI 155
For assessing the electrostatic suitability of materials by measurement of charge decay and capacitance loading characteristics. The design of the JCI 155v5 instrument satisfies the requirements of BS 7506: Part 2: 1996 and IEC 61340-2-1.
The JCI 155v5 uses a high voltage corona discharge to put a localised patch of charge on the surface to be tested with a fast response 'field mill' fieldmeter to measure, without contact, the initial peak voltage created by the deposited charge and how quickly the surface voltage falls as this charge migrates away. Measurements of the quantity of corona charge transferred, made with a JCI 176 operating in conjunction with the JCI 155v5, allow direct assessment of the 'capacitance loading' experienced by the deposited charge. Temperature and humidity conditions within the instrument are recorded for each test run. The special feature of the new JCI 155v5 instrument is that it includes an integral microprocessor so that all basic analysis, display and storage of charge decay curves is carried out by software within the instrument. The aim is to make normal instrument use very easy, but to have a wide range of options available for adjustment of test and analysis conditions when needed.
Observations are stored to a PCMCIA or CompactFlash memory card slotted directly into the instrument. The stored data can be transferred into a microcomputer running software JCI-Graph in Windows 95/98/2000/XP. This proprietary software provides for direct remote initiation of instrument operation with display of charge decay graphs and automatic calculation of capacitance loading values. The software also provides for off-line analysis and display of results and for long term secure data storage. It generates a Spreadsheet table summarising test conditions and results obtained with the option to create .csv files from observations.
Decay times can be measured from below 50ms up to millions of seconds and with initial peak surface voltages from below 50V up to about 3kV. Opportunity is provided for slow plate release to minimise air disturbance when studying fine powders. Operation by integral 600mAh battery (over 4 hours) and by 115V/240V mains supply.
Supplied in carrying case with mains lead and software disc JCI-Graph and with instrument and software User Manuals.
