Intermittent faults?
T
he bane of the service engineer’s
life.
A problem is reported… you
arrive on site… and the system behaves
perfectly….
Similar fault reported a week later, and
history repeats itself.
Maybe you replace a sub-system and
cross your fingers hope that cures it…
but a week later….. guess what!
The FTR Faultracker is a compact
recording device which can be connected
to up to 16 points in any electrical
control system.
Any voltage from 12v dc to 240v ac can
be connected. The FTR monitors the on/
off status of each input. Any voltage
above 6v is considered to be ON. An LED
indicator on the front panel shows the
status of each input. When set to logging,
the FTR will log any and all 'events'.
An event being the change of status of
any input. Each event is logged strictly
in the order it occurred with a date/time
stamp. When logging is completed, the
events can be stepped through one at a
time so that cause/effect sequences can
be analysed.
This means that faults which cause
significant disruption and are very
difficult to track can be stepped through
in great detail, even if the sequence
involved events that are separated by
only milliseconds.
Also, many problem situations are
intermittent. The FTR can be left logging
for hours or days or weeks until the fault
occurs.
The memory is capable of storing many
thousands of ‘events’. When the ‘problem’
occurs again, the recording can be
analysed on your PC using the software
included with the FTR and the fault
sequence tracked in detail, complete
with date and time stamps. That mystery
‘event’ that caused the problem can now
be revealed.
Once this is identified, the solution
becomes obvious.
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Key Points Typical application
• Monitors up to 16 locations
simultaneously • Records exactly what happens
within millisecond accuracy • Enables fault origin to be located
easily and quickly • Ideal for those intermittent faults • Can be set to monitor for extended
periods, and to trigger logging for
specific input conditions • Logging up to 32,000 events. • RS232 interface for download to PC • Extensive view and analysis modes
on the PC. • Step though complex sequences on
step at a time. • Any input from 12v to 240v can be
connected. Lift installation at xxx department store,
Manchester. Occasionally, typically twice
a month, the system locks out. The many
control and sensor signals presented to
the plc appear to be working correctly.
Stepping the system in slow sequence
did not show any problem. Using a
conventional data logger was not an
option because the signals varied from
12v dc to 240v ac and included 24v
ac and dc, plus 110v ac. One of the
advantages of the FTR is that it will
accept this full range of voltages on any
input, without any configuration hassles.
Connecting the FTR and allowing the
system to run until the fault occurred
enabled the exact sequence of events
that led up to the problem to be studied
in detail. In particular, the order in which
signals changed could be analysed,
one step at a time. This showed that
a momentary pulse from a proximity
sensor was initiating an operation
before its proper time. This occurred only
when the lift was running non-stop and
empty past the 3rd floor. Checking the
operation of the sensor showed that its
threshold adjustment had slipped. This
gave an occasional false output only
when the lift was travelling past it at
high speed. Five minutes work with a
spanner and all was well. This one such
instance paid for the FTR several times
over!
The standard FTR-C version includes
Windows software which will download
the data from the FTR, record it to your
chosen drive and display the results on
screen.
These results can be presented in
a variety of formats which can be
organised either by date/time or event
number.
Search tools are included so that
particular combinations of input status's
can be instantly located.
www.faultracker.com