Thermo Scientific CRYO Plus 1 Operating And Maintenance Manual page 16

Installation
Verification (cont.)
Thermo Scientific
Dip Level Test
This test compares the liquid level shown on the bar graph with the
actual level in the tank, using the ruler supplied with the unit. With the
tank filled and stable, lower the ruler along the edge of the tank until it
is at the bottom. (Take subsequent measurements at this same location.)
When the LN stops boiling, pull out the ruler. The actual liquid level
2
will be approximately one inch lower than the frost line on the ruler.
Compare this with the level shown on the bar graph. Measuring toler-
ance for the low scale (2" to 7") is ±1/2 inch. Measuring tolerance for
the high scale (1" to 25") is ±1 inch.
Caution Some shrinkage of the ruler may occur, depending on the level of
liquid nitrogen in the tank. ▲
Section 1
Quick Start-Up
7007400 Cryoplus 1-9