Honeywell STT700 STT700, Руководство пользователя

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Page 30 STT700 Temperature Transmitter
User’s Manual
Revision 1
SYMPTOM SFC MESSAGE/
DISPLAY
POSSIBLE CAUSE CURE
Incorrect operating voltage. line resistance is not
excessive.
Unstable onscale
input "STATUS CHECK = O.K."
since any identified
problem would give upscale
or downscale fail-safe.
Bad sensor wire
connection.
Intermittent open circuit of
sensor.
Wiring disturbed by strong
electromagnetic
interference. Check connection and wiring
for intermittent connections.
Check that sensor fault
detection is "ON", this allows
detection of a bad sensor.
Protect wiring by using
appropriate grounding,
shielding etc.
Fail-safe output
signal " CRITICAL STATUS " A fail-safe output signal
(critical status) can be
caused by several reasons. The SFC will indicate the
source of the problem by
displaying the appropriate
error message.
Incorrect output
signal with
simulating device " STATUS CHECK = O.K. "
but does not correspond to
value set by simulating
device
The most common error is
changing the sensor wiring
after probe type selection or
after power-up. Check the appropriate sensor
wiring and power cycle when it
is correct.
Remember when changing
configuration to first connect
sensor wiring correctly, then
change configuration.
" INVALID
REQUEST " when
changing LRV or
URV
" INVALID REQUEST " If the LRV is changed, the
URV tries to change by the
same amount to maintain
the same SPAN. If this new
URV exceeds the URL then
this message appears. Reduce the URV or SPAN
before changing the LRV.
Non-critical status
message, without
# sign " USER CORR ACTIVE " Transmitter has been
trimmed for particular
sensor range. This can be
done by keying in
LRV/URV, CORRECT,
ENTER with exact LRV and
URV input values to enable
improved accuracy over the
specifications. When performing a Reset
Correct command or a sensor
type change, the transmitter
will lose this sensor correction
and fall back to the original
factory calibration.
Remember that successful communications with the transmitter result in many useful pieces of data. With the
initial I.D. response, the user can confirm that the:
1. Transmitter is powered
2. Line resistance is correct
Wires run to the correct unit. If not, the unit connected can be identified by the tag number.