Grundfos MGE 100, Instructions Manual

English (GB)

6

6. Megging

1. Disconnect the power supply.
2. Remove the terminal box. See section 

7.9 Replacing the 

terminal box

.

3. Measure between terminals T1, T2, T3 and earth. As windings 

are star-connected, fault in a winding will show when 
measuring all terminals.

4. Replace the entire motor unit in case of fault. See also 

measurement of winding resistances in section 

9.4 Power 

module

.

5. Fit the terminal box. See section 

7.9 Replacing the terminal 

box

.

6. Switch on the power supply.
7. Start the pump.

7. Replacing hardware

Fig. 1

Antistatic service kit

7.1 Replacing the terminal box cover

1. Loosen the four screws (251d) and remove terminal box cover 

(251b).

2. Clean the sealing faces of terminal box (251a) and the 

terminal box cover.

3. Fit the terminal box cover and cross-tighten the screws. Make 

sure that the position of the terminal box cover is correct in 
relation to the control panel (290).

7.2 Replacing the battery

Applies only to the FM300 functional module.
1. Disconnect the power supply.
2. Remove the terminal box cover. See section 

7.1 Replacing 

the terminal box cover

.

3. Insert a screwdriver under the battery (273b) and prise the 

battery out of the isolation cover (277).

Fig. 2

Removing the battery

4. Insert the new battery with the positive pole upwards.

5. Press the battery home with a finger.
6. Fit the terminal box cover. See section 

7.1 Replacing the 

terminal box cover

.

7.3 Fitting the antenna

1. Disconnect the power supply.
2. Remove the terminal box cover. See section 

7.1 Replacing 

the terminal box cover

.

3. Remove the blanking plug (252b) from the terminal box.
4. Fit the union (291) in the terminal box.
5. Lead the antenna into the union from above and tighten the 

top part (close to the wire).

6. Click the antenna wire onto the control panel (290). The 

antenna wire is long enough to be fitted in both positions of 
the control panel.

7. Fit the terminal box cover. See section 

7.1 Replacing the 

terminal box cover

.

An installation with MGE motors must not be megged 
as this may damage the built-in electronic parts.
Motor windings may, however, be megged if the 
terminal box has been removed.

Never measure between two terminals.

Max. test voltage

Max. leakage current [mA]

1000 VAC/1500 VDC

35

Always use an antistatic service kit when handling 
electronic components. This will prevent static 
electricity from damaging components.
When unprotected, the component must be placed 
on the antistatic cloth.

TM

05 159

0 321

1

The control panel can be turned 180 °.

The old battery must be disposed off according to the 
battery directive (2006/66/EC).

T

M

05

 70

21

 04

13

The new battery must comply with the battery 
directive (2006/66/EC).

Make sure that the antenna wire is not sharply bent 
or pinched when you fit the terminal box cover.