METIS M311 / M322 / H311 / H322 (17-pin)
Mechanical Installation
19
5.6.2 Focusable Fiber-Optic Lenses
25 mm Optics
Model
Temperature ranges
[°C]
M322:
300-1000°C
H311:
FSC <1500°C
H322:
FSC <1200°C
M311/ M322:
all
other temp. ranges
H311:
FSC
≥
1500°C
H322:
FSC
≥
1200°C
Meas. distance a [mm]
Spot size diameter M [mm]
M311 / H311:
OQ25-B1
M322 / H322:
OQ25-B2
240
2
1
300
2.5
1.5
400
3
2
500
3.7
2.5
600
4.5
3
700
5.2
3.5
800
6
4
1000
7.7
5
1500
11.5
7.5
2000
15.4
10
2500
19.2
12.5
3000
23
15
Aperture diameter D: 10-13 mm
Fiber Ø 0.4 mm
Fiber Ø 0.2 mm
Measuring distance
a [mm]
Spot size diameter M [mm]
12 mm Optics
OQ12-C0
120
2.2
1.2
150
2.8
1.5
200
3.8
2
250
5
2.5
300
6.3
3.4
350
7.5
4
400
9
4.7
500
12
6
Aperture diameter D: 5-7 mm
Fiber Ø 0.4 mm
Fiber Ø 0.2 mm
(D is dependent on the optics pull-out: optics pulled out: higher value, optics inserted: smaller value)
FSC = Full scale temperature
5.6.3 Calculation of the Spot Size Diameter outside the Focused Distance
The spot size diameter determines the area on the measurement object from which 90% of the temper-
ature radiation is detected by the pyrometer; therefor the spot size tables specify spot sizes for different
measuring distances (or focused distances). For calculating intermediate values in front of and behind
the focused measuring distance, the following formula can be used or the spot size calculator integrated
in
SensorTools
a
Focused distance
M
Spot size diameter in the focused measuring
distance
a
1
Measuring distance longer than focused
measuring distance
M
1
Resulting spot size on measuring distance a
1
a
2
Measuring distance shorter than focused
measuring distance
M
2
Resulting spot size on measuring distance a
2
D
Aperture (specifies the spot size directly on
the optics lens, it differs depending on the optics pull-out. The largest value applies at a fully ex-
tended optics, the lowest value is with inserted lens)
OQ12
OQ25
M
M
2
M
1
a
2
a
a
1
M
1
= (M+D)-D
a
1
a
M
2
= (M-D)+D
a
2
a