Some AA batteries have different sized positive (+) terminals depending on their manufacturer. Batteries with a smaller positive terminal may not work after insertion.
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If this is the case, the positive connector on the ActivExpression2 device can be adjusted. Use a very small flat-blade screwdriver or other sharp, pointed instrument to gently prise forward the curved part of the positive connector.
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The next image shows the adjusted positive connector which has been moved slightly forward, compared to the other connectors which have not been adjusted.
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Once you have adjusted all three positive connectors, insert the replacement batteries.
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The batteries should now make contact with the positive connector. You may notice a small gap between the battery and the plastic housing. This is normal.

Replace the battery cover and tighten the screw. Power on the ActivExpression2 device.

Should you require any further assistance, please contact Promethean Technical Customer Support.