Magnetic Autocontrol MHTM, Руководство по эксплуатации

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Barrier MHTM
TM
MicroDrive Access and Parking
Assembly and installation
58 5815,5001EN / Version 05
8.4.2 Induction loops
The induction loops are available as ready assembled cables in
various lengths from MAGNETIC.
Alternatively a loop can be manufactured from single wire. The
following requirements must be fulfilled:
 Wire cross section: 0.75 to 1.5 mm
2
 Inductance of the loop: 70 to 500
μ
H. This is equivalent to a
loop with 3 to 6 windings.
 When using hot pouring compounds, such as bitumen
temperature resistant loop cables/strands must be used.
8.4.3 Testing induction loops
To verify the contact resistance, insulation resistance, and
inductance of the loop these properties must be measured after
installation:
 Contact resistance: 0.8 to 2.0 ohms
 Insulation resistance to earth: > 1 Mohm.
 Inductance of the loop: 70 to 500 μ H
If the values are not within the specified ranges, the loop is
defective.
8.4.4 Installing induction loops in bitumen, asphalt, or concrete
1. Cut a 50 mm deep groove into the surface or asphalt using a
cutting disc. The groove must be equally deep at every point.
According to Fig. 14 the corners of the groove must be cut in a
45° angle.
Mag00085
3
1
4
2
Fig. 19: Installing induction loop in bitumen, asphalt, or concrete
1 Groove for induction loop feed line
2 Corners cut diagonally
3 Groove for induction loop
4 Induction loop