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ENAMEL RATER MANUAL: V.10
The 'Rating', 'Low Level' and 'Contact Fault' indicators
should be lit and the milliamp display should show the
reading given in the table below for the rating voltage in
use:
RATING
VOLTAGE
MILLIAMP DISPLAY READING
4
4+0.2mA
6.3
6.3+0.2mA
10
10+0.3mA
12
12+0.4mA
15
15+0.5mA
If this is not the case first check that the crocodile clips
are making good contact. If this does not cure the fault
refer to section 5.5 'Fault Finding'.
v.
Repeat the test in reverse polarity.
Now the 'Low Level' and 'Contact Fault' indicators should
be off and the 'Reverse Polarity' and rating indicators
should be lit. The milliamp reading should be the same.
Note:
This test is far superior to internal calibration tests as it
will detect the more likely faults such as corroded or dirty
connectors and damaged probe cables. It will not,
however, show up equal and opposite drift of internal
voltage and current references. This test should therefore
be supplemented with calibration against a good quality
external meter as detailed in section 5.4.
