Applications; Variants; Location And Mounting; Location - Grundfos LC 108 Installation And Operating Instructions Manual

2.1 Applications

The LC 108 enables:
• control of one pump based on signals from float switches or
electrodes,
• selection of automatic test run during long periods of inactivity
(every 24 hours),
• battery back-up in case of mains supply failure (accessory for
certain variants),
• starting delay within the range from 0 to 255 sec. (random)
after returning from battery operation to mains operation
(resulting in an even mains load when several pumping
stations are started up at the same time),
• selection of automatic alarm resetting,
• selection of automatic restarting,
• setting of stop delays matching the actual operating
conditions,
• indication of liquid level,
• alarm indication of:
– inadmissibly high liquid level,
– overload (via motor protection relay),
– overtemperature (via PTC resistance or thermal switch in
motor),
– wrong phase sequence (only certain variants),
– mains supply failure (only certain variants),
– defective float switch, electrode or flow switch,
– dry running.
As standard, the LC 108 has one alarm output for common alarm.
Certain variants have an additional alarm output for separate
high-level alarm.
Furthermore, the controller incorporates a buzzer (only certain

variants).

2.2 Variants
The actual controller type, voltage variant, etc. are stated in the
type key on the nameplate situated on the side of the controller
cabinet.
The LC 108 is available for either direct-on-line starting or
star-delta starting.
The LC 108 can be connected and set to operation/control in
7 different ways, see sections 4. to 10.:
• Section 4. Systems with 2 float switches.
(Electrodes can also be used.)
• Section 5. Systems with 3 float switches.
(Electrodes can also be used.)
• Section 6. Systems with 4 float switches.
(Electrodes can also be used.)
• Section 7. Systems with 2 electrodes.
• Section 8. Systems with 3 electrodes.
• Section 9. Systems for filling applications.
• Section 10. Systems for drainage applications.
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3. Location and mounting

Warning
Before starting any work on pumps used to pump
liquids which could be constituted as being
hazardous to health, thorough cleaning/venting
of pumps, pits, etc. must be carried out
according to local regulations.
Before making any connections in the LC 108 or
work on pumps, pits, etc., it must be ensured that
the electricity supply has been switched off and
that it cannot be accidentally switched on.
The installation must be carried out by authorized personnel in
accordance with local regulations.

3.1 Location

Warning
The LC 108 controller and an EEx barrier, if
required, must not be installed in explosion
hazard areas.
Only float switches approved for use in explosion
hazard areas may be used. The float switches
must be connected via an EEx barrier, e.g.
Grundfos number 96440300.
The LC 108 can be mounted at ambient temperatures ranging
from -30 °C to +50 °C.
Enclosure class: IP65.
When installed outdoors, the LC 108 must be placed in a
protective shed or cupboard.
The LC 108 must not be exposed to direct sunlight.

3.2 Mounting of LC 108 for direct-on-line starting

Before mounting, remove the transport protectors, if any, from
inside the cabinet.
Mount the LC 108:
• on a plane wall surface,
• with the Pg cable entries pointing downwards (additional Pg
cable entries, if required, must be fitted in the bottom plate of
the cabinet),
• with four screws through the mounting holes in the back plate
of the cabinet, see fig. 1. The mounting holes must be bored
with a 4 mm bore. Fit the screws into the mounting holes and
tighten securely. Fit the plastic caps supplied with the
controller on the screws (IP65).