Dräger Polytron 7000 Instructions For Use Manual page 39

Analogue signal
— A current between 4 and 20 mA flows through the transmitter during normal
operation. This current is proportional to the gas concentration.
— The Dräger Polytron 7000 transmitter uses various current values to indi-
cate the operational status of the transmitter:
Current
1)
4 mA
1)
20 mA
1)
<3.2 mA
3.8 mA ... 4 mA
20 mA ... 20.5 mA
>23 mA
static signal: 3.4 mA
dynamic AC signal: 5 mA
0.4 seconds
1)
and 3 mA for 0.7 seconds
Every 10 seconds
2)
1 second <3.2 mA
1) Output current on delivery. The values may deviate by ±0.5 mA depending on the set
offset current.
2) Factory setting. Can be configured as desired, page 71.
Exceeding or falling below the transmitter supply voltage specified in the
technical data can lead to an incorrect display of the analogue signal!
Display
— In measuring mode, the display shows the actual gas concentration, e.g.:
An alarm is triggered:
— when rising above - for O
concentration alarm,
— When the full scale deflection is exceeded:
The special symbol »
value.
— The measured value drops below the measuring range:
The special symbol »
value.
Meaning
Zero point
Full-scale value
Transmitter fault
1)
Sensor drift below zero point
1)
Full-scale value exceeded
Fault in analogue output
1)
Maintenance signal and signal during
1)
for the warm-up period
(configured on delivery: static)
2)
for Warning signal
1)2)
(factory setting: off)
CAUTION
also when falling below - the alarm levels for the
2
« is displayed instead of the measurement
« is displayed instead of the measurement
20.9
O Vol.%
2
19.0
O A1
2
Y Y Y Y
O Vol.%
2
X X X X
O Vol.%
2
Start-up
39