WEBVTT

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A hole through a core limb

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removes steel from
the magnetic section.

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Magnetic flux must
bend around it,

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and punching can
leave a stressed,

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burred edge.

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A through-bolt also
needs correctly

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designed insulating
sleeves and washers.

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If that insulation
fails and a

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conductive loop
links changing flux,

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circulating current
can cause local

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heating.

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Glass-fibre limb bands
offer a different

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design route, without
a through-hole in

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the limb.

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Their material, tension
and spacing still

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need engineering control.

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Bolts can remain
appropriate in other

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parts of a core when the

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design provides for them.

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Compare the complete
clamping design,

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not the label alone.