Sensata Technologies CHIP CONVEYOR MOTOR CONTROL Application Note

APPLICATION NOTE

CHIP CONVEYOR MOTOR CONTROL
IN MACHINE TOOLS

Background

A chip conveyor system is very common
on CNC machine tools; it can be part of the
machine or it can be offered as an accessory.
The main function of a chip conveyor system is
to remove the cutting excess material, which
can be metal or plastic, from the machine tool.
A chip conveyor is commonly driven using
a small to medium size three-phase motor,
and the conveyor control system is generally
mounted next to the motor in the conveyor.
Reliability is a prime concern on these
systems, since repair downtime could be very
costly, so this should be considered when

designing the control system

for a chip conveyor. It also

In addition to

needs to have capacity

having standard start/

stop and reversing control,

using a Motor Starter can add

other features that help reduce

current surges and extend

the life of the motor and the

conveyor mechanical

parts

for reversing, in case

chips get stuck.

Solution

Control of start/stop and forward/reverse of
the conveyor motor can be achieved using
electromechanical contactors, but this has
several disadvantages: it requires 2 contactors
plus an interlock system, and there is also a
reliability issue since the life expectancy of an
EMR solution is much lower (typically lower
than 100K cycles)
Solid State Relays and Contactors are a
great solution for this application, being more
compact than the equivalent EMR solution and
having higher reliability. For a simple control
system, a basic reversing contactor like a
Solicon DRC, can be used to provide start/
stop and forward/reverse control.
For a more complete control solution a Hybrid
Motor Starter, such as the DRMS, would be
an excellent option. This device combines
EMR and solid state switching technology on
an integrated solution in a slimmer 22.5mm
package. In addition to having standard start/
stop and reversing control, using a Motor
Starter we can add other features such as
overload detection (there is no need to add
an external overload relay) and soft start/stop
function, which can help to reduce current
surges and extend the life of the motor and the
conveyor mechanical parts.

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RECOMMENDED PRODUCTS

Reference

on Diagram

Product Features Function Brand

1 DRC Series

2 DRMS Series

DIAGRAM

• Solid state contactor

• Reversing of 3-phase motors up to 5HP (3.7kW)

• Available with auxiliary contacts

• Built-in overvoltage protection

• Hybrid relay technology

• Reversing of 3-phase motors up to 4kW

• Soft start/stop capability

• Overload protection

Conveyor Start/Stop

with Fwd/Rev

Conveyor Start/Stop

with Fwd/Rev and

Overload Protection

1 2

Crydom

Crydom

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