ULT-
PLG™ Operating Instructions
8
Document no.
10180904
Troubleshooting
Symptom
Possible cause
Solution
Green LED flashes
Loop wire shorted or open
Check loop resistance on the
appropriate loop pins on the
control board connector,
between .5 ohms and 5 ohms.
Green LED flashes, 2 fast Loop was previously
shorted or open
Check loop resistance on the
appropriate loop pins on the
control board connector.
Detector remains in
detect after vehicle has
left loop
1.
Faulty loop
2.
Poorly crimped
terminals
3.
Loose connections
1.
Perform megger test from
loop lead to ground, should
be >100 megaohms
2.
Check loop connections to
terminals
3.
Check splices are properly
soldered and sealed against
moisture
4.
Observe ULTRAMETER
display, level indicated on
display indicates residual
frequency shift from vacant
loop to vehicle presence,
press Frequency Count switch
to re-initialize the detector
Intermittent detection
1.
Faulty loop
2.
Poorly crimped
terminals
3.
Loose connections
4.
Cross-talk between
adjacent loops
1.
Perform megger test from
loop lead to ground, should
be >100 mega ohms
2.
Check loop connections to
terminals
3.
Check splices are properly
soldered and sealed against
moisture
4.
Set adjacent loops to
different frequencies (see
Frequency Setting)
No detection
1.
Loop wire shorted or
open
2.
Loop sensitivity set too
low
1.
Check loop resistance on the
appropriate loop pins on the
control board connector,
between .5 ohms and 5
ohms.
2.
With vehicle on loop, observe
ULTRAMETER display, set
sensitivity to the level
indicated on the display
