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ATEX-IECEx - Installation Instructions

ATEX-IECEx Installation Instruction

The ATEX - IECEx Directive besides taking into account the electrical sources of explosion, also considers potentially explosive concentrations of gas, vapor or mist along with dust in the air.
Note: When specific ATEX - IECEx / AEX / In Metro approved Terminal Blocks are required, please specifically mentioned this in your purchase orders. Such orders will be processed with due consideration.
Connectwell Terminal Blocks having ATEX - IECEx approval will be marked as follows:

Condition of Safe Use – increased safety "e"
The Terminal Blocks are suitable to mount on DIN35/ DIN32/ DIN15 as applicable.The Terminal blocks are suitable for use in ATEX / IECEx certified enclosure with minimum IP rating of IP 54.The terminal block has to be built into the enclosure with the type of protection "t" (complying with IEC/EN60079-31)" standard when placed in dust atmosphere. The terminal blocks are suitable for maximum service temperature 85°C, considering the self-heating when used at rated current with specified maximum conductor size & at ambient temperature range of -40°C to +40°C at mounting position.
When the Terminal Blocks are used in electrical apparatus, the highest temperature of the insulating material shall not exceed the max value of the temperature 85 °C.
When these terminal blocks are mounted, the minimum creepage and clearance distances shall be maintained for respective voltage rating, withneighboring terminal blocks. Proper care should be taken for stranded wire type of connection in terminal blocks, so that conductors do not get damaged while installation.
Installation instruction - Intrinsic Safety “i”
IEC/EN 60079-14 Clause 12 states Modular Terminal Blocks as simple apparatus when used in intrinsically safe circuits. Testing by a notified body and marking is not required. If Terminal Blocks are identified as part of an intrinsically circuit are marked by a colour, the colour used shall be light blue. Testing for compliance to intrinsically safe requirements including clearance, creepage, and solid insulation distances specified in IEC/EN 60079-0 and IEC/EN 60079-11 have been performed for circuits up to 60 V. Compliance with distance requirements of IEC/EN 60079-14 Clause 12.2.3 for the connection of
separated intrinsically safe circuit accessories is met. A minimum distance of 50 mm to separate clamping units of intrinsically safe and non-intrinsically safe circuits is required by using a partition plate or spacer or similar device.
Schedule of Limitations:
1) When these terminal blocks are mounted, the minimum creepage and clearance distances with neighbouring terminal blocks
and between the current bar & DIN-Rail shall be maintained as per the table given below:-

2) To avoid the risk of short-circuits between adjacent conductors in terminal blocks; the insulation of each conductor shall be maintained
up to the metal of the terminal.
3) All terminal screws and nuts used shall be tightened down wherever applicable as per the torque values specified in the table on page 2.
4) When this product is intended to be used in a potentially explosive dust atmosphere, it shall be installed in an enclosure that is suitably certified for use in that environment.
5) The housing material of the terminal blocks is not rated for UV protection. The terminal blocks are not to be installed in an enclosure with a glass or transparent plastic window or cover unless suitable protected against direct sunlight.
6) When used in intrinsically safe circuits, the terminals shall not be used for voltages above 60 V peak.
7) Where the terminals of intrinsically safe and non-intrinsically safe circuits are in the same enclosure, measures shall be taken to maintain at least 50 mm separation, using a spacer or similar device. Alternatively, a partition meeting the requirements of the relevant code of practice (e.g. IEC 60079-14) shall be used.
8) When used as part of an intrinsically safe circuit, terminal blocks shall meet the requirements for a T4 temperature class at 85°C ambient.
9) When the device is mounted in a hazardous area, connection and disconnection of the device from the rail while live is only permitted if the potentially explosive atmosphere is shown to be absent. This restriction does not apply if the circuit is intrinsically safe.
10) When used as part of an intrinsically safe circuit, terminal blocks shall be marked with a light blue colour or otherwise indicated that the
circuits are intrinsically safe.
For Fuse & Disconnecting Terminal Block
11) The supply must be switched off before lifting the fuse carrier from base terminal. (Do not actuate the disconnecting knife or fuse carrier when energized). Do not replace or remove the fuse when energized.
12) Fuse terminals: The replacement fuses shall be, either FSF series manufactured by Schurter, or PSF series manufactured by Protectron. The size of the fuse is Ø 5 X 20mm. The fuse shall be selected so that it is used within the manufacturers' ratings: breaking capacity, rated current and voltage rating. The rated current shall not exceed 6.3A.
13) Fuse terminals: The fuse shall not be removed or replaced when energized.
14) Ex ic fuse terminals shall only be mounted inside a suitably-certified flameproof enclosure.
15) Disconnect terminals shall only be operated when the circuit is electrically isolated. This restriction does not apply if the circuit is intrinsically safe.
16) Fuses shall be marked either as increased safety or intrinsically safe, but not both. Terminals that are marked as intrinsically safe shall be light blue.