rulmeca 80LS Manual De Instalación Y Mantenimiento página 12

EN
t) Re-greasable labyrinth seals:
All RULMECA motorized pulleys are hermetically sealed. Standard oil seals are designed to contain oil within the
motorized pulley during normal operating conditions. They are capable of withstanding an internal pressure rise that
occurs as the pulley motor temperature increases.
Optional re-greasable labyrinth seals are available to protect oil seals from harsh operating or maintenance
conditions. Each labyrinth seal provides a barrier of steel and grease to prevent ingress of dust and fluid through the
oil seal.
In abrasive operating conditions labyrinth seals should be periodically grease-purged to flush abrasive dust away
from the oil seal.
In wet and or dirty conditions, where it is common to wash down equipment with high-pressure detergent spray,
labyrinth seals should be refilled with grease after each wash-down. High-pressure sprays remove grease from the
labyrinth seal, removing an important part of the barrier to fluid ingress.
It has to be secured that grease is always seen at the labyrinth gap.
If in some circumstances the re-grease frequency is too high a so-called "Grease Man" is recommended.
Failing to perform necessary labyrinth seal maintenance could shorten service life and voids product
warranty.
u) Pulley Diameter:
The type and size of conveyor belt will determine the minimum allowable motorized pulley diameter. Using a too
small pulley diameter, which does not match the belt, can cause belt de-lamination, belt splice damage and can
shorten both belt and pulley lagging life. Always contact your belting supplier before specifying a pulley diameter.
v) Terminal Box:
RULMECA motorized pulleys are available with terminal boxes or power cords to facilitate electrical installation.
Motorized pulleys with power cords are available up to 4kW.
Two main types of terminal boxes are used:
A compact terminal box equipped with clamp terminals "WAGO" used for motorized pulley types up to 4.0kW
1.
Larger terminal boxes with traditional threaded brass terminals.
2.
Switch off motorized pulley power supply and control circuit(s) before opening terminal box.
Each terminal box has one or more conduit nipples and a cover plate. The cover plate should be removed to facilitate
termination of power and control wires within the terminal box. After wire connections are made cover plate should be
replaced.
Terminal boxes should never be disassembled or removed from the end of the shaft to reorient conduit nipple
location.
Modifications to terminal boxes should only be made by an authorized RULMECA service centre or after obtaining
permission and instructions, in writing, from RULMECA.
A wiring diagram is placed Inside the terminal box on the back of the terminal box cover.
Dismantling and reassembling terminal boxes could cause short circuits within the internal wiring, which is
factory set (and tested) and would void product warranty.
w) Frequency Converter:
It is essential that each Frequency Converter be set within the motor's allowable operating spectrum. For
RULMECA motorized pulleys the allowable frequency spectrum is 15 Hz to 65 Hz. There will be no more
than 5% torque loss within this range. This means that a RULMECA motorized pulley is essentially a
"constant torque" conveyor belt drive within the allowable frequency range.
If operators attempt to drive the motor outside of the allowable range, then torque loss becomes significant,
motor current draw elevates, motor cooling can become problematic, and product warranty is void.
Do not allow resonant frequencies in the power line to cause voltage spikes in the motor. It is possible for the
Frequency Converter to set up resonant frequencies in the power line between the Frequency Converter and
the motor if the power line isn't too long. Potential resonant frequencies may be eliminated in two ways.
Either by limiting the distance between the Frequency Converter and the motor (some Frequency Converter
manufacturers recommend cable lengths of 10m or less) or simply install a filter on the Frequency Converter
output (available from Frequency Converter manufacturer.)
To avoid any radio-interference the cable from Motor to the Frequency Converter has to be screened and
properly fixed down according to the European Council Directive
"Electro-magnetic Compatibility"
The power and current range of the Frequency Converter have to be selected according to the full-load amperage
given on the motorized pulley data plate.
Do not undersize the conveyor drive. Make certain the conveyor drive provides enough belt pull at each end of the
desired belt speed range. Remember that power (kW) is linearly proportional to frequency (Hz).
For detailed information Refer to the technical precautions in the RULMECA Catalogue.
- EMC-2004/108/EC –
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