Howard HI-102 Overhead Transformer - Manual (Page 23)

Document 2.4.95, Revision 0
May, 2013
23
Fluid-Filled Overhead Distribution Transformers
if provided. Be aware that fluid temperature and
orientation of the transformer tank will cause
the fluid level to vary. Transformers are filled to
a level that corresponds to a fluid temperature
of 25°C. The actual fluid level will increase with
increasing temperature. The fluid level indication
will also vary when the transformer is not
installed in a level orientation. If the fluid level is
low, add fluid according to the instructions in the
“Filling with Fluid” section.
10. Check the torque values on all electrical
connections, including ground connections,
and tighten as necessary. Refer to the torque
guidelines contained in Tables 1 through 4.
11. Replace any damaged or unreadable
nameplates, instructional labels, and safety
labels.
12. If it is suspected that water or other
contaminants may have entered the tank, the
fluid should be tested to determine its condition.
For transformers filled with conventional
transformer oil, Refer to IEEE Standard C57.106,
"Guide for Acceptance and Maintenance of
"Insulating Oil in Equipment." For transformers
filled with less-flammable high molecular
weight hydrocarbon insulating fluid (such as
R-Temp), refer to IEEE Standard C57.212,
"Guide for Acceptance and Maintenance
of Less Flammable Hydrocarbon Fluids in
Transformers." For transformers filled with seed-
based fluids (such as Envirotemp FR3 ™ ) refer to
IEEE Standard C57.147, "Guide for Acceptance
and Maintenance of Natural Ester Fluids in
Transformers" for information. For transformers
filled with silicone fluid, contact the Howard
Industries Transformer Division for information.
Electrical Tests
The following electrical tests can be used to
determine the condition of the transformer. Comply
with instructions and precautions provided by
the test equipment manufacturer. Contact the
Howard Industries Transformer Division for further
information.
▲
! DANGER
FAILURE TO FOLLOW THE INSTRUCTIONS
BELOW WILL RESULT IN DEATH OR SERIOUS
PERSONAL INJURY, AND COULD ALSO RESULT
IN DAMAGE TO THE EQUIPMENT .
Be aware of dangerous voltages and avoid
personal contact with live terminals.
▲
! WARNING
FAILURE TO FOLLOW THE INSTRUCTIONS
BELOW COULD RESULT IN DEATH OR SERIOUS
PERSONAL INJURY, AND COULD ALSO RESULT
IN DAMAGE TO THE EQUIPMENT.
• De-energize the transformer and ground all
transformer terminals.
• Only qualified personnel with appropriate
equipment should perform these tests.
• Wear personal protective equipment (PPE)
to prevent injury from potential arc flash or
contact with dangerous voltages.
• Make sure the transformer tank is properly
grounded at all times.
• After testing is complete and the transformer
has been reconnected to the line leads,
energize the transformer from a remote
location.
1. Insulation Resistance Test—Refer to “Insulation
Resistance Test” for instructions.
2. Ratio Test—Refer to “Ratio Test” for instructions.
3. Insulation Power Factor Test—Refer to “Insulation
Power Factor Test” for instructions.
4. Fluid Quality Tests—Moisture content, power
factor, dielectric strength and dissolved gas
analysis.
Exterior Paint Finish
Any damage to the exterior paint finish that exposes
the primer coat or bare metal should be repaired
immediately in order to prevent corrosion. Areas
to be repaired should be thoroughly clean and dry.
The surface should be sanded to remove rust, loose