4. FUNCTION/TIMING MAGIC
Page 10/12 REV.5 SEPT.2004 Saeco International Group
4.2.2. Magic RD
With the introduction of the Redesign Series the cup warmer is based on PTC output, which has a
continuous voltage of 220 V when the cup warmer is turned on.
The gear resistor in the Redesign Series is found on the instantaneous water heater with the standard values
of 130 Ω / 437 W.
4.3. Water level indicator
The water level in the water tank is monitored by a float fitted with a magnet core. If the water level is too
low, the magnet is no longer within the range of the reed contact, which transmits the low water level signal
to the CPU.
4.4. Flow meter (Turbine)
The machine is also equipped with a flow rate monitoring system. The system checks whether the water
monitoring flow meter (turbine) turns. If no pulses are generated from the turbine within 10 seconds, the
current cycle is interrupted. The fault is indicated by the water low indicator (machine without float) or by
the de-aerate indicator in machines with float (reed sensor). If this control mechanism is activated, the
machine must be de-aerated. During these signals, the pump operates at maximum output. As soon as the
pump has created sufficient flow, the pump output is reduced to approx. 20 l/hr.
The water quantity is generally controlled according to the coffee quantity programmed through the flow
meter (turbine) pulses.
4.5. HWS valve (steam operation)
The HWS valve is required for water and steam dispensing, as well as during de-aeration (machines without
rapid steam systems).
If the HWS valve is opened during brewing, the coffee flow is interrupted and the Water Low De-aerate
indicator (machines without float) or the message Close Dial (machines with display) appears. As soon as
the HWS valve is closed, the brewing process will continue.
The operating temperature during steam dispensing is approx. 125°C. The steam button is pressed to activate
steam production. Steam dispensing occurs via the HWS valve (machines without rapid steam systems).
The pump pulses the steam dispensed. This means that constant steam dispensing is ensured over a long
period of time. The flow rate of the pump is adjusted on the basis of the thermoblock temperature. If the
temperature is too low, the pump pulses are slowed down. This may occur, for instance, when the steam is
dispensed before the steam temperature is reached.
Once the steam has been dispensed, the HWS valve closes and the steam button must be pressed for normal
operating mode (machines without rapid steam or instant steam systems). The temperature indicator flashes
until the machine has cooled (the message Overheating appears in machines with digital display) and the
machine cannot dispense coffee. Cooling can be achieved by dispensing hot water. The pump functions at
maximum output and the heating remains turned off as long as the Overheating signal remains or
temperature indicator flashes. These measures ensure that the cooling process is accelerated and the flashing
indicator or overheating signal will disappear after a few seconds.
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