Sld4 Sensitivity; Table 3 : Link And Switch Function; Table 4 : Inductance Jumper Settings For Detection - Siemens SLD4 Application Notes

General Setup
Link Function
Function
Link
PL3 Loop 1 inductance setup links
PL4 Loop 2 inductance setup links
PL5 Loop 3 inductance setup links
PL6 Loop 4 inductance setup links

Table 3 : Link and Switch Function

Sensitivity Settings
Jumper Setting
Range
1 1-2, 3-4
2 2-3, 4-5
3 1-2 ,4-5

Table 4 : Inductance Jumper Settings for Detection

Note
In practice inductance ranges overlap so it is possible to use a lower range in some circum-
stances. This may give better performance, particularly for bicycle detection.
2.2.

SLD4 Sensitivity

The detector threshold may either be set in "Hz" or as a percentage of loop inductance
change ( . Which you use only depends upon which is most convenient for the applica-
%ΔL/L )
tion. In general, it is recommended that "Hz" mode is used for large vehicles (tram, bus), as
this provides easier value adjustment for large vehicles. The value is a whole number in the
thousands range, for an inductance change it would be a two decimal place number.
The "Hz" setting is slightly dependent upon frequency, so if you change the loop frequency
then the sensitivity in "Hz" may need to be changed higher or lower in proportion to the loop
frequency change. This is the disadvantage of using the "Hz" setting mode.
Detector Variant Differences
The standard SLD4 detector supports only "Bicycle" mode whereas the remaining modes re-
quires an enhanced SLD4 detector.
Loop Detector Application Notes SLD4
667/HQ/45200/101
Inductance Range
20-150uH
150uH-300uH
260uH-2000uH
10