Dna-Ex - Dnb-Ex; Replacing The Power Cable; Lower Mechanical Seals Replacing; Tools - DRENO Compatta PRO Manuel D'utilisation Et D'entretien

A) Unscrew the 3 socket head screws that connect the pump body with the motor casing.
B) Now, extract the pump body from the motor casing.
C) Using a wrench, unscrew the self-locking nut that fastens the impeller.
D) The impeller should now easily remove from the motor shaft.
Before fitting a new impeller, pay attention that the end of the shaft is clean and has no imperfections.
12 .5 DNA-EX - DNB 80-EX
A) Unscrew the four screws that connect the motor casing to the body pump.
B) Unscrew the four screws that connect body pump to closing plate and remove the closing plate.
C) Keeping the impeller blocked, unscrew the hexagonal head screw or the self locking nut, which connect it
to the motor shaft.
D) Unscrewing this screw or nut, you can easily remove the impeller. Before mounting a new impeller, pay
attention that the terminal part of the shaft is clean and without imperfections.

13 . Replacing the power cable

• Check that the power supply is disconnected and that the pump cannot restart,
not even accidentally, before starting to work on it.
• The electric pump can only be disassembled by DRENO POMPE qualified personnel,
taking care to handle the pieces with work gloves
A) Disconnect the connection between the motor wires and those of the cable to be replaced
B) Loosen the screws that lock the clamp to the cable
C) Unscrew the cable gland
D) Extract the washer and cable grommet
E) Insert washer, cable gromment, and a new cable gland to the power cable to be replaced.
For the ATEX H07RN8F cable the maximum diameter allowed is 12.3mm and a minimum of 11.3mm.
(Nominal diameter is 12mm).
F) Apply the connections
G) Screw the cable gland in with a tightening torque of 40Nm

14 . Lower mechanical seals replacing

The following operations should only be carried out by qualified DRENO POMPE engineers.
To replace the mechanical seal, carry out these operations in sequence.
A) Before replacing a mechanical seal, uncouple the impeller as indicated in paragraph 12.
B) Using two cutting screwdrivers, remove the old seal, first lever the rotating part and then the fixed ring,
paying attention to position the pump so that oil does not seep from the sump. (GX and AM-AT 50/2/110
C.225-226 solely)
C) Before fitting a new seal, ensure the housings are clean, free from burrs or grooves that could damage the
seal or in any case compromise the sealing to the shaft.
WARNING: It is advisable to avoid jamming, which may prejudice breakage of the fixed ring, after inserting
the fixed ring insert the rotating part of the seal.
D) For GX insert and fix the impeller fixing the screw UNI 5931 M5x50 A2 using a clamping torque of 9.5 Nm.
For AM-AT 50/2/110 C.225-226, COMPATTA PRO, ALPHA V PRO, BIC PRO, DNA -EX, DNB -EX insert the
impeller in the shaft paying attention to the key direction, tighten the self-locking nut by a torque of 9.5 Nm.

15 . Tools

The tools used exclusively by qualified DRENO POMPE engineers are:
• Allen keys: 4 - 5 mm
• Phillips screwdriver
• 2 cutting screwdrivers
• Hexagonal wrench: 8-17
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16 . Troubleshooting

If the electropump doesn't start, one of the following cases could be happened :
• There is no power supply (Check the fuses to see if they are burnt or if a circuit protec-
tion relay has tripped.);
• The selector is on OFF (select ON.);
• A phase is missing (Check the line connections);
• The impeller is blocked;
• The mechanical seal or ball bearing have seized.
If the user detects the electropump starts and stops too frequently it is extremely im-
portant to check the reason, that it could due to an incorrect use. Stop and re-start the
pump, if the above condition continues, it is necessary to address to a Service Centre or
put in touch directly with one of our skilled persons Dreno Pompe.
If the electropump works, but the flow rate is poor or non-existent, one of the follow-
ing cases could be happened:
• The direction of rotation of the pump is not correct (three-phase motors only);
• Check the wearing condition of the hydraulic part;
• The pumps is working inside an air pocket (stop the electropump and start it after a few
minutes, paying attention to carry out the hydraulic plant breathing);
• The delivery piping is clogged, the check ball-valves and/or gate valves are partly
closed;
• The pump works on and off;
• Check if one of the following conditions are present;
• Too hot liquid (higher than 40°C);
• Too cold liquid (lower than 0°C);
• The voltage supply is higher compared to the required limits (+/- 5%);
• The impeller/blades is clogged by an obstruction which prevent the right rotation;
• It is suggested to contact the Service Centre in case the pump continues to not work
properly.
If the pump stops suddenly, one of the following cases could be happened:
• Ball bearing failure;
• Burnout or winding discharge, it results fault;
• An high power supply overload;
• If the reason is due to an overload, the installer could supply a right power supply, other-
wise contact qualifies Service Centre.
If the pump stops suddenly, one of the following cases could be happened:
• Ball bearing failure;
• Burnout or winding discharge, it results fault;
• An high power supply overload;
• If the reason is due to an overload, the installer could supply a right power supply, other-
wise contact qualifies Service Centre.
If the user detects the electropump starts and stops too frequently it is extremely im-
portant to check the reason, that it could due to an incorrect use. Stop and re-start the
pump, if the above condition continues, it is necessary to address to a Service Centre or
put in touch directly with one of our skilled persons Dreno Pompe.
IN ALL CASES OF DOUBT, IT IS ALWAYS ADVISABLE TO CONTACT A QUALIFIED DRENO POMPE
ENGINEER (*) OR CONTACT DRENO POMPE ASSISTANCE DIRECT ON +39 0429 73276 OR VIA EMAIL
TO: ufficiotecnico@drenopompe.it
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