17
STCS ed 07/02 CAESAR Star
Technical Documentation Technical Documentation
Outputs.
This is a positive square-wave signal with variable ON-OFF ratio (duty-cycle)
that controls the modulation coil of the gas valve and makes it possible to alter
gas pressure to the burner.
Modulator coil
(Y2)
This is a high voltage signal (about 16 kV) for energising the ignition electrode
on the boiler.
Ignition/Detection
electrode
(E1)
This is a single-pole relay which is excited when the burner has to be ignited.
By means of its contact, the adjustment board ignition circuit is controlled.
Request Relay
(K2)
This is a single-pole relay that is excited by the ignition circuit to energise the
main gas valve coils (Y1).
Gas Valve relay
(K3)
This is a single-pole relay for controlling the fan (M1) which is excited when
operation is required.
Fan Relay
(K1)
Adjustments.
For setting the temperature of the doemstic hot water for heating between
40°C and 60°C.
Master Switch
(d.h.w. adjustment)
(S4)
Depending on its position (Natural gas/LPG), it adapts the
modulation parameters for the gas for which the appliance
is set.
Gas switch
(S1)
Gas switch G110
(S2)
For adapting the modulation parameters of the board to
gas G110 (town gas).
Engaged using the jumper on gas switch S1 which must
be shifted onto switch S2.
Absent = Natural
gas
Present = LPG
Absent = Natural
gas or LPG
Present = G110
(with S1 absent)