-Remove one item of each family of items in the area that has
contamination.
-Clean the surface of the item.
-Examine the item to know the type of contamination: . Surface contamination: the contamination agent does not go into the item. . Deep contamination: the contamination agent goes into the item. In this condition, we strongly recommend that you replace the item.
R ____
NOTE : If there is a risk of a new contamination, you can replace a R non-sealed item by a sealed item.
__________________
3.
Safety Precautions If you disconnect and connect an electrical line, you must do a continuity test and an insulation test to make sure that the circuit operates correctly. Make sure that all the areas that you cleaned are dry before you energize the electrical circuits.
_____________________________________________________
4.
Connectors, Terminal Block Modules, Grounding Modules
A. Sealed Items
____
NOTE : Do not disconnect the sealed connectors, the terminal block modules or the grounding modules.
In the areas where there is risk of liquid contamination, the connectors or the terminal block modules are usually sealed. In these areas:
-do not move the wires in the cavities.
-apply the solvent as a spray on the item.
-let the solvent operate then dry with a clean cloth.
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B. Non-Sealed Items
This procedure will be issued later.
________________5. Relays and Bases
A. Relays
(1)
Surface contamination
Do not disconnect the relay from its bases
-Apply solvent with a brush.
-Let the solvent operate.
-Dry with a clean cloth.
(2)
Deep contamination We recommend that you replace the item. If your decision is not to replace the item, do these steps:
-disconnect the relay.
-clean the face and the contacts with solvent applied with a brush or with a cloth.
-let dry.
-connect the relay.
B. Bases
(1)
Surface contamination Do these steps only if there is no risk that the solvent will go in the cavities:
-do not disconnect.
-apply the solvent with a brush.
-let the solvent operate.
-dry with a dry cloth.
(2)
Deep contamination
This procedure will be issued later.
___________________________
6. Pushbutton Switches, Lights You must replace an item that has contamination because contamination on its movable contacts will cause incorrect operation.
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Apr 01/02
R
________
7. Switches
Use a cloth moist with solvent or a brush to clean the sealed items with
grommets.
Replace the non-sealed items.
________________
8.
Circuit Breakers You must replace an item that has contamination because you cannot be sure that the contamination agent did not go into it.
__________________________________________
9.
Terminals (Terminal Strips, Ground points)
-Do not release the connections. The tightening torque initially applied makes the connections sealed and gives protection against deep contamination.
-Use a vacuum cleaner or a cloth to remove the contamination.
-Clean with a dry cloth or a cloth moist with solvent. If you use solvent, let it operate during 10 seconds then dry with a dry cloth.
-Put a new identification if necessary.
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