Brochure/Catalogue

Installation instructions for data interfaces

The supply and earth lines of the protective modules should

be kept short in order to achieve optimum protection for the

data terminals.

Likewise, the transmission paths should also be kept as short

as possible because the longer the line, the greater is the

chance of interference having an effect.

Inserting surge protection increases the attenuation of the

line and so changes the signal-to-noise ratio.

Installation position

Protective modules are frequently installed at both ends of

the line.

It is important to ensure that protected and unprotected

lines are routed separately. Further, there should be some

clearance between power lines and data lines. A common

cable duct must be subdivided with metal partitions.

Shielded lines for data interfaces

Systems involving several buildings should be designed with

cable shielding capable of carrying current. These data lines

often have two shields: one for carrying transient currents,

the other as protection against coupled interference.

Circuit concepts

High transmission frequencies place greater demands on

surge protection in protective circuits for data interfaces. Gas

discharge tubes are frequently the sole means of protection

in these cases. However, the disadvantage of this is that the

protection level is very high. Lower protection levels can be

attained at high transmission frequencies by using special

low-capacity suppressor diodes.

D.212028840000

Lightning and surge protection

for data interfaces