Cambridge Sensotec Rapidox 1100E Oxygen Analyser Instruction Manual
Version 3.8
11
Last printed 29/08/2012 16:01:00
cleared. Additional current and voltage signals are provided by the analyser to
give an indication of various conditions and these are described in Table 3 below,
together with the status of the alarms during the condition:
O
2
Analogue Outputs
Description
Explanation
Alarms
(3)
Current
(1)
(4-20mA)
Voltage
(2)
(0-10V)
1mA
0.5V
Fault
There is a sensor fault on the oxygen
sensor, and/or the pressure mode is
set to automatic (pressure
compensation active) and the pressure
sensor has a fault condition.
De-activated
2mA
1V
Start up
The analyser is still initialising.
De-activated
2.5mA
1.25V
Sensor under range
The sensor reading is under range.
Active
3mA
1.5V
Sensor over range
The sensor reading is over range.
Active
3.5mA
1.75V
Sensor operating out of
specification
The sensor reading is in range but the
pressure mode is set to automatic
(pressure compensation active) and
the pressure sensor is out of range.
Active
4 to 20mA
0 to 10V
Normal operating output
The O
2
sensor and pressure sensor
are operating normally and readings
are in range.
Active
Pressure Analogue
Outputs
Description
Explanation
Alarms
(3)
Current
(1)
(4-20mA)
Voltage
(2)
(0-10V)
1mA
0.5V
Fault
The pressure sensor has a fault.
De-activated
2mA
1V
Start up
The analyser is still initialising.
De-activated
2.5mA
1.25V
Sensor under range
The pressure sensor reading is under
range.
Active
3mA
1.5V
Sensor over range
The pressure sensor reading is over
range.
Active
4 to 20mA
0 to 10V
Normal operating output
The pressure sensor is operating
normally and readings are in range.
Active
Table 3: Analogue output settings and alarm status for certain conditions
Notes:
1
The current outputs are active self-powered outputs - they are not loop powered.
2
The voltage (0 to10V) outputs produce non-zero voltages during start-up, fault and over/under range conditions - if
1V to 5V outputs are required, with these conditions indicated by corresponding voltages between 0V and 1V, the
current outputs can be used, with a 250 Ohm load resistor.
3
Alarms are de-activated during start up initialisation, and when a fault condition occurs on the assigned sensor.
6.9
Setting the Display Units
The notation used by the display is fully programmable to suit your needs using
the keypad (2) or the software provided. The following options are available to
you:
1.
Oxygen: The oxygen reading can be displayed in percent (e.g. 20.95%),
ppm (e.g. 209500ppm) or in terms of pressure (using the pressure units set
as below). There is also an option to display the oxygen reading in terms of
a nitrogen balance (%N
2
) reading. In this case the reading displayed is 100-
O
2
% =N
2
so for example in air 21% the nitrogen balance reading will
display 79% N
2
. Note that this is NOT an actual nitrogen analysis.
2.
Pressure: The reading can be displayed in mbar, bar, psi, torr or kPa.
To program these options scroll down to menu no. 4 “Set Units” and press ENT.
Use the ENT key to progress through the list and the UP & DOWN keys to select
Summary of Contents for SENSOTEC Rapidox 1100E
Page 46: ......
