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[IonCube]

@ http://www.emersonpr...perts.com/2011/05/eliminating-temperature-effects-in-dp-level-measurement

 

In the above article I cannot comprehend two sentences & I request clarification

Temperature effect has two components-seal temperature effect and head temperature effect. Seal temperature effect is caused by the backpressure generated on the sensing diaphragm when the ambient temperature changes. This causes an expansion / contraction of the fill fluid in the capillary. Head temperature effect is caused by changes in the weight of the capillary fill fluid due to density variation with varying ambient temperatures exerting backpressure on the sensing diaphragm.

 

How are the effects classified as two?

if the temperature rises liquid expands (whereby its density is lowered) so the rise in any liquid level is compensated by a reduced density... so isn't the two effects cancel out each other. I doubt any backpressure because of this 'seal' effect

Traditionally, it was believed that the same length capillary would offset the temperature effect in the capillaries. However, it only offsets the seal temperature effect and still leaves behind the head temperature effect.

 

I really can't understand this. Willn't the density be lowered if the liquid expands