Datasheet
6. DEPENDENGY ON HEATER VOLTAGE
Fig. 6
Shows
the
effect
of VH
fluctuation
on
the TGS
#813's
sensitivity.
This value is based on the
R/Ro
value for methane at 1000 ppm
with an illustrated
+
4% Variation of heater voltage.
You
should
note the general principle that if the heater voltage varies
both the resistance andconsequentlythe alram
Point
for the various
gases
will
Change
accordingly.
Thus, we recommend that your heater
voltage be stabilized with a less than
+
1% Variation.
Carbon
monosade
1
OWppm/air
P
1
-7Tjlsobulane
1
OOOppmlalr
Methane
!
OOOppm
i/alr
tiiiiiitl
O.l[
I
I
I
I
I
I
1
48
5.0
52
FiG.
6.
EFFECT OF THE FLUCTUATIONS OF
KATER
VOLTAGE ON
$313
RATIO
OF
RESISTANCE
C,R/R0:.
l
Rsnurk8: Ro: Sensor
resstance
an
air
contarning
1000ppm
of
Methake
at SV
(VH).
R{
Sensor
resistance in
alr
containing
VdriouS
gases!
b
af
different
heatef
voltages.
(8)