Wilo RP Serie Instrucciones De Instalación Y Servicio página 23

ENGLISH
– For three-phase 3~230/240V:
available at additional costs.
Motor overload protection:
– Pumps of connection sizes DN
25/30/40 with impellers 80 mm
OD (1-or 3-phase) run non-over-
loading at all possible operational
conditions and do not require mo-
tor overload protection.
– Motors of all other types and sizes
are internally equipped with ther-
mal contacts (WSK). When used
in conjunction with an external trip
device e.g. SK 602/622 or C-SK
(extras) the pump is de-energized
on undue temperature increase in
the motor windings. Restart is
possible only after the motor has
cooled down. The use of either
the trip device SK 602/622 or
C-SK is strongly recommended.
Such trip device is not required
when using
speed control gear which already
integrally contain a trip device.
– Automatic twin pump control re-
quires the use of the S2R 3D con-
trol box, which also contains the
trip device for motor overload pro-
tection.
Variable motor speed selection:
All pumps are equipped with a ma-
nual 4-speed selector. At the MIN-
setting, motor speed is reduced to
40...70 % of rated maximum speed
WILO automatic
with the power input down to
approx. 50 %.
– Single-phase pumps are equip-
ped with a rotary switch at the ter-
minal box (Fig. 1a, Item 1).
– Non-overloading
pumps have, in addition to the
speed selector switch, the facility
for connections to an automatic
2-speed controller (S2R-h, time-
controlled speed change).
– Manual speed change of three-
phase pumps is by means of a 4-
step plug at the motor terminal
box. In addition, automatic 2/4-
speed control is also applicable
(Fig. 1b, Item 1).
Switch/Control gear:
Switchboxes and control units for
the matching pump capacity to ac-
tual load demand are available from
the supply range of WILO Automatic
Pump Control Systems.
4.2 Scope of supply
– Pump, complete,
– Installation and Operating Instruc-
tions.
4.3 Accessories
Accessories available and/or requi-
red on separate order:
– Unions for pipe connections of
screwed end pumps,
– SK 602, SK 622, C-SK (3~ 400/
415V only) overload trip relays,
single-phase
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