
DSP-100 User Manual
Page 18 of 25
DSP100_MAN_A
6.
Configuration
Basic DIP Switches
The front panel DIP switches facilitate easily
changing most of the operating parameters of the
DSP-100 detector.
When a DIP switch is moved toward the numbers
printed on the DIP switch, the switch is in the OFF
position. When mov
ed toward the “ON” printed on
the DIP switch, the switch is in the ON position.
The basic detector has the DIP switch on the right
and does not have the Delay and Extension DIP
switches on the left side. The detector front panel
pictured to the left is a DSP-100T detector with
timing features.
Frequency (Switches 5 & 6)
–
These two switches select the amount of capacitance added to the loop circuit.
The more capacitance the lower the operating frequency. To aid in avoiding inductive coupling (cross-talk) of
loops, each DSP-100 unit comes with two frequency switches. They are binary coded allowing up to four different
frequencies to operate at. If there are suspicions that loops are interacting, change one of the detector’s
frequency settings.
DIP Switch
Frequency
5
6
OFF
OFF
High
OFF
ON
Medium High
ON
OFF
Medium Low
ON
ON
Low
Presence / Pulse (Switch 4)
–
This switch selects what output mode the detector operates in. When the switch
is off, the detector will operate in the presence mode. The output will be activated while a vehicle is detected
over the loop. When the switch is on, the detector will operate in the pulse mode. The output will activate for
125 milliseconds when a vehicle is detected. Delay and Extension features will modify how the output responds
in either mode.
Sensitivity (Switches 1, 2, & 3)
–
These switches select one of eight possible sensitivities of the detector. Like
most inductive loop vehicle detectors, the DSP-100 directly measures the change in frequency of the loop and
from there, calculates the change in inductance when a vehicle interacts with it. The change in inductance is
measured as -
ΔL/L
(reads as “minus delta L over L”) and is usually expressed as a percentage.
Figure 11: Front Panel DIP Switches