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Elektr ische Funktionsbeschreibung
Elektrische Funkt ionsbeschr eibung
Elektr ische Funktionsbeschreibung
Elektrische Funkt ionsbeschr eibung
Elektrische Funktionsbeschreibung
The condensate level and the discharge times are deter-
mined with the aid of two capacitive probes (two-position
measurement) arranged in a vertical line along a sensor
tube and connected to a waiting circuit. Information on the
respective states of the upper and lower probe is obtained
by waveform comparison. When both probes are covered
by condensate, the discharge procedure is started - after
a delay of approx. 2 seconds - and the alarm/monitoring
circuit is activated. As soon as the solenoid valve opens,
i.e. when the condensate discharge starts, the electronic
system determines the pressure-dependent time required
until the lower probe will again be free of condensate.
This figure serves as a basis for calculating the necessary
opening time of the solenoid valve up to final discharge
without loss of compressed air. At the end of this period,
the BEKOMAT will be completely empty; the discharge
procedure is then stopped, and the alarm/monitoring
circuit is deactivated.
In the event of no condensate discharge, e.g., if the
condensate discharge pipe is blocked or the pressure
drops below the required minimum the alarm/monitoring
circuit will regulate the further sequence of functions (see
below “Alarm/monitoring control”, 1. and 2.”).
Alarm monitoring control
The BEKOMAT electronic system ensures permanent
monitoring of the operating states of the condensate drain.
Any malfunctions will be signalled via the potential-free
alarm contact. The control operates in a fail-safe mode.
Consequently, an alarm signal can still be relayed via the
potential-free contact, if the power supply to the BEKO-
MAT is interrupted. The circuit diagrams on page 9 show
the de-energised state of the BEKOMAT with the poten-
tial-free alarm contact 3.0-3.1 closed (alarm mode).
When voltage is applied, the alarm relay picks up and
terminals 3.1-3.2 of the potential-free contact are closed
(normal operating state). In the case of a malfunction, the
alarm relay drops out and terminals 3.0-3.1 are connected
(alarm mode).
1.
The situation may arise where the discharge procedure
is started, but the lower probe remains covered, so that
the required opening time of the solenoid valve cannot
be calculated. In this case, the discharge procedure is
interrupted after approx. 2.5 sec., and is only restarted
when the upper probe is covered again.
2.
Under certain conditions mentioned above, the lower
and upper probe of the BEKOMAT may remain per-
manently covered. In this case, the discharge proce-
dure is interrupted after approx. 2.5 seconds and
restarted after a delay of approx. 2 seconds. This
procedure is then repeated until the alarm signal is
triggered.
The alarm signal occurs after approx. 60 seconds, and
the alarm circuit takes over the subsequent control of the
solenoid valve.
In the alarm mode, the solenoid valve is first closed, and
the alarm relay drops out, while the potential-free chan-
geover contact goes into off-position. The alarm signal is
maintained, and the alarm circuit actuates the solenoid
valve approx. every 4 minutes for a period of approx. 7.5
seconds. The alarm mode LED continues to flash. This
switching function is repeated until the condensate drain
is again operating under normal conditions.
The solenoid valve can be actuated by means of the test
switch at any time; the valve will stay open as long as the
switch is being pressed. During testing, the red LED
flashes and, after pressing the test switch for about one
minute, an alarm signal is given via the potential-free
contact. After releasing the test switch, the condensate
drain will revert to normal operation.
The circuitry of the BEKOMAT is designed in such a way
that - after relevant changes of the PCB components and
correct adjustments, which must be done at our works -
it can also function with direct voltage. In addition to
mounting the necessary components on the printed cir-
cuit board, d.c. operation requires fitting of a special
solenoid coil.
LED power: (green)
operating state ‘power supply’ (LED on = voltage is
applied).
LED valve: (yellow)
indication of actuated solenoid valve (LED on = solenoid
valve open).
LED alarm: (red)
alarm and test state indication with flashing frequency of
2 - 3 times per second.
