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Old 02-23-2004, 02:46 PM
sbourg sbourg is offline
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Join Date: Jul 2001
Location: SoCal
Posts: 1,303
The pump is bi-directional. It provides positive pressure in one direction, negative (vacuum) in the other. It needs not only 12V to run, but also information as to which direction. The sense leads are touched momentarily (1-2 sec) to either 12V or ground to choose the direction. An internal flow/pressure switch turns it back off.

Steve
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