Locating Reinforcing Bars; Practice And Training; Indications - Elcometer Protovale CoverMaster CM52 Operating Instructions Manual

3. LOCATING REINFORCING BARS

3.1 Practice and training

Because the CM52 CoverMaster is unaffected by the nature of the material covering the
reinforcing bars, the easiest way to practice location techniques is to use uncovered bars
which you can see. A block of wood or plastic of 30 to 45mm thickness can be held
between the search head and the bars to simulate the depth of concrete cover.
Starting from the simplest situation, a single straight bar, this section describes
progressively more complex situations.
uncovered bars, move on to locating covered bars in more realistic situations.
The information in this section can also be used to develop practical training courses for
site operatives.

3.2 Indications

1. Set the MODE switch to LOCate.
2. Set the DIAM switch to the estimated diameter of the bars in millimetres.
3. Switch on the instrument by turning the ZERO control clockwise. Check that the
LOW BATteries indication is not showing (a symbol of a battery in the top-left
corner of the LCD) – if it is, recharge the batteries.
4. Advance the ZERO control clockwise until you hear a 'ticking' sound or low-
pitched growl from the loudspeaker.
The CM52 CoverMaster provides three indications for metal location –
A. The analogue meter will be reading close to centre-zero. A deflection towards
the right indicates a stronger signal.
B. A faster ticking sound or a higher-pitched audible tone indicate a stronger signal.
This is generally the most convenient indication to use for normal depths
of cover.
The shallower the bar, the shriller the squeal – but conversely, deeper bars
generate a less pronounced sound. Exceptionally deep bars may not produce
enough sound – but this is solved by C below.
C. In the LOCate mode the digital display reads the strength of the eddy-current
signal from the reinforcing bar. The display indicates this by a small V symbol at
the right-hand side. Higher numbers indicate a stronger signal.
Bring a reinforcing bar close to the search head. Notice that all three indicators increase,
especially when the bar is –
1. Close to the black face of the search head
2. Parallel to the long side of the search head
3. Running along the centre-line of a flat face of the search head.
As you develop skill and confidence with
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