Replacing The Protection Sensors - Grundfos S Series Service Instructions Manual

Connecting the new cable - metal cable entry (non-Ex/Ex)
To prepare a new cable (length of leads, cable clips,
cable markings, etc.), please use the old cable as
reference.
1. Measure (K) the outer diameter of the cable (181) and the
hole diameter (cable ID) from the motor top cover (164a).
Check the number of washers (185) needed, if any, in the
table below.
Cable [mm]
Cable ID
[mm-ver.]
min. max.
14.4 15.4
36-1
15.4 16.4
17.2 17.5
36-2 17.5 18.8
18.8 20.0
46-1 15.7 17.2
17.8 18.5
46-2 18.5 19.2
19.2 20.0
20.9 21.5
46-3 21.5 22.4
22.4 23.4
23.8 24.6
46-4 24.6 26.0
26.0 27.0
65-1 28.3 31.4
32.5 33.6
65-2
33.6 34.7
2. Slide cable entry (168) on the cable (181).
3. Fit the cable entry (168), washer(s) (185) and rubber seal
(198) on the cable (181).
4. Fit the cable entry to the motor top cover (164a) with screws
(181a).
5. Tighten the screws (181a) evenly to the torque specified in the
table above.
If a gap remains between the motor top cover and
cable gland/washer wait for 30-60 minutes and
retighten the screws.
6. Fit the cable clamp (180a) to the cable entry (168) with screws
(180a).
Connect according to the wiring diagrams.
16

9.2 Replacing the protection sensors

9.2.1 Moisture switch
The standard pumps have one moisture switch under the motor
top cover. The Ex pumps have two moisture switches, one under
the motor top cover and one in the stator housing. On Ex pumps
manufactured before February 2009, both moisture switches are
placed under the motor top cover
The changing method is the same, no matter where the switch is
placed.
Washer Torque
[pcs.] [Nm]
-
Checking the moisture switch
1
1. Connect the switch to a simple bell circuit or another test
0 10
1
2. Adjust the clearance between expander part and the switch
3
-
3. Remove the adjustment gauge.
-
Checking the microswitch
1 1. Connect the test bell or other test circuit.
2 2. Place the adjustment gauge between the expander part and
-
3. Pull the expander outward two to three times to make sure the
1
3 45
-
2
Adjusting the clearance of the moisture switch
1. Place the adjustment gauge between the expander part and
5
-
2. Pull the expander outward:
2
3
3. Remove the adjustment gauge
Install the switch and test the microswitch.
Do not touch the head of the moisture switch with wet
or oily hands. Moisture on the sensor head before
installation will cause false measuring values.
circuit.
body to 2.5 mm by using the adjustment gauge
the switch body.
that the bell stops ringing (the electric circuit will be broken)
when the expander is pulled outward and starts to ring when
the expander is free.
the switch body.
– If the bell rings, turn the adjusting screw clockwise until the
bell stops ringing
– If the bell is not ringing, turn the adjusting screw
counterclockwise until the bell starts ringing.
Spade connectors
Screw
Mounting bracket
Fig. 14 Moisture switch
Mounting screw
and lock washer