COFFEtek VITRO S2 Series, Technical Manual

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13 28/02/2017 Revision 1 VITRO S2/3
Circuit Description
27. If the beverage machine is supplied by a 230V~ single-phase supply from a 10A or 16A
outlet (or from a 13A domestic outlet), only 15A fuse protects the heater circuit, a solid state
relay (SSR) contact and high temperature cut-out is placed in the circuit of heater
28. The SSR switches the supply to the heaters as directed by the MPU Controller in response
to data received from the temperature sensor part of the temperature/level probe, thus
maintaining the water in the boiler at the correct temperature. However, if the water in the
boiler starts to boil, the high temperature cut-out remove the supply to the heater. Reset
buttons for cut-out is accessible at the top of the machine.
29. A 230V~ ac main supply is taken from terminal block to the Power Supply PCB via the
on/off switch. The Power Supply PCB provides DC supplies of 24V, 12V and 5V. The 24V-
dc output supplies the ingredient motors, whipper motors, extract fan, SSR and solenoid
operated valves. The 12V-dc output supplies the MPU Controller Board and operational
coin acceptor (if fitted).
30. The MPU Controller Board continually checks the status of input devices connected to
plugs J1 and J3, and responds to any change of state by signalling the operation of the
relevant output devices via on-board current drive transistors. Thus, for example, the water
level probe controls the operation of the inlet valve and the temperature sensor controls the
operation of the SSR.
31. The dispensing of a beverage begins with the keypad selection, which is scanned by the
MPU Controller Board via a ribbon connector. Which passes through the button control
board to the MPU. Control Signals corresponding to the required actions are then
generated by the MPU Controller to operate the relevant output devices in the correct
sequence and for the specified duration. Operator data information is sent in parallel form
to the (LCD) Display.