NORD Drivesystems B1092 - Manual (Page 9)

www.nord.com B1092-GB -9-
5. Motors with increased ignition
protection, type "e" Ex e
In the case of external sources of heat or cold, no additional measures are necessary if the
temperatures of the attached components do not exceed the permissible temperatures listed
in Table 3. The values in Table 3 apply for an ambient temperature of -20°C to +40°C with
self-ventilation. Special applications with external sources of heat and cold must be examined
by means of type testing with regard to the effect on the maximum surface and operating
temperatures and suitable measures taken if necessary.
For the installation of electrical equipment in explosion hazard areas in Germany, attention is
drawn to DIN EN 60079-14:2003 and the "Betriebssicherheitverordnung" [Operating Safety
Regulations]! In foreign countries the appropriate national regulations must be observed.
Operation with an inverter must be explicitly certified. The separate manufacturer's information
must be observed.
5.1 Additional information for operation with a frequency inverter
In addition to this information, the operating instructions of the frequency inverter and if
necessary the operating instructions of the gear unit and any other operating instructions must
be observed. Failure to observe these can cause material damage and personal injury.
Series 1 MA7 motors are produced in the ignition protection type "Increased Safety" and are
suitable for operation with a frequency inverter. The suitability can be identified by the
statement of the maximum frequency (e.g. f
max
100 Hz) on the type plate.
Individual acceptance by a designated testing facility is not necessary.
It is essential that the supplied data sheet for the EU prototype certification (see
Section 7.) is complied with. This includes important information for operation and
commissioning.
Ex e motors suitable for use with frequency inverters are equipped with a triple PTC.
This must be evaluated by a certified triggering device with protection type labelling Ex II (2)
G.
The joint operation of several motors on one frequency inverter is not permissible.
Connecting cables must be dimensioned for a continuous thermal load of at least 80°C.
In addition, the frequency inverter used must be equipped with a speed-dependent current
limitation (Precision of measurement of effective current: 5%).
The current limitation is set to the maximum permissible nominal current of the
frequency inverter. A limitation of the output current of the frequency inverter to double the
rated current of the motor must be ensured.
Observation of the rev/f characteristic and the permissible torque depending on the
frequency is essential.
Voltage drops due to the use of long supply cables and/or sine wave filters between the
motor and the frequency inverter must be taken into account. The maximum
permissible length of cable is 30m. The frequency inverter also causes a drop in
voltage.
The motor terminal voltage can be influenced by increasing the input voltage of the frequency
inverter.
Voltages in excess of 1556 V (peak values) must not occur at the motor terminals.
Unfavourable cable lengths and short switching times of the frequency inverter can
cause impermissible overvoltages. The occurrence of such overvoltages must
be ruled out before starting up.