Ion Science TVOC - Manual (Page 9)

TVOC MANUAL Ion Science Ltd
Page 9 of 32
Unrivalled Detection. www.ionscience.com
Diagram 3
TVOC setup
Selector Pins
TVOC has a number of settings that can be selected by the
user via a row of four selector pins mounted on the reverse side
of the main PCB. Diagram 2 shows the location of the functional
selector pins labelled - A, B, C & D.
The selector pins absence or presence determines the chosen
setting.
TVOC is shipped with all four selector pins fitted as shown in
diagram 3.
Diagram 4 shows the removal of 1 selector pin.
The following table shows the selector pin combinations and the corresponding function.
= Selector pin fitted  = Selector pin removed
Selector pin
A B C D Range Displayed units
    1000 ppm (Default)
  x  100 ppm
 x   10 ppm
   x 2280 mg/m
3
  x x 228 mg/m
3
 x  x 22.8 mg/m
3
Selector pin ‘B’ and ‘C’ selects the ranges - 10 ppm, 100 ppm or 1000 ppm
Selector pin ‘D’ selects the units - ppm’ or ‘mg/m 3
Selector pin ‘A’ - Fault output range
NOTE: During an Alarm condition (F1 or F2) the output will drop to either 3.5 mA or 2.0 mA.
Jumper ‘A’ fitted: 3.5 mA during an alarm condition
Jumper ‘A’ removed: 2.0 mA during an alarm condition.
As default, the TVOC has a 100 ppm factory calibration
Diagram 2
Diagram 4