doc_PB07B102 Pocket Guide

Glossary

AAC – Adaptive Acceleration Control. A new soft start control technique that allows the soft starter to estimate the motor’s speed and control it to match a selected acceleration or deceleration profile.

AC53 Utilisation Code – The specification of a soft starter’s current rating and intended operating conditions.

Auger – a device which uses a screw-like mechanism to move material or liquid, similar to the process that drives shavings up a drill bit and out of a hole during drilling.

Blower – see Fan.

Bow thruster – a steering mechanism in large ships which uses an impeller to force water through a tunnel in the bow below the waterline, causing the ship to turn.

Centrifuge – a machine which separates materials of different

densities (e.g. solids from liquids or liquids from liquid mixtures).

Chipper – a machine which cuts large pieces of wood into chips.

Compressor, centrifugal – a machine which accelerates gas through a housing then converts the velocity energy to pressure energy.

Normally used in heavy industrial applications.

Compressor, positive displacement – see Compressor, reciprocating.

Compressor, piston – see Compressor, reciprocating.

Compressor, reciprocating – a machine which compresses gas using pistons driven by a crankshaft. Small reciprocating compressors (up to 30 HP) are suitable for intermittent use and are commonly found in automotive applications. Larger units (up to 1000 HP) may be used for large industrial applications.

Compressor, screw – a machine which forces gas into a smaller space, using two meshed rotating positive-displacement screws.

Crusher – a machine which crushes material into smaller pieces.

Crusher, cone – a crusher consisting of two cones inside each other.

Material is fed into the top of the large, outer cone and is broken into progressively smaller pieces by the rotation of the inverted inner cone.

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Glossary

Crusher, jaw – a crusher with one fixed side and one moving “jaw”. The crusher is wider at the top than the bottom, and material is fed in at the top and moves down as it is broken into progressively smaller pieces.

Crusher, roller – a crusher with two horizontal rollers which rotate in opposite directions, crushing the material into smaller pieces.

Current limit – (1) a method of soft starting a motor by limiting the maximum amount of current the motor can draw during the start. (2)

The maximum amount of current the soft starter will allow a motor to draw during a current limit start.

Current ramp – a method of soft starting a motor by gradually increasing the amount of current from a specified point to the current limit.

Debarker – a machine that strips bark from logs.

Decanter – a type of centrifuge.

Edger – a machine that cuts large pieces of timber into usable sizes.

Escalator – a type of conveyor which is used to move people up or down, much like a moving staircase.

Fan, axial – a fan with blades that turn around a shaft, forcing air along the shaft and across the axis of the fan.

Fan, centrifugal – a fan which pulls air in near the shaft and forces it out through an opening in the outer edge of the fan casing. A centrifugal fan produces more pressure for a given air volume than an axial fan.

Fan, radial – see Fan, centrifugal.

Full load current – the amount of current a motor will draw when operating fully loaded and at full speed.

Full load torque – the amount of torque a motor will produce when operating fully loaded and at full speed.

Grinder – a machine which reduces the size of small particles through compression and attrition. For machines operating on larger items, see

Crusher.

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Glossary

Gyratory crusher – see Crusher, cone.

Hydraulic power pack – A hydraulic pump which is used to supply pressurised hydraulic fluid.

IP rating – a description of the soft starter’s level of physical protection, according to IEC 60529.

Kickstart – a method of soft starting a motor which uses a high level of current for a short period at the beginning of a current limit or current ramp start.

Locked rotor current – the amount of current a motor will draw in locked rotor situations, including full voltage starts. Locked rotor current is described as a percentage of full load current.

Locked rotor time – the maximum amount of time a motor can safely run at locked rotor current.

Locked rotor torque – the amount of torque a motor will produce at locked rotor current (such as a full voltage start). Locked rotor torque is described as a percentage of full load torque.

Mill, ball – a machine which grinds or mixes materials such as ores, chemicals, ceramics and paints. The machine consists of a horizontal cylinder which is rotated, causing the grinding medium, commonly stainless steel balls, to repeatedly crush the material inside into a powder.

Mill, hammer – a machine which crushes material into smaller pieces.

Hammers attached to rotating disks repeatedly strike the material until it is small enough to fall through openings at the bottom of the mill.

Mill, roller – a machine which crushes material into smaller pieces.

Material is passed between two horizontal rollers which rotate in opposite directions, crushing the material into smaller pieces.

Milliscreen – a machine which separates solids from slurry, using an inclined rotating drum with perforated sides.

Mixer – a machine which combines ingredients.

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Glossary

Nameplate rating – See Full load current.

NEMA – a description of the soft starter’s physical format, according to the National Electrical Manufacturers’ Association standard.

Pelletiser – a machine which turns powders into pellets.

Planer – a machine which draws boards over a cutting head to reduce them to a specified thickness.

Press – a machine which changes the shape and internal structure of metals (usually steel).

Pump – a machine which moves fluids.

Pump, bore – a submersible pump with a small diameter, suitable for operation down bores.

Pump, centrifugal – a pump with an impeller which causes fluid to rotate and move from the inlet to the outlet under its own momentum.

The fluid’s velocity increases as it progresses through the impeller passage. Diffuser, ring or volute cavities reduce the velocity of the fluid and convert the energy into pressure energy.

Pump, positive displacement – a pump which reduces the volume of the pump chamber to cause the fluid to move. Positive displacement pumps may be used for viscous fluids, and include rotary (lobe, screw or gear pump) and reciprocating (piston or diaphragm pump) types.

Pump, slurry – a centrifugal pump for pumping slurry.

Pump, submersible – a pump which is submerged in the fluid to be pumped. The sealed motor is close-coupled to the pump body.

Pump, vacuum – a pump which removes gas from a sealed chamber in order to create a partial vacuum. Multiple vacuum pumps may be used together for a single application.

Re-pulper – a machine which re-pulps raw product for further processing.

Rotary table – a large rotating table which is used to sort or move material.

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