Stahl MT 7 Series, Operating Instructions Manual

Page: 25 / 44

Operating Instructions MT-xx7 Safety information
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R. STAHL HMI Systems GmbH / OI_MT_xx7_en_V_01_02_14.docx / 06.12.2019 Page 25 of 44
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The cable entries in the connection box must have ingress protection IP66 or may have to
be adapted to meet country-specific requirements. The pre-assembled cable entry threads
are:
- 2x M16x1,5
- 1x M20x1,5
- 3x M25x1,5
The wall of the terminal box where the cable entries are mounted has a thickness of at
least 4 mm.
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The cable connections must be tightened fast according to regulations. Unused cable
connections must be sealed with appropriate blind plugs. Only permanently laid cables
may be connected to the pre-mounted ATEX cable connections.
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The outer cable diameters must correspond to the cable connection specifications.
- Cable entry M16 for round cable, outside cable cross-section
4...8 mm (0.
16“...0.31“)
- Cable entry M20 for round cable, outside cable cross-section
6...12 mm (0.
24“...0.47“)
- Cable entry M25 for round cable, outside cable cross-section
14…18 mm (0.55"…0.71")
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The device must not be opened, maintained or repaired in hazardous atmospheres (sole
exception: the connection box) All circuits must be completely de-energised before the
device is connected. Before opening the connection box ensure that all circuits are
isolated. You must also ensure that the power supply circuit is isolated. The cable
diameter must meet the terminal specifications. The connection box must be tightly
sealed.
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The wire used for earthing must have a minimum cross section of 4 mm² ! Make sure that
there is equipotential bonding between the devices.
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We recommend you use screened cables with the device. Routing of the data cable may
reduce performance. The cables used in intrinsically safe circuits must have been tested
to AC 500 V / DC 750 V. If the cable properties are unknown, assume 200 pF/m and
1 µH/m.
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If display types MT-xx7-DVI1-MM or MT-xx7-DVI1-SM are used, terminal X16 remains
unused.
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To establish a secure earthed connection between device and plant and to prevent
inadvertent loosening of the cables, each cable with its screen must be connected to the
corresponding earthing bracket located in the Ex nA connection box close to the
associated terminal.
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At the place of installation voltage must not exceed 250 V and short-circuit current must
not exceed 1500 A.