Start-Up Phase; Self Monitoring Transmitter; Cable Break And Short Circuit; Diagnosis And Measures - Extron electronics ExSens Instruction Manual

Instruction Manual
ExTox Transmitter ExSens(-I) and Sens(-I)

Start-up Phase

3.2.4
When over-plugging the power supply at initial operation or after a power failure
the transmitter has to stabilise itself. During this start-up phase invalid measuring
signals could trigger false alarms. To avoid this, a constant current of 0.8 mA is is-
sued during this start-up phase. The red LED on the electronic PCB inside the hous-
ing of the transmitter is blinking during this period. The duration of the start-up
phase is approx. 1 minute.
Please consider that stabilisation time of the transmitter can even be longer ( DB).

Self monitoring Transmitter

3.2.5
The transmitters dispose of large self monitoring functions. In case a fault is recog-
nized during the automatically running controls, an output current of 1.1 mA is is-
sued.

Cable Break and Short Circuit

3.2.6
Interruptions or short circuits in the lines of the transmitter cable as well as the
failure of the transmitter power supply lead to a current around 0 mA or above
22 mA. Please pay attention to the fact that also other modes can be adopted in
case the cable is not completely damaged. These would under unfavourable circum-
stances only be recognized at regularly calibration. Please also consider the specifi-
cations for maximum cable lengths and wire resistances ( DB).

Diagnosis and Measures

3.3
The 4-20 mA current output is to enable a diagnosis. To be able to observe the cur-
rent output you have to countersink a current measuring device into the 4-20 mA
line. This should preferably be done outside hazardous areas, for example at the
control unit. Alle ExTox control units provide an indication of the current on their
displays. The functions are described in the instruction manuals.
Please pay attention to the hints in Chapter 0 when working in hazardous areas.
Maybe it is necessary to uninstall the transmitter for diagnosis and removal of de-
fects and to perform the measures outside hazardous areas, for example in an elec-
tro workshop.
The table mentioned below contains all transmitter modes as well as all measures
to restore the measuring function.
Current Out-
put
(I ±0.1 mA)
out
0 mA
0.8 mA
1.1 mA
Mode
Cable Break on
(3.2.6)
Power Failure off
(3.2.6)
Start-up Phase on
(3.2.4)
Hardware on
Fault
(3.2.5)
LEDs
green red
off
off
blink- This mode is automatically
ing left after the start-up phase
(3.2.4) has been passed
on Power supply < 15 V or check
hardware and repair if neces-
sary.
Measures
Check electrical connection
Repair cable
Check power supply
Repair cable
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