Riello RS 70 Instrucciones De Instalación, Funcionamiento Y Mantenimiento página 15

CALIBRATION OF THERMAL RELAY
(A)
LAYOUT (A)
Calibration of thermal cut-out 7)(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
• The RS 70-100-130 burners leave 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 cut-out as well.
• The RS 70-100-130 burners have been type-
approved for intermittent operation. This
means they should compulsorily be stopped
at least once every 24 hours to enable the
control box to check its own efficiency at start-
up. Burner halts are normally provided for
automatically by the boiler load control sys-
tem.
If this is not the case, a time switch should be
fitted in series to IN to provide for burner shut-
down at least once every 24 hours.
• The RS 70-100-130 burners are 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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