Page 159 - CITS - Electronic Mechanic - TT - 2024
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ELECTRONICS MECHANIC - CITS
Aviation lighting
Digital computers and calculators
Traffic signals and Burglar alarms systems
Microprocessors and multiplexers
Optical Communication
Indicator lamps in electric equipment
LED television
Vehicle head lamps, domestic and decorative illumination, street lighting.
LED STACKING:
To stack LED modules a corresponding substructure is required so that they can be easily stacked up and stand
statically secure. The LED stacking from EXACT offers a stable modular system that can be easily attached to the
various LED modules on the market.
Stack lights are used in similar applications to beacon lights/strobes, however the information they typically display
encompasses more machine/process conditions. Stack lights typically use inincandescent , LED or xenon-type
strobes as their illumination source.
Stack lights are generally columnar structures in a variety of shapes, placing colour-coded indicator segments
on top of one another in a “stacked” orientation. A stack light will typically have up to five differently coloured
segments to indicate various conditions on the machine or process.
Segments in any combination of (typically) red, yellow, green, blue or clear white are actuated independently and
are either off, steadily lit, or flashing.
Stack lights are passive devices that may be controlled directly by programmable logic controllers, distributed
control systems, PC control systems or hardwired to machine controls such as timers, sensors and latching
relays.
Function
Various size stack lights
Stack lights are used in a variety of machines and process environments; specific colour-coding is assigned by
the system designer.
Commonly used colour codes for machine state conditions include:
RED: Failure conditions such as an emergency stop or machine fault
AMBER: Warnings such as over-temperature or over-pressure conditions
GREEN: Normal machine or process operation
BLUE: External help request, where an operator might be requesting raw materials, scheduling or maintenance
personnel assistance
WHITE: User-defined conditions to a specific machine, often related to productivity monitoring
Optionally an audible alarm buzzer, typically in the range of 70-105dB, may be added to alert machine operators
to high priority conditions.
IEC60073 addresses machine state colour-coding & acoustic alerting, which can be applied to devices including
panel pilot lights & stack lights. Machine operator intervention is typically required in red and yellow machine
states, as these are normally errors or warnings. Manual intervention is possibly necessary in blue and white
conditions.
Applications:
Demonstration by technician in Colgate Palmolive of how the Andon Button works
Common applications include, but are not limited to:
Productivity monitoring (often rate-based machine output management with parts-per-hour displays). Uptime &
downtime monitoring (overall equipment effectiveness) is a very common use for these devices.
Warning indication and machine fault management
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CITS : E & H - Electronics Mechanic - Lesson 84 - 89