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Supplementary installation, operating and maintenance instructions English
Explosion-proof three-phase asynchronous motors with squirrel-cage rotor for high voltage
815001 Edition 09.2020
17
Maintenance work (except relubrication) must only be carried out when the machine is at a standstill.
It must be ensured that the machine is secured to prevent it from being switched on and has an ap-
propriate warning sign.
Furthermore, safety instructions and accident prevention regulations of the respective manufacturers must
be observed when using oils, lubricants and cleaning agents!
Adjacent parts that are live must be covered!
It must be ensured that the auxiliary circuits, e.g. standstill heating, are de-energized.
For the version with a condensation water drain hole, the drain plug must be coated with a suitable sealant
(e.g. Epple 28) before reclosing!
The work must be indicated by an additional repair sign with the following information:
Date
Firm carrying out the work
Type of repair, as appropriate
Identification of the officially authorised competent person within the meaning of the BetrSichV, as
appropriate
If the work is not carried out by the manufacturer, it must be accepted by an officially authorised
competent person within the meaning of the BetrSichV. That person must issue a written confirma-
tion of this or provide the machine with a test mark. In other countries, the relevant national regula-
tions must be observed.
9. Painting and impregnation after repair or maintenance work
When repainting explosion-proof motors or impregnating a complete stator after rewinding, thicker
layers of paint or resin may appear on the machine surface. (These can lead to electrostatic
charges, with the result that there is a danger of explosion if discharged.) Charging processes in
the vicinity can also lead to electrostatic charging of the surface or parts of the surface, and there
may be a risk of explosion due to discharge.
The requirements according to IEC/EN 60079-
0: “Equipment -
General requirements”, section 7.4 and TRGS 727 must therefore be strictly observed by taking the following
steps, among others:
Limiting the total paint or resin layer thickness according to the explosion group to
IIA, IIB:
Total coating thickness ≤ 2 mm
IIC:
Total coating thickness ≤ 0.2 mm
Limiting the surface resistance of the paint or resin used to
IIA, IIB, IIC, III Surface resistance ≤ 1GΩ for motors of group II and III
Disruptive discharge voltage ≤ 4 kV for explosion group III (dust only, measured by the thickness of the insu-
lating material according to the method described in IEC 60243-1).
Furthermore, the versions of E DIN EN
60079-
32: “Electrostatic hazards”, especially Annex A: “Fundamentals of static electricity”, Annex B: “Electro-
static discharges in special situations” and Annex C: “Flammability of substances” must be taken into ac-
count.
10. Storage / long-term storage (over 12 months)
For storage or outdoor use, a superstructure or appropriate cover is recommended. Avoid long-term expo-
sure to direct intense sunlight, rain, snow, ice or dust.
Long-term storage must be vibration-free in closed, dry rooms in a temperature range of -20 to +40°C and in
an atmosphere free from aggressive gases, vapours, dust and salts. The motors should preferably be trans-
ported and stored in their original packaging. Storage and transport on the fan guards is not permitted. Un-
protected metal surfaces, such as shaft ends and flanges, must be provided with long-term corrosion protec-
tion in addition to the temporary corrosion protection provided at the factory. If dew forms on the motors un-
der ambient conditions, precautions must be taken to protect them against moisture. Special packaging with
airtight welded film is then required or packaging in plastic film with moisture-absorbent substances. Pack-
ages of a moisture-absorbent material must be placed in the terminal box of the motors.
For transport, the eyebolts/load blocks of the motors must be used with suitable slings. The eyebolts/load
blocks are only intended for lifting the motors without any additional attachments such as base plates, gears,
etc.
Motors with reinforced bearings are supplied with a transport safety device. The transport lock on the shaft
end should only be removed when the motor has been assembled and before switching on.