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Battery warning device
12th November 1971, Page 134
12th November 1971
Page 134
Page 134, 12th November 1971
— Battery warning device
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Applied to car batteries in March of this year, the Levelite signal light has been developed by NSA for commercial vehicle batteries to give a visual warning of low electrolyte level. Built into each of the vent plugs, the device comprises a prism-ended plastics probe, and operates on the refracted-light principle. If the end of a probe is below the level of the solution there is no light refraction, but when the prism is exposed by a fall in the level below the probe, light passes up the stem to illuminate a small circular disc on the top. It has the effect of switching on a light in the vent plug.
Made by: NSA Ltd, Lomond Works, Blackwater Way, Aldershot, Hants.