What is dampening (in the dial trim choices)?
Perma-Cal® dampens pointer flutter by a unique technique. Dampening is recommended on all gauges except those used where ambient temperatures will fall below -5F (-20C). Our method of dampening, and the direct drive technology, eliminate the need for liquid fill. Q: What is a direct drive gauge? A: Direct drive refers to the bourdon tube (elastic element) being attached directly to the pointer, with no amplification method (gears, etc.) present. The Perma-Cal® triple layer helical-wound bourdon tube directly attaches to the pointer shaft, and due to its configuration, traverses the full arc of the scale. This provides a very linear reading gauge that maintains its accuracy because no gears or linkages, which tend to wear and fail, are used. Q: Can Perma-Cal® provide 0-100 inches of water column? A: 100 inches of water is equal to approximately 3.61 psi. The limits of the direct drive technology prevent us from providing a 270 arc on any pressure lower than 30 psi or its equ
