Livestock Waterers - Safe
Installation in Cold Climates and
the Use of Electrically Heated
Waterers
Robert Fick Ph.D., PE
Senior Agricultural Engineer
Alliant Energy
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Why this discussion?
• Livestock waterers need a heat source in
northern climates
• Livestock waterers often are electrically
heated
• Livestock waterers may be a location
where stray voltage can be a concern
2
What questions do I hope to discuss?
• How does voltage get to a waterer?
• What is required or recommended for
livestock waterers (drinkers)?
• What types of waterers are available?
• What suggestions and recommendations
are there for installation?
• How and when do you test at waterers?
Assume that we are talking about waterers with
equipment grounding that are not faulting
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Three locations of a livestock
waterer
1. In a building with electrical source
2. Near a building with electrical source
3. Remote from a building with electrical
source
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Equipment Ground to a Livestock
Waterer
VC
NEV
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What questions do I hope to discuss?
• How does voltage get to a waterer?
• What is required or recommended for
livestock waterers (drinkers)?
• What types of waterers are available?
• What suggestions and recommendations
are there for installation?
• How and when do you test at waterers?
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2011 NEC 547-10
Pages 70-480,481
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NEC 547-10 FPN 1,2,3
Pages 70-480,481
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What questions do I hope to discuss?
• How does voltage get to a waterer?
• What is required or recommended for
livestock waterers (drinkers)?
• What types of waterers are available?
• What suggestions and recommendations
are there for installation?
• How and when do you test at waterers?
14
Three types of waterers
• Energy free
• Electrically heated without conductive
contacts (often plastic)
• Electrically heated (mounted or drop in
heater)
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How does
heat from
the earth
keep a
waterer
from
freezing?
Cobett
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Area of 4ft section of uninsulated pipe per diameter
Height of
uninsulated
pipe (in)
2
Pipe
diameter
(in)
Area (in ) of
bottom
3.14*r
2
2
Area (in ) of Total area
2
4ft high pipe (ft )
below
insulation
columns (3+4)/144
3.14*d*H
48
6
28
904
6.5
48
8
50
1206
8.7
48
10
79
1507
11.0
48
12
113
1809
13.3
48
14
154
2110
15.7
48
16
201
2412
18.1
48
24
452
3617
28.3
17
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Examples of overnight ice
thickness in a beef dry lot situation
• Energy free water fountains were found to function adequately
provided they are properly design , properly installed and utilized an
appropriate riser pipe. (Schott 1993 Manitoba)
• Cobett
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What questions do I hope to discuss?
• How does voltage get to a waterer?
• What is required or recommended for
livestock waterers (drinkers)?
• What types of waterers are available?
• What suggestions and recommendations
are there for installation?
• How and when do you test at waterers?
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Suggestions and
Recommendations for Installation
• For freestalls and indoor locations
– Where is electrical heat needed?
– Leave options with electrical
– Segment water lines in building, replaceable
lines, and separate lines (where possible not
under concrete), may want water line on
outside of building
– Equipotential planes
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Equipotential Planes
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Suggestions and
Recommendations for Installation
• For remote waterers consider:
– Equipotential planes
– Waterers without conductive surfaces
• Be aware of measurements due to electric fields
– Additional grounding of waterer
– Separately derived systems
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Equipotential Plane Installation
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Transition
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Equipment
Ground
EPP
V~0
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V~0
With this type of heater, there is no conductive
connection between the water and the
equipment ground
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When and How do you test at
waterers? (Case by Case)
• Address customer concerns
• Is it wired safely and correctly?
– If only two wires (no equipment ground), not safe
– No ground or plane (manufacturer’s specifications
and NEC may be time applicable)
• Need to know conditions if you are to suggest
grounding, equipotential plane, different waterer
or other options
• Best Defense is to have programs and
information available to take care of voltages of
concern
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