Riello RL 28/M Instrucciones De Instalación, Funcionamiento Y Mantenimiento página 9

RL 28/M
(A)
RL 38 - 50/M
D3760
(B)
RWF40
(C)
RL 38/M - RL 50/M
THERMAL RELAY
(D)
RL 38/M
208-
230 V
F A T 6
L 1,5
2
mm
a - d : red
b - c : white
D3165
D3759
RL 50/M
380- 208- 380-
460 V 230 V 460 V
T 6 T 6 T 6
1,5 1,5 1,5
D1910
8
SCHEMA (A)
RL 28/M electrical connection
single-phase 230V power supply.
Cable section not indicated: 1.5 mm
LAYOUT (B)
RL 38/M - 50/M electrical connection
three-phase 208-230/380-460 V power supply
with neutral phase wire.
Cable section not indicated: 1.5 mm
LAYOUT (C)
Power regulator RWF40 electrical connec-
tion.
(modulating operation)
Key to wiring layouts (A) - (B) - (C)
BT - Temperature probe
BP - Pressure probe
IN - Manual burner stop switch
MB - Terminal strip
S - Remote lock-out signal
TL - Limit control device system: 
this shuts down the burner when the boiler
temperature or pressure exceeds the set-
point value.
TR - High-low mode control device system:
controls operating stages 1 and 2. The TR
load control is not required when the regu-
lator RWF40 is connected as its function is
performed by the regulator RWF40 itself.
TS - Safety control device system: 
this operates when TL is faulty.
LAYOUT (D)
Calibration of thermal cut-out 21)(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, 380-460 V, the
cursor should be positioned on "MIN".
• If the motor is delta-powered, 208-230 V, the
cursor should be positioned on "MAX".
Even if the scale of the thermal cut-out does not
include rated motor absorption at 380-460 V,
protection is still ensured in any case.
NOTA
Burners RL 38/M and RL 50/M leave the factory
preset for 380-460 V power supply.
If 208-230 V power supply is used, change the
motor connection from star
, see Fig. (D), and change the setting of the
thermal cut-out as well.
The supply to the auxiliary circuits must be 230 V.
The RL 28/M - RL 38/M - RL 50/M 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 perform checks of its own efficiency at
start-up.
Burner halts are normally provided for automati-
cally by the boiler load control system.
These burners are also fitted for continuous
operation, if they are equipped with control box
LANDIS type LOK 16.250 A27 (interchangeable
with the burner control box LANDIS LAL 1.25).
WARNING
Do not invert the neutral with the phase wire
in the electricity supply line.
2
2
to double star