Maintenance; Requirements; Visual Inspection; Cleaning - Siemens QUADLOG Installation And Service Instructions Manual

SDQLCAI-1

3 Maintenance

•
In potentially hazardous atmosphere, remove power from equipment before
connecting or disconnecting power, signal, or other circuit, or extracting/inserting
module.
•
Observe all pertinent regulations regarding installation in hazardous area.
•
Ensure all devices are rated for hazardous (classified) locations.
This section describes how to maintain the Critical Analog Input Module (CAI) and its associated wiring
termination assemblies. These items require minimal maintenance. Some routine maintenance is
recommended in the form of a visual inspection and possible cleaning. A module's operating status is
shown by light emitting diodes (LEDs) located on its bezel. Replacement procedures are provided for the
CAI and its associated wiring termination assemblies.

3.1 Requirements

The following tools are necessary for servicing:
•
Common electronic servicing hand tools
•
Digital multimeter

3.2 Visual Inspection

The CAI and its associated assemblies should be subjected to periodic visual inspection. The frequency
of inspection is dependent on the severity of the operating environment.
The primary aim of the inspection is to reveal any excessive accumulation of dust, dirt, or other foreign
material adhering to the surfaces of the Termination Strip and protective covers of the module.
Accumulation of dirt and dust prevents efficient heat dissipation and can contribute to module or system
failure. Refer to section 3.3 for cleaning instructions. Note that a CAI installed in a cabinet complying
with the NEMA (National Electrical Manufactures Association) 12/IP55 specification need not be
inspected for cleanliness.

3.3 Cleaning

Cleaning the CAI involves brushing or vacuuming the protective covers to restore cooling efficiency that
degrades by the accumulated dust, dirt, or other foreign materials.
May 2002
DANGER
Explosion hazard
Will cause death, serious injury or property damage
Maintenance
3-1