RIKEN FI-21 User manual

OPERATING
INSTRUCTIONS
RIKEN PORTABLE ANESTHETIC GAS INDICATOR
| MODEL FI-21
Manufactured by:
Riken
Keiki
Fine
Instrument
Co.,
Ltd.
2-7-6,
Azusawa,
Itabashi-ku,
Tokyo,
JAPAN
Distributed by:
A.M. Bickford, Inc.
12318 Big Tree Road
Wales
Center,
N.Y.
14169
Tel: [phone]
Fax: [phone]

NN
Index
A
NNNN
λα
9.
PART
AND
THE
FUNCTION..............:.::::cecscsessssessesseesessnenensenenenssesesasecseseenseseeasssesttesecasensnsnenssensenenensee!
MEASURING MODE (POWER KEY)
2-2. PROCEDURES FROM POWER ON TO MEASUREMENT.
2-3.
:
SAVING
DATA
menti
RSS
LENE
ned]
2-4,
INITIAL
DISPLAY
(SELF-DIAGNOSTIC
DISPLAY)
2-5
—
¡ERROR
MESSAGE
DISPUAV
reles esser
essens
dl onontossontesssonenenvetorommeretesema
2-6.
AIR
CAL.
CAUTION................
тие
О
ева
ранив
2-7.
AFFECTION
ON
MEASUREMENT
FROM
PRESSURE..................
SETTING
MODE
(ENTER
+
POWER)...
inner
nene
3-1. CHANGING THE MEASURING GAS (SELECT GAS)
3-2. ADJUSTING THE TIME (SET DATE / TIME)....................
3-3. CONFIRMING THE SAVED DATA (VIEW SAVED DATA)
3-4. CLEARING THE SAVED DATA (CLEAR SAVED DATA).....
3-5. START THE MEASUREMENT ( START MEAS.
4-2.
4-3.
TROUBLE SHOOTING.
CAUTION ON USAGE ......
DEFENITION OF TERMS..
te
8-1. SPECIFICATIONS......................
8-2. STANDARD ACCESS! ORIES
ra WARRANTY scalini ade aşağ
MEASURING PRINCIPLE.

1.
Part and the Function
TOP ©
FAN SAVE EC
| SAMPLIN
POWER
CANCEL
4
n
ENTER
©
N 2:00
1.57 vol%
HALOTHANE
In 02
Fl-21
GAS
INDICATOR
RIKEN
KEIKI
(D | POWER key:
Press
this
key
one
time
to
tum
the
power
on.
Keep
pressing
the
key
approx.
3
seconds
to
tum
the
power
off.
When
pressing
the
POWER
key
and
(D
ENTER
key,
you
can
enter
the
“SETTING MODE”.
(2 | LCD Display:
Concentration is displayed. And also, time, battery remainder, measuring gas and base gas
are displayed.
© | LED for “SAMPLING” :
While the internal pump is working, this LED is on.
PUMP key (CANCEL):
When this key is pressed once, the internal pump starts to work. When the key is pressed
again, the pump stops.
(Contents selected by İV, A keys] are cancelled by this key.)
SAVE key ( W key ):
Information about Time/ Date, Measuring Gas, Base Gas, Displayed Concentration is saved
by this key. The maximum number of data points is 100.
(This key is used to enter numbers or to move the cursor.)
RANGE key ( A key ):
Position of the decimal point on the concentration display can be moved by this key.
(This key is used to enter numbers or to move the cursor.)
AIR CAL. key ( ENTER key )
When calibration is performed with standard gas, this key is used.
(Contents selected by | VW, A keys | are fixed by this key.)
Buzzer
It beeps when the power turns on/off, or when special control or wrong operation is
performed.
@) | There is a data logger interface under the cover.
* Explanations in the ( ) are for use during SETTING MODE.

Right Side
Bottom
0 GAS IN Inlet for measuring gas. A specific absorption tube must be connected to the inlet.
Otherwise, the reading might go wrong.
(D REF. OUT Outlet connected to the reference gas chamber. The exhaust from the outlet has
to be emitted into the fresh air at atmospheric pressure.
@ GAS OUT Outlet for measuring gas sucked from the GAS IN.
(3 осву 6VDC Interface for the specific AC adaptor.
@ REC. A jack for 0—1VDC output.
(Battery Cover | Cover for the battery box.
(9 Screw Fixing screw for the battery cover, It can be open/ close by a screwdriver or coin.
Tubing Structure
FI-21
m
Absorption
Tube
Re
bm
|
|
Ref.
Gas
||
REF.
OUT
Gas
IN
|
Chamber
|
| Meas. Gas ||
T
Chamber
:
а
I
GAS
OUT
Optic Pump
Interferometer
Sensor

2.
MEASURING
MODE
(POWER
key)
2-1.
Basic
Display
for
Measuring
Mode
and
Explanation
When data is saved, this
symbol appears.
Battery remainder
24 Hour Clock
ας
já
© ma 24:00?
1. 57 volk—
Concentration and units are
displayed. When the SAVE
key is pressed, the data No.
CHECK AIR CAL.
HALOTHANE ET
Display Contents Status
κα. Usual measuring mod
And Base Gas Е É
CAUTION Zero drifting might be occurring. Let the monitor sample the fresh
air and perform AIR CAL.
CAUTION
ABNORMAL TEMP.
Internal thermistor detects an abnormal temperature.
LOW BRIGHTNESS
CAUTION 。
LOW BATT Battery voltage is low. Replace the batteries.
CAUTION Interferometer sensor is getting contaminated. Before the
LOW ‘CONTRAST measurement is performed, the sensor should be replaced or
repaired,
CAUTION Brightness is getting low. Before. the measurement is performed,
the sensor should be replaced or repaired.
A Caution
When a message
soon as possible.
"CAUTION ~ ”
appears on the LCD, make an appropriate treatment as

2-2.
Procedures
from
Power
ON
to
Measurement
1)
Power
turns
on by
pressing
the
POWER
key
until
buzzer
beeps.
And,
the
initial
display
(self-diagnostic
display)
shows
up.
It
then
turns
to
a
display
to
confirm
the
setting.
After
showing
the
confirmation
display
for
2
seconds,
it
goes
to
the
basic
display
of
measuring
mode.
ga
12:00
qa
12:00
BATTERY
・・・
OK
SETTING
NO.
5
CONTRAST・・・
OK
HALOTHANE
BRIGHTNESS:
OK
in
02
JAN.
30
2001
0.
0-10.
Ovo
l%
Self-diagnostic
Display
Confirmation
Display
A Caution
This instrument does not indicate a correct reading if the measuring gas and base gas are not
selected properly. Confirm if [Measuring Gas] and [Base Gas] are the ones intentionally selected.
2) After that, two of the messages, [Meas Gas/ Base Gas] and [Air CAL], are displayed by turn as
below. (Refer to WARNING AIR CAL.)
12:00 12:00
volé | —> | ーーー-wol
CAUTION > Recente HALOTHANE
CHECK AIRCAL. by turn in O2
3) Press the PUMP Key and let it sample enough κο
reference gas (fresh air). (The color of the display — O 1 5 VO | Of
reverses
while
the
pump
is
operating.)
CAUTION
CHECK
AIRCAL.
4) After the indication becomes stable, stop the pump za 12:00
1. 57 vol“
HALOTHANE
in O2
and keep pressing the AIR CAL key until buzzer
beeps.

A Caution
Press AIR CAL key after confirming there is engh fresh air in the chamber. Otherwise, correct
measurement cannot be performed.
* Note
If the [AIR] is selected as the base gas, the indication shows [0.00vol%] when the AIR CAL
key is pressed. However, If the [02] is selected as the base gas, the indication does not show
Ovol*, but other vaulues determined based on the conbination of the measuring gas and
De gas. This is caused by sampling the gas which is not on target. (In this case, it is air.)
Do
not
think
it
broken.
Once
the
instrument
samples
the
target
gas,
it
shows
a
correct
reading. For further information, refer to the spec pages.
A Caution
FI-21
performs
best
when
both
Gas
Chamber
and
Reference
Chamber
are
at
the
atmospheric
pressure
(101.3kPa).
While
the
measuring
gas
is
being
sampled,
the
pressure
in
the
Gas
Chamber
becomes
slightly
different
from
the
atmospheric
pressure,
and
the
analyzer
does
not
show
the
correct
reading.
Read
the
indication
after
the
gas
flow
stops.
* Note
FI-21
measures
the
gas
best
when
both
Gas
Chamber
and
Reference
Chamber
are
at
101.3kPa.
If
precise
measurement
is
required,
perform
the
pressure
correction
by
the
following
method.
101.3 [kPa]
Pressure
Correction
=
x
(Reading
—
Air
Cal.
Value)
+
Air
Cal
Value
Pressure at measurement [kPa]

2-3. Saving Data
Once
the
SAVE
key
is
pressed,
the
buzzer
beeps
and
the
display
shown
on
the
right
comes
up.
The
time/
data
and
the
measurement
result
are
saved
chronologically
from
No.001
to
No.
100.
The
saved
data
can
be
seen
at
“VIEW
SAVED
DATA”
in
the
SETTING
MODE.
Also, the
saved
data
is
deleted
at
“CLEAR
SAVED
DATA”
in
the
SETTING
MODE.
2-4. Initial Display (Self-diagnostic Display)
At starting with the MEASURING MODE by pressing POWER
Key the self-diagnostic function automatically startsto work If
the result is normal, display shown on the right side is displayed.
If any problem was found on any of the items, it is indicated like
the display on the right. The display is an example for
contamination of the interferometer. If the problem becomes
serious, the display does not go to the Basic Display of the
Measuring Modebut goes toERROR message display.
M e 12:00
SAVE DAT
HALOTHANE
in O2
ma 12:00
BATTERY +++ OK
CONTRAST: : = OK
BRIGHTNESS: OK
JAN. 30 2001
aj 12:00
BATTERY ・・・ OK
CONTRAST... LOW
BRIGHTNESS・ OK
JAN. 30 2001

2-5. ERROR Message Display
If
the
problem
affects
the
measurment,
ERROR
message
like
the
display shown on the right appears.
ga 12:00
ERROR: SYSTEM
ERROR message and the meanings are as follows:
Contents of Display
The Meanings and the Required Treatments
ERROR:LOW BATT.
Battery voltage is too low to perform the measurement. Replace the
batteries.
ERROR: CONTRAST
Contamination of the optic interferometer sensor is too serious to
perform the measurement. Replace the sensor or have it repaired.
ERROR: BRIGHTNESS
The brightness is too low to perform the measurement. Replace the
sensor or have it repaired.
ERROR: SETTING
The setup data saved in the setting mode has an error. Confirm the
setup data in the setting mode, and set the data again.
ERROR:SYSTEM
A system error has occurred. Repair work is required.
ERROR:PUMP
There is a possibility that the pump is not working. Pump replacement is
required.

2-6. AIR CAL. CAUTION
If
the
temperature
inside
of
the
sensor
has
changed
over
+
10°C
from
the
last
time
the
AIR
CAL
was
performed,
[CAUTION/
CHECK
AIR
CAL]
is
displayed
in
order
to
protect
fromzero
drifting.
([Measuring
Gas/
Base
Gas]
and
[AIR
CAL]
are
displayed
consecutively.
#4
12:00
za
12:00
-
0.1
vol%
|
<->
—
0.1
vol%
CAUTION
TSOELURANE
CHECK
AIRCAL.
Switching
In
AIR
every one second.
If
the
[CAUTION/
CHECK
AIR
CAL]:
is
displayed,
perform
the
AIR
CAL
based
on
the
procedure
below:
AIR CAL. Procedure
1. Press the PUMP key and let it sample some fresh air.
2. When the indication becomes stable, stop the pump with PUMP key and prese the AIR CAL key
Q Caution
Before pressing the AIR CAL key, let the instrument sample enough fresh air. (ideally for 2
minutes. ) Otherwise, correct measurement cannot be performed,
A Caution
Whenever measurement starts, confirm if the AIR CAL value is displayed after fresh air is
sampled enough. If the AIR CAL. Value is not indicated (or even if [AIR CAL CAUTION] is not
displayed), perfrom the AIR CAL procedures by correct method.

2-7.
Affection
on
Measurement
from
Pressure
A CAUTION
The
pressure
in
the
Gas
Chamber
becomes
different
from
the
atmospheric
pressure
while
sampling
the
gas.
As
a
result,
the
indication
is
not
accurate.
Or,
if
an
instant
pressure
change
occurs
in
the
Gas
Chamber
or
the
Reference
Chamber,
the
indication
might
go
wrong.
(If
these
symptoms
occurs,
perform
the
AIR
CAL
right
away.)
Therefore,
take
care
about
the
following
points:
> Do not plug the GAS IN or GAS OUT while gas is feeding.
> Keep the pressure of GAS IN, GAS OUT, and REF. OUT equal to the atmospheric pressure
when the indication is read.
> Read the indication after the gas flow stops.
A CAUTION
When concentration change occurs suddenly on the FI-21, correct reading cannot indicate.
Absorption tube is not only for removing the humidity, but also for stabilizing the temperature of
the sampling gas. Therefore, equip an absorption tube on the GAS IN whenever the
measurement is performed.

3.
SETTING
MODE
(ENTER
+
POWER)
The
SETTING
MODE
is
for
“Change
the
Measuring
Gas”,
“Adjusting
the
Time”,
and
“Confirming
the
Saved
Data”.
You
enter
the
SETTING
MODE
by
pressing
the
POWER
key
while
the
ENTER
key
is
being pressed.
Once
you
enter
the
mode,
the
display
on
the
right
shows
up.
Move
the
cursor
(black
bar) by
W
A
keys
and
select
the
item
which
you
would
like
to
setup.
Go
into
the
item
by
[ENTER
key].
Items to Setup and the Contents
gra 12:00
| SELECT GAS
SET DATE/TIME
VIEW SAVED DATA
CLEAR SAVED DATA
Initial Display in Setting Mode
SELECT GAS Changing the measuring gas, the base gas and the output.
SET DATE/ TIME Adjusting the clock
VIEW SAVED DATA Confirming saved data
CLEAR SAVED DATA Clearing the saved data
START MEAS. Starting the Measuring Mode.
3-1. Changing the Measuring Gas (SELECT GAS)
Choose the measuring gas by the [W A] key and presse ENTER key to fix the choice. On the 1*
line, a sentense “IS SETTING OK?” apperears. Press [ENTER] key again if it is okay. If you want to
change the setting, press the [CANCEL] key.
a 12:00 12:00
SETTING NO. 1 TERE
HALOTHANE ENTER CH4
in
AIR
[ENTER
in
AIR
0. 00—6. OOvol%
Select by W A keys.
0. 00-6. 00v01%
If the setting is what you
intend, press the ENTER key
to save the setting.

11
3-2. Adjusting the Time (SET DATE / TIME)
Initial
position
of
the
cursor
is
on
MONTH.
Choose
by
VA
ma
12:00
keys
and
fix
the
setting
by
the
ENTER
key.
The
cursor
then
DATE
moves
to
DAY.
Set
DAY,
YEAR,
HOUR
and
MINUTE
by
the
MANS
30
2001
same
procedures
as
MONTH.
HOUR
is
displayed
by 24
hour
to
00
clock.
3-3. Confirming the Saved Data (VIEW SAVED DATA)
On the 1* line, the data number is shown. On the 2" to 3" line, the saved date/ time are displayed.
Select the date number by [W A] key and fix the selection by [ENTER] key. The saved data then
comes up. (At displaying the saved data, the measuring gas and the base gas is displayed with
white letters on black background.) (CANCEL key leads to the initial display in Setting Mode.)
вы
12:00
12:00
NO.
001
É
DATE:
JAN.
30
2001
4.
13
vol%
TIME:
16:32
HALOTHANE
Y
A+
ENTER
in
02
NO.
001
3-4. Clearing the Saved Data (CLEAR SAVED DATA)
Select the “CLEAR SAVED DATA” by VA key and em 12:00
AN
fix th lecti
x the selection by ENTER key. If you want to cancel CLEAR SAVED DATA
the action, select “CANCEL” and press the [ENTER]
key.
3-5. Start the Measurement ( START MEAS. )
If you want to start the measurement right after {aa 12:00
AN
tti h it lect “ if
settingeach
item,
select
“START
MEAS”
and
press
START
MEAS.
[ENTER] key. The diplay will then go to the Meauring
Mode.

12
4. Maintenance
4-1. Replacing the Batteries
À Warning
> All the C size Alkaline batteries used in the instrument should be same kind.
> Replace the 4 of the batteries at the same time.
1) Confirm that the power is off.
2) Take out the instrument from the carrying case.
3) Take off the battery cover under the bottom by turning the screw with a coin.
4) Take out the old batteries and put the new ones caring the polarities.
5) When the replacement is done, put the battery cover on the bottom by the opposite
procedures.
4-2. Confirming the Sensitivities
It
is
recommended
that
the
sensitivity
of
the
instrument
be
confirmed
periodically
(at
least
once
a
year)
to
assume
the
correct
operation.
The
procedures
for
the
sensitivity
confirmation
are
as
follows:
If
any
problem
is
found,
or
If
you
would
like
to
have
it
calibrated,
please
contact
any
of
our
agents.
1)
Select
“DESFLURANE
in
AIR
0-20vol%”
and
go
into
the
measuring
mode.
2)
Perform
the
AIR
CAL
as
it
is
done
for
the
usual
measurements.
3)
Feed
some
pure
CO2
(at
99.999%
+)
to
the
instrument.
4)
Perform
the
Air
Correction
by
the
following
calculation:
| . 101.3[ kPa ]
Result
of
the
Air
Correction
[vol%]
Atmosphere
Pr
고
Measurement [kPa]
X Indication Value[vol%]
5)If
the
result
of
the
Air
Correction
is
15.66+0.47[vol%],
the
sensitivity
is
normal.
4-3. Daily Check
1)
Is
there
any
damage
on
switches,
lamps,
display
or
body?
2)
Confirmation
of
battery
voltage.
3)
Do
you
see
“CAUTION
…"
or
"ERROR…"
during
the
operation?

6. Trouble Shooting
Trouble shootings mentioned below do not cover all the problems. The ones considered frequently
occur are simply indicated to help your research for cause and solution.
Symptoms
Causes Solutions
Power does not turn ON.
No batteries. Or, AC adaptor
is not connected.
Polarity of the batteries is
wrong.
Time to press the POWER
Key is short.
Put the batteries in. Or,
connect AC adaptor.
Put the batteries in correct
direction.
Keep pressing the POWER
key until the buzzer beeps.
Reading is not correct.
AIR CAL is not performed in
a correct way.
The selected “Measuring
Gas” or “Base Gas” is
wrong.
Interference gas is included
in the sample gas.
A sudden pressure change
occurs at GAS IN, GAS OUT
or REF. OUT.
The pressure at GAS IN,
GAS OUT or REF. OUT is
not
at
atmospheric
pressure.
When the instrument
samples enough fresh air,
stop the pump. Then, press
the AIR CAL key.
Select the correct
“Measuring Gas” and “Base
Gas”.
The target gas that contains
interference gas cannot be
measured.
Perform AIR CAL again.
Set GAS IN, GAS OUT and
REF. OUT under the
atmospheric pressure.
though any gas is not fed.
After performing AIR CAL,
the reading goes up even
Molecular
attached
to
the
chamber
inside
or
tubing
inside
starts
detaching.
The
concentration
in
chamber
becomes
high
in
fact.
Let the instrument sample
enough fresh air. And
confirm if it shows the AIR
CAL value.
13

7. Caution on Usage
The
following
caution
items
must
be
followed
to
maintain
the
performance/
safety
of
the
instrument.
A Danger
>
Specification
of
this
instrument
is
based
on
a
non-explosion
structure.
Do
not
use
it
in
a
place specified as a hazardous area.
>
Make
any
solutions
for
exhaust
gas
emitted
from
GAS
OUT,
to
avoid
harmful
gas
from
emission.
(e.g.
Connecting
a
sampling
bag
to
GAS
OUT.)
>
Just
in
case
of
leaking
from
the
instrument
itself,
wearing
a
mask
and
gloves
is
recommended.
A Warning
> The instrument shows incorrect indication when it samples a high concentration gas over the
full scale.
> Use the batteries based on the specifications.
> Use the specified AC adaptor if necessary.
A Caution
> Do not use this instrument close to other apparatus that generates a strong noise, It may
affect the wave form of the power source. If the AC adaptor is applied, do not use the same
power source as other apparatus that generates a strong noise.
> Use the power source based on the specifications.
> Do not operate the instrument in a place which has a reaction heat such as infrared emitted
from high temperature. Or, Avoid a place which has a direct sunbeam that makes the
instrument over 35C.
> Interference Gas: The gases which are neither the target gas nor base gas.
If there is any interference gas in the measuring gas, the reading goes wrong. Do not measure
the gas which contains interference gas.
> Let GAS OUT and REF. OUT expose to the air, in order to equal the pressure inside to the
atmospheric pressure.
> Whenever this instrument operates, keep it in a carrying case and connect the absorption
tube.
14

8.
Defenition
of
Terms
vol%
Measuring Gas
Base Gas
Reference Gas
Gas Chamber
Reference Gas
Chamber
AIR CAL VALUE
The
rate
of
substance
occupying
in
some
volume. The
unit
is
indicated
by percentage.
The
target
gas
to
measure
in
the
sample
gas.
The
balance
gas
in
the
sample
gas.
The
gas
(fresh
air)
to
take
the
standard
refractive
index.
Chamber
that
is
filled
by
sample
gas.
Chamber
that
is
filled
by
reference
gas.
Concentration
indicated
on
the
display
when
AIR
CAL
key
is
pressed.
[Composition] [Operation diagram]
Parallel
mirror
Prism
LCD
display
Vaporizers
πι
42.
=
Gas
chamber
1.57
vol%
Л
i
i
HALOTHANE
Ll
Anesthesia
machine
Ref
chamber
D
in
02
x FI-21 A
Sampling
"T"
E
Gas
chamber
Image
|
to
outlet
=
signal
Image
analysis
A
5
=
concentration
FAL
Teflon
>
LED
Mirror
Lens Lens
CcD
calculation
END
tube
εσας
Image
sensor
CPU

9.
Specifications
9-1. Specifications
Model FI-21
Model
02 Base:
Halothane,
Isoflurane,
Sevoflurane,
Desflurane
Measuring Gas . .
Air Base:
Halothane,
Isofluran,
Sevoflurane,
Desflurane
Reference
Air
(Standard) Gas
Dimensions
145(H)
x
200(W)
x
80(D)
(mm)
Weight Approx. 2 kg
Power Source
C size Alkaline Battery (4 ea.), or AC Adaptor (Option)
Display Contents
Measuring Gas, Base Gas, Concentration, Time, etc.
The
number
in
(
)
is
the
minimum
displayable
digit.
[Unit:
vol%]
ae
Holothane
Isoflurane
Sevoflurane
Desflurane
Ai
0—6
0—8
0-10
0—20*
ir
Measuring
(0.01)
(0.01) (0.01)
(0.02)
Ranges
02
0—6
0—8
0—10
0
一
20*
(0.01)
(0.01)
(0.01)
(0.02)
*
The
gas
does
not
vaporize
easily.
Therefore,
the
concentration
may
not
be
able
to
reach
the
full
scale.
AIR
CAL.
Value
=
Indication
when
the
instrument
detects
the
fresh
air.
[Unit:
vol%]
a
Base
Gar
Measuring
925
|
Halothae
|
Isoflurane
|
Sevoflurane
|
Desflurane
(AIR
CAL.
Value)
Air
0.00 0.00 0.00 0.00
02 157
1.65
1.70
2.10
B
(Drifting Value)
Drifting value of indication which might be generated when the ambient
temperature changes +10°C. [Unit: vol%]
Base e Os Halothane Isoflurane | Sevoflurane | Desflurane
Air 0.09 0.09 0.10 0.12
02 0.09 0.09 0.09 0.12
Accuracy +(Reading — 4) x 0.03 + B
Operating Temp.
5~35°C, Below 80%RH
& Humidity
Battery Life Approx. 30 hours (when the pump works 50% of the total operating time.)
Outputs Data Logger, O~ 1VDC Analog Output
Data Logging | Concentration Reading with Month/ Day/ Year and Time
Function Maximum Recoding Number: Up to 100

17
9-2.
Standard
Accessories
1)
Carrying
Case
sens
Teach
2)
Absorption
Tube
(Calcium
Chloride
included)
«***
1
each
encena 1 each
3) Sampling! "T"
4)
Instruction
Manual
O
1each
5)
Sampling
Tube
1
each
9-3. Warranty
RIKEN
KEIKI
CO.,
LTD.
warrants
gas
alarm
equipment
manufactured
and
sold
by
us
to
be
free
from
defects
in
materials
and
workmanship
for
a
period
of
one
year
from
the
date
of
shipment
from
RIKEN
KEIKI.
Any
parts
found
defective
within
that
period
will
be
repaired
or
replaced
at
our
option,
free
of
charge,
FOB
factory.
This
warranty
does
not
apply
to
those
items
which
by
their
nature
are
subject
to
deterioration
or
consumption
in
normal
service,
and
which
must
be
cleaned,
repaired
or
replaced
on
a
routine basis. Such items may include:
a) Lamp bulbs and fuses
b) Pump diaphragms and valves
c) Absorbent cartridges
d) Filter elements
e) Batteries
Warranty
is
voided
by
abuse
including
rough
handling,
mechanical
damage,
operation,
alteration,
or
repair procedures not in accordance with instruction manual. This warranty indicates the full extent of
our liability, and we are not responsible for removal or replacement costs, local repair costs,
transportation cost, or contingent expenses incurred without our prior approval.
THIS WARRANTY IS EXPRESSLY IN LIEU OF ANY AND ALL OTHER WARRANTIES AND
REPRESENTATIONS, EXPRESSED OR IMPLIED. AND ALL OTHER OBLIGATIONS OR LIABILITIES
ON THE PART OF RIKEN KEIKI CO., LTD. INCLUDING BUT NOT LIMITED TO, THE WARRANTY OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL RIKEN
KEIKI CO., LTD. BE LIABLE FOR INDIRECT, INCIDENTAL OR CONSEQUENTIAL LOSS OR DAMAGE
OF ANY KIND CONNECTED WITH THE USE OF ITS ROCUCTS OR FAILURE OF ITS PRODUCT TO
FUNCTION OR OPERATE PROPERLY.
This warranty covers instruments and parts sold (to users) only by authorized distributors, dealers and
representatives as appointed by RIKEN KEIKI CO., LTD.
We do not assume the indemnification for any accident or damage caused by the operation of this gas
monitor and our warranty is limited to the replacement of parts or our complete goods.

10. Measuring Principle
Refractive index of gas mixture is determined by the kinds of the composing gases and the mixture
ratio. As long as the kinds of composing gases are known, the mixture ratio (concentration) can be
determined by measuring the refractive index.
The optic interferometer applied in the FI-21 displays “Interference Fringes” on the CCD. The
Interference fringes move proportional to refractive index. The amount of the movement is measured
by solution of the interference fringes on CCD with Fourier analysis. And the result is converted to the
refractive index.
Concentration can be displayed by adding some data like “measuring gas” and “base gas” to the
refractive
index
determined
with
high
accuracy.
Sensitivity
of
the
optic
interferometer
depends
on
the
length
of
the
chamber.
Since
the
length
of
the
chamber
is
physically
unchanged
by
elapsing
time,
the
high accuracy is maintained for a long time.
Optic Interferometer Sensor
18