BUSCH COBRA ATEX NC 2500 B, Instruction Manual

Page: 36 / 44

11 | Troubleshooting
36 / 44 Instruction Manual COBRA NC 2500 B WCV_EN_en
Problem Possible Cause Remedy
The machine does not start. The motor is not supplied
with the correct voltage.
• Check the power supply.
The rotors are jammed or
seized. • Turn the screw rotors
manually from the rotor
access plug (PMR).
• Repair the machine (con-
tact Busch).
Solid foreign matter has en-
tered the machine. • Remove the solid foreign
matter or repair the ma-
chine (contact Busch).
• Install an inlet filter if nec-
essary.
The resistance thermome-
ter (TSA) reached the
switch point. • Let the machine cool
down.
• See problem “The ma-
chine runs too hot”.
Corrosion in the machine
from remaining condensate. • Repair the machine.
• Check the process and
follow the recommenda-
tion in case of
Conveying
Condensable Vapours
[
► 24] .
The motor is defective. • Replace the motor.
The machine does not
reach the usual pressure on
the suction connection. Suction or discharge lines
too long or section diameter
too small. • Use larger diameter or
shorter lines.
• Seek advice from your
local Busch representa-
tive.
Process deposits on the
pumping components • Flush the machine.
If an inlet screen or an inlet
filter is installed, it can be
partially clogged. • Clean the inlet screen or
replace the inlet filter car-
tridge.
The machine runs in the
wrong direction. • Check the direction of ro-
tation, see Wiring Dia-
gram Three-Phase Motor
(Pump Drive) [
► 19] .
Internal parts are worn or
damaged. • Repair the machine (con-
tact Busch).
The machine runs very
noisily. Wrong oil quantity or un-
suitable oil type. • Use one of the recom-
mended oils in the cor-
rect quantity, see
Oil
[ ► 38] .
Defective gears, bearings
or coupling element. • Repair machine (contact
Busch).