Electrical Conductors and Connectors

DOE-HDBK-1092-2004

1. Provide sensing devices (temperature, coolant-flow) that are interlocked with the power

source.

2. Fabricate protective enclosures from materials not adversely affected by external

electromagnetic fields. Researchers should consider building a nonferrous barrier designed

to prevent accidental attraction of iron objects and prevent damage to the cryostat. This is

especially important for superconducting magnet systems.

3. Provide equipment supports and bracing adequate to withstand the forces generated during

fault conditions.

4. Appropriately ground electrical supply circuits and magnetic cores and provide adequate

fault protection.

5. Provide means for safely dissipating stored energy when excitation is interrupted or a fault

occurs.

6. Provide appropriate warning signs to prevent persons with pacemakers or similar devices

from entering areas with fields of greater than 0.001 Tesla.

7. Personnel exposure to magnetic fields of greater than 0.1 Tesla should be restricted.

8. When a magnet circuit includes switching devices that may not be able to interrupt the

magnet current and safely dissipate the stored energy, provide a dump resistor connected

directly across the magnet terminals that is sized to limit the voltage to a safe level during

the discharge and safely dissipate the stored energy.

10.10.2.3

OPERATION AND MAINTENANCE

Verify that any inductor is de-energized before disconnecting the leads or checking continuity or

10.10.3 ELECTRICAL CONDUCTORS AND CONNECTORS

The conductors and connectors covered here are only those used in unconventional

applications.

10.10.3.1

HAZARDS

Examples of hazards are as follows:

1. Metallic cooling-water pipes that are also used as electrical conductors present shock

hazards (i.e., they may not be readily recognizable as electrical conductors).

2. Improper application or installation of connectors can result in overheating, arcing, and

shock hazards.

3. Hazardous induced voltages and arcing can result from inadequate separation between

high- and low-voltage cables.

4. Use of an improper cable for a given type of installation (routing) can result in a fire hazard.

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