SC-IRDA Infra-red Communications Interface
3
FIGURE 1. SC-IRDA Sensor Installed in a Standard Enclosure
If mounting the SC-IRDA in this way, you need to consider several factors to
ensure ideal placement of the interface. The final installation position needs to
allow you to hold your computer in an acceptable position such that you can
use it comfortably whilst pointing it at the sensor at the end of the SC-IRDA
interface. Ideally the two IRDA sensors should point at each other "head-on".
Exposure of the sensor to the weather is not normally a big problem as the
SC-IRDA is sealed against moisture. However, the sensor lens may degrade if
exposed to wind blown sand or ice. Deposits of dust or rain on the sensor can
normally be gently wiped off with a soft cloth before communication is started.
Exposure of the sensor to bright sunlight may reduce the maximum spacing
between computer and the interface. Exposure to strong artificial lights which
have a high frequency electronic ballast may also reduce the working range. In
addition they may cause the SC-IRDA to stay “awake” and thus draw 5mA
continuously.
The bottom of an enclosure provides a little extra protection from both the
weather and direct light, but is not practical if the enclosure is mounted at a low
level.
For installations where the enclosure is mounted in an inaccessible position,
high up a tower for example, the serial cable can be extended by up to 10
meters. The rear of the interface is sealed to the same standard as the sensing
IRDA Sensor fitted to enclosure
using a high-quality cable gland
(cord grip).
