ESR (erythrocyte sedimentation rate).
That's odd ... I have seen a document on line that concludes that the Electa Lab Monitor 100 tends to underestimate the manual ESR readings. More research required!
Are you sure that the manual tests (presumably following the Westergren method) are producing reliable results?
As an aside, the Italian Electa Lab company has changed hands at least a couple of times; acquired by Clinical Data Inc. ... which was itself taken over by Forest Laboratories in the States. In turn Forest* was taken over by Actavis (now Allergan). It seems that the ESR instrument business is very ... er, transient.
* Famous for Sudocrem ... good for nappy rash!