Elmo Rietschle VC Serie Instructions De Service page 8

4. Coupling (picture )
The coupling rubbers (k) are wearing parts and should be checked regularly. When the coupling rubbers are worn this can be detected by a knocking
sound when the vacuum pump is started.
Defective coupling rubbers can cause extensive damage and even in some extreme cases break the rotor shaft.
To check the coupling, stop the motor (m) and isolate. Remove the screws (s
should also be removed. Pull off the motor together with the motor side coupling half (q). If the coupling rubbers (k) are damaged remove the
circlips (l) from the coupling bolt (r) and exchange the coupling rubbers (k). Leave the spacer (p) in place, check the coupling bolts (r) for any wear
and replace if necessary. To replace, remove the circlip (l
washer (u) and exchange the coupling bolts.
Re-assemble in reverse order.
Trouble Shooting
1. Motor starter cuts out vacuum pump:
1.1 Check that incoming voltage and frequency corresponds with the motor data
plate.
1.2 Check the connections on the motor terminal block.
1.3 Pump is trying to operate against a closed exhaust.
Solution: Optional extra, soft starter (ZAD).
1.4 Incorrect setting on the motor starter.
1.5 Motor starter trips too fast.
Solution: Use a motor starter with a time delay trip (version as per IEC 947-4).
1.6 The vacuum pump or the lubricating oil is too cold.
1.7 The viscosity of lubricant is too high.
1.8 Oil mist eliminator elements are blocked or contaminated.
1.9 Back pressure on the exhaust pipework is excessive.
2. Insufficient suction capacity:
2.1 Inlet filters or meshes are obscured.
2.2 Suction pipe work is too long or too small.
3. Vacuum pump does not reach ultimate vacuum:
3.1 Check for leaks on the suction side of the pump or at the system.
3.2 Viscosity of lubricant incorrect.
3.3 Incorrect adjustment of the adjusting bolt (X).
4. Vacuum pump operates at an abnormally high temperature:
4.1 Ambient or suction temperature too high.
4.2 Cooling air flow is restricted.
4.3 Problem as per 1.7, 1.8 and 1.9.
5. Exhausted air contains visible oil mist:
5.1 Oil separator elements are fitted incorrectly.
5.2 Incorrect oil brand is used.
5.3 Problem as per 1.8, 1.9, 4.1 and 4.2.
6. Unit emits abnormal noise:
Note: A knocking noise from the rotor blades is normal when starting from cold, as long as it disappears within two minutes with increasing
operating temperature.
6.1 The coupling rubbers are worn (see under "servicing").
6.2 The pump cylinder is worn.
Solution: send your complete unit off for repair to the supplier or approved service agent.
6.3 The vacuum regulating valve (if existing) is noisy.
Solution: replace valve.
6.4 Blades are damaged.
6.5 Problem as per 1.6 and 1.7.
7. Water in lubricant i.e. Emulsification:
7.1 Pump pulls in water because of the application.
Solution: Fit water separators on to the vacuum side.
7.2 Unit handles more water vapour than the gas ballast is designed for.
Solution: Consult supplier for the provision of an increased gas ballast capability.
7.3 Pump operates only for a short time and does not reach normal operating temperature.
Solution: Run the pump with closed suction until the oil has been cleaned.
Appendix:
Repair on Site: For all repairs on site an electrician must disconnect the motor so that an accidental start of the unit cannot happen.
All engineers are recommended to consult the original manufacturer or one of the subsidiaries, agents or service agents. The address of the closest
repair workshop can be obtained from the manufacturer on application.
After a repair or before re-installation, follow the instructions as shown under the headings Installation and Initial Operation.
Lifting and Transport: To lift and transport the vacuum pump the eye bolts on the pump and motor must be used. If an eye bolt is missing use suitably
rated strops. The weight of the pumps are
shown in the accompanying table.
Storage: VC units must be stored in dry ambi-
ent conditions with normal humidity. If a pump
needs to be stocked for a period longer than 3
months we would recommend to using an
anticorrosion oil rather than the normal lubri-
cant.
Disposal: The wearing parts (as listed in the
spare parts lists) should be disposed of with
due regard to health and safety regulations.
Spare parts lists:
E 233 ➝ VC 400 - VC 1300
) on the motor flange (n). For motors secured by the feet, screws (s
5
), pull off the coupling and fan (v) complete from the pumpshaft, remove the nut (w) with
1
VC
Noise level (max.) dB(A)
Sound power dB(A)
Weight (max.)
Length
Width
Height
Oil capacity
400 500 700
50 Hz 76 80 81
60 Hz 79 82 85
50 Hz - - -
60 Hz - - 97
kg 485 579 650
mm 1381 1517 1584
mm 931 986 986
mm 606 606 765
l 12 17,5 17,5
)
6
900 1100 1300
82 86 82
87 87 87
- 99 -
102 103 101
730 960 1050
1604 1763 1900
1083 1122 1122
805 805 805
20 26 26
10.06 / PM7