Lead Bushings at the ATEX Enclosure

 

Operational safety!

  • All lead bushings have to be installed with a metallic counter nut.
  • When using lead bushings with strain relief and bending protection, the number of possible standard screw joints is reduced.
  • A mixed assembly of lead bushings can be used. Areas for intrinsically safe circuits have to be marked separately.
  • Unused openings for lead bushings have to be closed with ATEX-certified closing plugs made of cold impact resistant plastic or metal.
  • The lead bushings have to be mounted in such a way that they do not loosen automatically and a permanent sealing of the cable and lead entry points can be guaranteed. Cable ties are used to fix the cables.
  • The distances between the lead bushings have to be selected so that a torque wrench can be used to tighten the lead bushings and the cap nuts.

 

In order to connect the DetCon detonation controller to other devices, you have to make suitable lead bushings. Observe the maximum number of cable and lead bushings for each side of the enclosure in order not to impair stability. Afterwards put the leads through the bushings in the enclosure wall and fasten them. Observe the tightening torques specified by the manufacturer.

DetCon_ATEX_Leitungsdurchführungen

Maximum Number of Lead Bushings

The maximum number of lead bushings depends on their size.

The maximum number for each side of the enclosure is selected according to the following table so that the side walls are not weakened and the stability of the enclosure is not impaired.

Screw size

Side A

Side B

Side C

Side D

M12

33

31

33

33

M16

19

17

29

29

M20

16

14

16

16

M25

13

11

13

13

M32

4

2

9

9

M40

3

1

3

3

M50

2

1

2

2

54_DetCon_Gehäuse_Seiten

Type examination certificate

All cable and lead bushings have to own a separate EC-type examination certificate.

The closing plugs used require a separate EC-type examination certificate.

Tightening Torques

When installing the lead bushings, the tightening torques have to be observed. If no specifications are available, the following values should be used.

Size

Tightening torque

Bore hole diameter

Socket

Cap nut

Counter nut

Brass/
Polyamide

Brass

Polyamide

Brass/Polyamide

M12x1.5

2.5 Nm
(1.8 lb-ft)

2.0 Nm
(1.48 lb-ft)

2.5 Nm
(1.8 lb-ft)

12.5 mm
(0.49")

M16x1.5

4.0 Nm
(2.95 lb-ft)

2.5 Nm
(1.8 lb-ft)

4.0 Nm
(2.95 lb-ft)

16.5 mm
(0.65")

M20x1.5

4.0 Nm
(2.95 lb-ft)

2.5 Nm
(1.8 lb-ft)

3.5 Nm
(2.58 lb-ft)

4.0 Nm
(2.95 lb-ft)

20.5 mm
(0.81")

M25x1.5

7.5 Nm
(5.53 lb-ft)

12.0 Nm
(8.85 lb-ft)

5.0 Nm
(3.69 lb-ft)

7.5 Nm
(5.53 lb-ft)

25.5 mm
(1.00")

M32x1.5

7.5 Nm
(5.53 lb-ft)

12.0 Nm
(8.85 lb-ft)

7.5 Nm
(5.53 lb-ft)

32.5 mm
(1.28")

M40x1.5

7.5 Nm
(5.53 lb-ft)

12.0 Nm
(8.85 lb-ft)

7.5 Nm
(5.53 lb-ft)

40.5 mm
(1.59")

M50x1.5

7.5 Nm
(5.53 lb-ft)

12.0 Nm
(8.85 lb-ft)

7.5 Nm
(5.53 lb-ft)

50.5 mm
(1.99")