IEC 61557-12-2021 Electrical safety in low voltage distribution systems up to 1 000 V AC and 1 500 V DC – Equipment for testing, measuring or monitoring of protective measures – Part 17: Non-contact AC voltage indicators.
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61 557-1 and the following apply.
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3.1 non-contact AC voltage indicator
hand-held and battery-powered probe without direct contact with the live part, indicating the potential between the live part and the human body, which is usually close to the earth potential
3.2 protective fingerguard
part of the enclosure that indicates the limit of safe access and reduces the risk of the operator touching hazardous live parts
[SOURCE: IEC 61 01 0-031 :201 5, 3.1 .3]
3.3 sensitivity range
range of voltage where the non-contact AC voltage indicator is triggering
4 Requirements
4.1 General
The requirements of IEC 61 557-1 :201 9, Clause 4 and the following requirements apply.
4.2 Influencing quantities – Operating uncertainty (B), percentage operating uncertainty (B [%])
IEC 61 557-1 :201 9, 4.2 does not apply.
4.3 Rated operating conditions
The following rated operating conditions shall apply:
a) ambient temperature range from: −1 0 °C to +45 °C;
b) maximum relative humidity 95 % at temperatures up to 31 °C, decreasing linearly to 50 % relative humidity at 45 °C;
c) distance through air between live conductor and probe tip: ≤ 2 mm;
d) position within a solid angle of 30° around the vertical axis between probe tip and conductor;
e) capacitance greater than or equal to 1 00 pF between the hand-held part and reference earth, see Figure 2.
4.4 Battery test facility
In addition to IEC 61 557-1 :201 9, 4.4, the following applies.
Non-contact AC voltage indicators shall have a self-test capability. As a minimum, the self-test function shall confirm correct operation of the batteries and of the voltage indication.
4.5 Safety
The requirements in accordance with IEC 61 557-1 :201 9, 4.5, do not apply. The following requirements shall apply instead.
All electrical safety aspects are covered by IEC 61 01 0-031 .
The hand-held parts of the non-contact AC voltage indicator and the probe tip shall be separated by a protective fingerguard, see Figure 1 .
The clearance and creepage distance between the outmost tip of the probe and the hand-held part of the fingerguard shall fulfil the requirements for double or reinforced insulation in
accordance with IEC 61 01 0-031 .
The probe tip shall be insulated by double or reinforced insulation from the handheld parts. The insulation shall fulfil the relevant requirements of IEC 61 01 0-031 .
Non-contact AC voltage indicators shall be designed for measurement category III at a minimum and for a minimum rated voltage to earth of 300 V.
The design of the protective fingerguard shall fulfil the requirements of IEC 61 01 0-031 .IEC 61557-12 pdf download.