DUO, DUO 2V, DUO 2
NP-DUO-17_11-2023-MD - 18 - 11/2023
8.2.6. Equipotential bonding socket
The socket allows an equipotential bonding. (Fig.10)
9. PRODUCT FUNCTIONALITY
Compressor with suction unit(Fig. 1)
The air pump (1) draws in atmospheric air through an inlet filter (8) and compresses it through
a non-return valve (3) into an air tank (2) from which the device draws compressed air. If the
pressure in the air tank drops to the switch-on pressure, the pressure switch (4) turns on the
compressor and the compressor supplies compressed air into the air tank until it reaches the
switch-off pressure, when the compressor switches off. The pressure hose is vented through the
relief solenoid valve (13) once the air pumpis shut off. The safety valve (5) prevents the pressure in
the air tank from rising above the maximum allowed value. The drain valve (7) drains condensate
from the air tank. Compressed, oil-free filtered air is stored in the air tank ready for use.
Condensate must be drained from the air tank at regular intervals (see Chapter 19.1).
The suction pump (36) (two aggregates on DUO2) draws in air, thereby creating vacuum in the
suction lines that are connected to the device and is a source of vacuum for removing foreign
substances from the doctor’s work area. This air is then exhausted through an exhaust line routed
outside the operator's work area.
Compressor with suction unitand membrane dryer (Fig. 2)
The air pump (1) draws in air through an inlet filter (8) and compresses it, feeding it to the cooler
(14) through the filter (15) and the check valve (3) into the dryer (9), and feeds the clean and dry
air into the air tank (2). A part of the air is released from the dryer with the captured moisture,
which is manifested as a light air stream along the body of the dryer (9). Condensate from the filter
is automatically drained at regular intervals into the collecting bottle via the condensate drain
solenoid valve (16). The dryer ensures continuous drying of the compressed air. The drain valve
(7) drains condensate from the air tank when drying performance is checked. Compressed, oil-free
filtered air is stored in the air tank ready for use.
For the membrane dryer to work as intended, the dryer is connected directly to the air tank without
the use of a check valve. As the membrane dryer contains selective membrane fibres, there is a
small amount of air leakage through them (about 0.5 bar/30 min).
As a result, there is a gradual, slow drop in pressure even when there is no demand for
compressed air (from the air tank), however, this is not a malfunction.
The pressure vessel does not need to be drained.
The suction pump (36) (two aggregates on DUO2) draws in air, thereby creating vacuum in the
suction lines that are connected to the device and is a source of vacuum for removing foreign