CSZ NORM-O-TEP 111Z, Руководство по эксплуатации и техническому обслуживанию

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Operation / Technical Manual NORM-O-TEMP, Model 111Z
Page 62 of 81
6-16. Electrical Safety
The NORM-O-TEMP
®
unit should be checked quarterly for electrical safety.
It is appropriate to perform such inspection upon receipt of a new unit prior to
acceptance, following repair and/or service of the unit, and then again during each
periodic inspection.
6-16.1. Ground Integrity
Ground path resistance must be less than 0.2 ohms.
Using a Digital Multimeter or equivalent, verify resistance between the following
test points:
1. between any exposed, unpainted part of the metal case of the NORM-O-
TEMP ® and the ground conductor of the power plug,
2. between the ground conductor and the quick-disconnect fittings, and
3. between the ground conductor and the handle.
If a NORM-O-TEMP
®
unit has ground path resistance that exceeds the
appropriate limit, the cause should be investigated and corrected prior to
returning the unit to active service.
6-16.2. Leakage Current
Leakage current must be less than 300 microamps.
Using a Safety Analyzer, verify leakage current under the following conditions
first while the unit is
grounded
and then again when the unit is
ungrounded
:
1. Power
ON
, polarity normal and then polarity reverse. When measuring in
these conditions, measure when the NORM-O-TEMP
®
unit is heating and
circulating water (both the heater and pump are ON).
2. Power
OFF
, polarity normal and then polarity reverse. When measuring
in these conditions, measure when the NORM-O-TEMP ® unit is going
through self-calibration. This is when it is first turned on (both the heater
and pump are OFF).
If a NORM-O-TEMP
®
unit has leakage current that exceeds the appropriate limit
or has a significant increase in leakage current, the cause should be investigated
and corrected prior to returning the unit to active service.
Excessive leakage current is most commonly caused by a defective heater, but
other components can also fail in such a way as to increase leakage current. To
find the source of excessive leakage current, suspect components should be
sequentially disconnected until the source of the high leakage current is isolated.