Scanning for Live Wires, Lath and Plaster

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Detection Through Special Surface Materials

Lath and Plaster

Because of the uneven thickness of the plaster, it is difficult to detect wood studs using the wood detection mode. It will probably be easier to locate the studs by changing to the metal-detection mode to locate the nails that hold the lath to the studs.

Lath and Plaster with Metal Mesh

Reinforcement

(See SCANNING IN METAL–DETECTION MODE).

Textured or Acoustic Walls and Ceilings When scanning a wall or ceiling with an uneven surface, place thin cardboard on the surface to be scanned and scan over the cardboard. In wood-detection mode, calibrate with cardboard in place.

Wallpaper

If paper contains metallic foil, metallic fibers, see SCANNING IN METAL-DETECTION MODE. If paper is wet, it must be allowed to dry before scanning.

Wood Flooring, Wood Subflooring and

Drywall Over Plywood Sheathing

Because of the thickness of these materials, it is difficult to detect wood joists or studs using the wood-detection mode. It will probably be easier to locate these items by changing to the metal-detection mode to locate the nails that hold the materials to the joists or studs.

Carpeting

The DMD4 cannot detect wood studs and joists through carpeting. It might be possible to use the metal-detection mode to locate nails or screws that were used to attach the wood floor to the joist.

Scanning for “Live” Wires

The multi-detector can indicate “live” wires/conductors with 50 or 60 Hz of 120V AC or at higher voltages. If other wires/conductors are detected, they are indicated only as metal objects. “The multi-detector automatically scans for “live” wires/conductors in both the metal mode and wood mode.

When a “live” wire/conductor is detected, the indicator a appears in the display. Move the multi-detector over the surface repeatedly in order to locate the “live” wire/conductor more precisely. After moving the multi-detector over the surface several times, the “live” wire/conductor can be located quite precisely. If the multi-detector is very close to the wire/conductor (four or five bars in indicator a), the illuminated ring 1 flashes red and the signal tone sounds with a rapid tone sequence.

•“Live” wires/conductors can be detected more-easily when power consumers (e.g., lamps, appliances) are connected to the wire/conductor being sought and switched on.

•Wires/conductors with 110 V, 240 V and 380 V (three-phase current) are detected with about the same scan capacity.

•Under certain conditions (such as when behind metal surfaces, shielded in conduit or behind surfaces with high water content), “live” wires/conductors cannot be detected with certainty. These ranges may be recognized in the metal detection mode as metal objects.

•Wires that are not “live” might be detected as metal objects with the metal-detection mode. However, unlike solid copper cables, stranded copper cables are not detectable.

•When “live” wiring is detected over a wide area, the scan for “live” wiring is not reliable because something in the surface material is shielding or distorting the electrical field.

	! WARNING	Before penetrating a
	! WARNING	surface (such as with a
		surface (such as with a

drill, router, saw or nail), always shut off the electrical power, gas and water supplies. Cutting, drilling, etc… into these items when operational can result in personal injury.

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