Dry-Out - HPS EnduraCoil 1.2 KV Manual De Instrucciones

Installation Precautions (continued)
FORKLIFT TUBES
ANTIVIBRATION
WITH 4 WAY
PADS INSTALLED
SKIDDING
BY HPS
FIGURE 11

Dry-Out

DANGER
HAZARD OF ELECTRIC SHOCK, EXPLOSION,
OR ARC FLASH
Failure to observe these dry-out procedures
will result in death or severe personal injury, or
considerable property damage.
Installation, Operation, and Maintenance Guide - Cast Resin Transformers
7. If any drilling, grinding or painting needs to be done, the
core and coil assembly must be protected by a cover sheet
(e.g. Tarp) so that nothing can land on or inside the coil.
8. Do not replace brass bolts with other material bolts.
JACKING LOCATIONS ON
EITHER SIDE OF BOTTOM
CHANNELS
If a transformer has been exposed to moisture such as
condensation or rain, or stored in a high humidity environment,
the transformer must be dried out prior to energization. If
the transformer has been accidentally exposed to excessive
moisture, immediately remove the transformer from service.
Perform Megger tests (Insulation Resistance Test) at intervals
to indicate a change is taking place with the moisture content
in the insulation. Then proceed with the following dry-out
methods:
1. Surface moisture should be blown or wiped off any surface
of the transformer to reduce the time of the dry-out
period.
2. Direct external forced heated air, or radiant heat, up
through the windings with all the ventilation openings
cleared. Recommended temperature should not exceed
105°C (221°F). Continue this for a minimum of 24 hours
or until all evidence of moisture or condensation is no
longer visible.
3. Electric heaters could be installed inside the enclosure -
particularly for transformers stored outdoors. These heaters
should be located under the windings on both sides of
the core. If heaters are used, air circulation through the
enclosure must be permitted. Fiberglass furnace filters
may be mounted temporarily over the inlet and outlet
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