Fluke 52 User Manual

Page of 28
51, 52, 53, 54 Series II
Service Manual
6
52
51
54
53
zb03f.eps
Figure 1. Display Segments
Keypad Test
Check that all keypad switches are functional by pressing each key and confirming the
proper response on the display.
Wide Range Performance Test Procedure
This test verifies the instrument specifications. If the instrument fails this test, perform
the calibration procedure. If the unit continues to fail, it should be taken to a Fluke
service center.
Ice Bath Construction
To begin the performance test, first construct an ice bath as follows:
1.
 
Prepare a Dewar Flask by drilling two holes in its cap to accept the Mercury
thermometer and thermocouple wires, or use a standard laboratory cork.
2.
 
Fill the Dewar Flask with shaved or crushed ice made from distilled water.
3.
 
Fill the Dewar Flask with enough distilled water so that the ice turns to slush, but do
not add enough water to float the ice.
Note
As the ice melts, siphon off the excess water and add more ice. Allow
approximately 5 to 10 minutes for the water to drop back to the freezing
point.