Logika Technologies Inc. Model HMD-SM Operator’s Manual
Rev 2.1 Dec-
13
Web
:
www.logikatech.com
Phone
: 905-829-5841
Fax
: 905-829-8787
:
P a g e
| 4
100%
0
0.25 0.50 0.75 1 1.25 1.50 1.75 2 2.25 2.50 2.75 3 3.25 3.50 3.75
Si
Ge
PbS
Steel 1000℃
Steel 250℃
Wave length
(μm)
A
Figure 2.1 Spectrum
of steel emission and different photocells
Scanning System-
The HMD-SM uses a scanning optical bench that enables hot metal
detection across a broad angle of detection. The optical field is scanned using a rotating
drum of multiple mirror facets that reflect the energy from the hot metal target in the
scanning field to the PbS photocell, see Figure 2.2 for details. The infrared energy is
converted to an electronic signal by the PbS photocell, which is then processed by the
electronic circuit and changed to a logic signal for analysis and control purposes.
Figure 2.2: HMD-SM Scanning System
Vertical Scanning field-
The HMD-SM is manufactured with one of three vertical field angles
10, 30 and 50 degrees, selected at the time of purchase. This enables the sensor to cover
the entire process area but not scan beyond the process line where interfering sources of
infrared energy may be present.
