NORD Drivesystems B1091 - Manual (Page 16)

-16- B1091-GB-4613 www.nord.com
7. Motors for use in Zone 21 and Zone 22
according to EN 60079-0 and IEC 60079
7.3.1 Electrical Connection
The electrical connections of the terminal board are protected against twisting. The voltage supply to the
terminal board must be made by means of suitable ring terminals. The ring terminals are installed between
the two brass washers below the lock washer. The nuts must be tightened with a torque according to the
table below. The contact pressure is permanently maintained by means of the specified torque and the lock
washer. In addition, twisting of the ring terminals of the voltage supply is prevented. The connection
elements are corrosion-proof.
Torques for electrical terminal board connections
Nominal thread diameter Tightening torque [Nm]
M1.6 0.09-0.12
M3 0.35-0.5
M4 0.8-1.2
M5 1.8-2.5
M6 2.7-4.0
M8 5.5-8,0
M10 9.0-13.0
M12 16.0-20.0
M16 36.0-40.0
Electrical connection:
Brass nut
Lock washer
Brass washer
Brass washer
Brass nut
Brass washer
Ring terminal
Brass washer
Brass thread with collar
Mechanical protection against twisting
7.3.2 Cable and wiring glands
In Zone 21, the cable glands must be approved for Ex areas (protection class minimum IP 66) and must be
secured against accidental loosening. Unused apertures must be sealed with approved plugs (minimum
protection class IP 66).
For Zone 22, the cable glands must at least correspond to the protection type specified on the name plate.
Unused openings must be closed with plugs, which as a minimum correspond to the protection class of the
motor and the requirements of EN 60079-0 and IEC 60079-0. The cable glands and blank plugs must be
suitable for a temperature of at least 80°C.
The motor must not be opened under hazardous atmospheres for connection of the electrical cables or for
any other work. The voltage must always be switched off and secured against being switched on again
before opening the motor!
The motors are equipped with cable glands according to the following overview.
A
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