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Adrianh in reply to you query
In the current wiring code, reference to the standard test finger is made four times.
Fundamental requirements
Clause 5.1.1 Live parts
“It shall not be possible to touch any live part within arm’s reach with the standard test finger (SANS 60529/IEC 60529/SABS IEC 60529)”
Wireways
Clause 6.5.1.1 (k)
“Where it is accessible to the public, protection shall be such that it is not possible to touch any live parts with either the standard jointed test finger or the 2,5 mm diameter 100 mm long rod (see SANS 60529/IEC 60529/SABS IEC 60529). This protection also applies after opening any door or cover that can be opened without the use of a tool or key; ..”
Bathrooms, showers, spa’s, etc.
Table 7.1 Conditions under which electrical equipment may be installed in a bathroom
“B1 denotes that the equipment shall be so enclosed in insulating material that it is not possible to touch current-curing parts with the standard test finger;..”
Explanation of IP ratings
Annex J - Table J.1 - International protection ratings – IP ratings
If you look at the first section under “Protection against solid foreign objects”, IP 2, the following appears:
“Full penetration of 12,5 mm diameter of sphere not allowed. The Jointed test finger shall have adequate clearance from hazardous parts.”
The importance
From the SANS 10142-1 2003 Wiring Code the importance of such a test during installation and/or construction of electrical apparatus and the testing of electrical installations, this test is clearly very important.
How it’s done
This test simulates contact with live parts by a finger. It is done by using a metallic standard test finger, connected by an incandescent lamp or buzzer to one pole of a supply of least 40 V, while the other pole of the supply is connected to the parts intended to be live in normal service. The poles must be electrically connected together. The protection is deemed satisfactory if the lamp does not light or the buzzer does not buzz when an attempt is made to touch the bare or insufficiently insulated live parts with the test finger. The finger must be placed in every possible position and pushed without undue force.
Note: Conducting parts covered only with varnish or deemed to be enamel or protected by oxidation or by a similar process are insufficiently insulated. Such parts should, for the purposes of the test, be covered with metal foil that is in contact with parts that are alive in normal services.
In the current wiring code, reference to the standard test finger is made four times.
Fundamental requirements
Clause 5.1.1 Live parts
“It shall not be possible to touch any live part within arm’s reach with the standard test finger (SANS 60529/IEC 60529/SABS IEC 60529)”
Wireways
Clause 6.5.1.1 (k)
“Where it is accessible to the public, protection shall be such that it is not possible to touch any live parts with either the standard jointed test finger or the 2,5 mm diameter 100 mm long rod (see SANS 60529/IEC 60529/SABS IEC 60529). This protection also applies after opening any door or cover that can be opened without the use of a tool or key; ..”
Bathrooms, showers, spa’s, etc.
Table 7.1 Conditions under which electrical equipment may be installed in a bathroom
“B1 denotes that the equipment shall be so enclosed in insulating material that it is not possible to touch current-curing parts with the standard test finger;..”
Explanation of IP ratings
Annex J - Table J.1 - International protection ratings – IP ratings
If you look at the first section under “Protection against solid foreign objects”, IP 2, the following appears:
“Full penetration of 12,5 mm diameter of sphere not allowed. The Jointed test finger shall have adequate clearance from hazardous parts.”
The importance
From the SANS 10142-1 2003 Wiring Code the importance of such a test during installation and/or construction of electrical apparatus and the testing of electrical installations, this test is clearly very important.
How it’s done
This test simulates contact with live parts by a finger. It is done by using a metallic standard test finger, connected by an incandescent lamp or buzzer to one pole of a supply of least 40 V, while the other pole of the supply is connected to the parts intended to be live in normal service. The poles must be electrically connected together. The protection is deemed satisfactory if the lamp does not light or the buzzer does not buzz when an attempt is made to touch the bare or insufficiently insulated live parts with the test finger. The finger must be placed in every possible position and pushed without undue force.
Note: Conducting parts covered only with varnish or deemed to be enamel or protected by oxidation or by a similar process are insufficiently insulated. Such parts should, for the purposes of the test, be covered with metal foil that is in contact with parts that are alive in normal services.
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