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The LT-1000M in-pavement loop tester
Enhanced features from the LTM100
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Loop Location – moving vehicle, audible ‘ping’ when loop detected
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Loop ‘winding’ location – hand held operation walking on road surface
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Loop wire Insulation Integrity
This is a field service device suitable for in-pavement loop analysis. The device has an LCD display
which displays all relevant in-pavement loop parameters including; DC Resistance, Inductance, Loop
‘Q’, Loop tuned frequency, insulation integrity and Loop location. Additionally an analogue bargraph
display indicates a vehicle actuation and relevant energy change associated with the actual vehicle
detection.
This purpose designed, rugged, portable hand held device connects to loop feeder cables via flexible
leads with ‘alligator’ style clips. The loop location function requires an external ‘ tuned’ probe. The
device has an LCD panel for displaying relevant loop parameters. The device has a single power-ON /
OFF momentary switch and for night-time use the touch sensitive keypad for backlight operation will
activate the back light when selected to save energy. The analyser is powered by a single 9V D cell.
The device will automatically switch OFF after a preset period to enable longer battery life – WHEN
disconnected from a loop. Activating the ON button ‘wakes up’ the internal microprocessor which
then controls battery power for a preset period. Inactivity will cause the microprocessor to return to
‘sleep’ mode. The OFF function is selected via the ON /OFF switch which is a momentary operation
in both directions
There are no external adjustments. The device will automatically detect the loop parameters and report
the parameters on the LCD screen. The device indicates battery voltage and when the battery becomes
low should be replaced in order for the internal measurement circuit to produce an error free analysis of
the loop parameters.
The field technician can identify the following in-pavement loop verification
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The DC Resistance of the loop and feeder
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The Inductance of the combined loop and feeder
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The Tuned frequency of the loop and feeder
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The ‘Q’ of the combined loop and feeder
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Quickly identify ‘short-circuits’
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Quickly identify ‘open-circuits’
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Loop position within the pavement identified from a moving vehicle (max speed 110khr)
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Loop wire (winding) lo\- 1 cm (hand-held operation)
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Loop wire insulation integrity >100Megohms
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Loop operation incorporating an analogue bargraph display of the actuation
