[BillA]

as has been previously discussed by many,
the measurement connections to the DUT have their own 'losses' and these need to be quantified in order that the gross readings may be corrected to arrive at a net value for the particular DUT parameter

some preliminary data was described in the thread on "C", this has been redone and expanded
for these tests the inst crosses, RTD ends, and connecting tubing were insulated with 3/8" closed cell neoprene

the hydraulic data is straightforward and the effect of temperature can be seen,
though not really in the flow range of significance - below 1.5 gpm - with the instrumentation used

of greater interest to me was the temperature data taken at the same time:
the ambient temp was held at 25°C and the dT measured at 11.5, 5.5, and 0°C temperature difference; then run again at 15.3°C with 0°C difference

there is a temp change w/o any DUT, for higher accuracy this must be addressed

the WCing testing community might consider the use of these (cheap) crosses as a de-facto std, everyone would have the same corrections
(there is an inst offset included in these curves which could be backed out)