Riello Burners RS 190 Instrucciones De Instalación, Funcionamiento Y Mantenimiento página 12

CALIBRATION OF THERMAL RELAY
(A)
LAYOUT (A)
Calibration of thermal cut-out 8)(A)p. 3
This is required to avoid motor burn-out in the
event of a significant increase in power absorp-
tion caused by a missing phase.
• If the motor is star-powered, 400 V, the cursor
should be positioned to "MIN".
• If the motor is delta-powered, 230 V, the cur-
sor should be positioned to "MAX".
Even if the scale of the thermal cut-out does not
include rated motor absorption at 400 V, protec-
tion is still ensured in any case.
N.B.
D867
Burner RS 190 leaves the factory preset for 400
V power supply. If 230 V power supply is used,
change the motor connection from star to delta
and change the setting of the thermal cutout as
well.
The RS 190 burner has been type- approved for
intermittent operation. This means it shoulds
compulsorily be stopped at least once every 24
hours to enable the control box to perform
checks of its own efficiency at start-up. Burner
halts are normally provided for automatically by
the boiler load control system.
If this is not the case, a time switch should be fit-
ted in series to IN to provide for burner shut-
down at least once every 24 hours.
The RS 190 burner is factory set for two-stage
operation and must therefore be connected to
control device TR.
Alternatively, if single stage operation is
required, instead of control device TR install a
jumper lead between terminals 6 and 7 of the
terminal strip.
WARNING: Do not invert the neutral with
the phase wire in the electricity supply
line. Inverting the wires will make the
burner go into lock-out because of firing
failure.
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