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In the event of subsequent repairs, the existing plate must be
replaced by a new, updated one and earlier markings must be
recorded.
The repair workshop must keep records of all the previously
performed overhauls, repairs and possible modifications.
Copies of the detailed records of the repairing workshop must be
filed by the owner or operator with the original type certificate of the
explosion-proof motor.
8.1.1 Power cable
Use manufacturer-approved and compatible cables only.
8.1.2 Cable entry
Use only Ex cable entry parts corresponding to the cable diameter.
The correct cable dimension marking is stamped on the inlet or the
cable entry.
8.1.3 Spare parts
Damaged motor parts must always be replaced by new and
approved parts. Motor parts must not be reconditioned.
8.2 Mechanical tightness test
The purpose of the mechanical tightness test is to ensure that the
seals in the seal housing are functioning properly after a motor
reassembly. If a motor fails this test, water enters the motor
compartment once the pump is back in operation. The test
procedure is the same for both SE and SL, however, the inlet
connection point for the pressurised gas is different with SE and SL.
This test is not able to determine the condition of the shaft
seal.
Attachments, hoses, etc, used to conduct this test need to be
sourced locally.
Test procedure:
•
Test the motor once it is assembled, but before the motor liquid
is filled.
•
Pressurize an inlet test pipe with dry pressurised air or nitrogen
gas, 0.6 - 0.8 bar (8.7 - 11.6 psi) (max) connected to Connection
Point A, and place the end of the outlet test pipe from
Connection Point B slightly under water.
•
Rotate the shaft manually a few times and carefully monitor for
at least 2 minutes. If air bubbles are coming from the test outlet
tube, it indicates leakage. In case of leakage, re-open the motor,
and make sure the root-cause is identified and eliminated.
A
Mechanical tightness test connection points - SL
14
B
A
Mechanical tightness test connection points - SE
8.3 Motor liquid check and change
Clean the outside of the pump regularly to retain the heat
conductivity.
Change the motor liquid once a year or after 2000 operat-
ing hours to prevent oxidation.
Lack of motor liquid may cause overheating and damage
to the mechanical seals.
Use SML3 coolant for motor cooling.
8.3.1 Refractive index
The refractive index can indicate the leakage of the pumped liquid
into the motor liquid (propylene glycol). Use a refractometer
(product no 98676968) which shows the refractive index in percent.
Always use the propylene glycol scale.
Measured freezing point
-20 °C (-4 °F)
-18 °C (0.4 °F)
-17 °C (1.4 °F)
-15 °C (5 °F)
-14 °C (6.8 °F)
If the refractive index has a freezing point greater than, or equal to
-14 °C (6.8 °F), the motor liquid must be changed. If the liquid
ingress level is higher than 20 %, change the motor liquid.
Drain the leakage chamber of the pump after 2000 operat-
ing hours.
Check the freezing point of the new glycol prior to use, to
ensure that the freezing point is -20 °C (-4 °F).
B
Liquid ingress percent (%)
0
5
10
15
20
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