Year: 2025

Accuray Systems

AccuRay designed, manufactured and marketed computer-based automation and management

information systems for manufacturing processes to save raw materials and energy,

increase productivity, lower costs and improve product quality. AccuRay automation systems

controlled manufacturing processes in the pulp and paper, rubber, plastics, textile and metals industries.

AccuRay systems measured the basic properties of materials, such as weight, moisture, thickness, width, opacity and component content.

The technologies for performing such measurements employed a variety of physical and electronic principles that included nuclear,

X-ray, infrared, radio frequency, optical, pneumatic and electromagnetic techniques.

AccuRay technology and expertise has helped ABB maintain its status as the leading provider

of measurement and control technologies for the Pulp and Paper industries.

With the introduction of open standards for operating

systems and standard PC hardware and software, a new

challenge was introduced to process automation system owners.

In the past there was a level of protection from frequent software

updates and constantly increasing connectivity requirements,

now these parameters are in a constant state of flux. The

industry has embraced this technology as process automation

supplier’s shift from proprietary hardware and software to

custom-off-the-shelf (COTS).

ABB’s electronic releases of PR series offer a

variety of programmable protection functions for

all mentioned circuit breaker types:

• Overload protection L

• Selective short circuit protection S

• Instantaneous short circuit protection I

• Earthfault protection G

Further options available (but not limited to):

• Zone selectivity

• Dual protection settings

• Directional short circuit protection

• Reverse power

• Under-/overvoltage protection

• Annunciation of measured values, alarms

• Maintenance data

• Integration into a plant wide process

control system

In order to satisfy other incomer requirements

there are further options:

• Load break switches

• Moulded case circuit breakers (MCCBs)

MNS incoming solutions are verified by testing in

accordance with IEC 61439 series, in addition to

IEC 60947-1 required for the individual apparatus,

and engineered to meet the requirements of

IEC 61641. This ensures ABB’s offering of ‘Proven

Safety Plus’ for operators and plant.

Incoming options

All ACBs have as a minimum the following

features:

• Manual charging lever and ‘charged’ indication

• Manual open/close push buttons

• Mechanical ‘open’/’closed’ indication

• Mechanical signalling of ‘overcurrent’ release

• 4 auxiliary contacts

Project specific options

• Gas sealed connections to the main busbars

(separation wall)

• 3 or 4 pole solutions

• Withdrawable/fixed configuration

• Top or bottom cable entry/bus duct

• 50% or 100% neutral

• Shunt opening/closing release

• Undervoltage release

• Electrical signalisation of ACB status

• Key locking facilities

• Shutter locking facilities

• Mechanical indication ‘racked in’/’racked

out’/’test isolated’ position

• Locking in racked in/racked out/test

isolated position

• Switch disconnector option

• ACB handling truck

• Configuration and test unit

A condaptor unit facilitates the horizontal

distribution of power from the vertical

distribution bars for 6E/4 and 6E/2 modules, see

illustration on page 35. The condaptor enables

the modules to be located adjacently within the

same horizontal position of the cubicle.

Modules of size 6E and above are connected

directly to the vertical distribution bars.

System highlights

• Although IEC 61439 series requires 200

connection cycles only, the MNS contact system

is tested, certified and proven for contact cycles

(plug in/unplug) up to 1,000

• The contacts are silver coated as standard

• Full individual phase segregation assured prior

to the connection of the power contact.

Power contact

Connection to the distribution bars is realized

using the precision-engineered MNS power

contacts. The power contact is characterized by a

turn-able bearing, thus decoupling cable stress

and electrical contact. Consequently any cable

bending forces cannot affect the stability of the

power contact.

The mechanical stabilisation is taken over by

the supporting plate and the contact spring

where the contact fingers ensure positive

electrical contact. Contact fingers are silver

plated as standard.

The contact has been subjected to several tests in

order to prove the sophisticated design and the

high quality:

• Verification by testing acc. IEC 61439 series

• Corrosion test acc. DIN 50017 and

IEC 60068-2-60

• Crimping quality check acc. IEC 61238-1

• Vibration and shock test acc. IEC 60068-2-6

and IEC 60068-2-27

System highlights

• Functional areas are separated from each other

in accordance with IEC 61439 series.

• Power cables are fully separated from the control

and communication cables, thus avoiding

electromagnetic interferences.

• Different access rights to cable compartments

can be granted using different key locks.

The basic elements of the MNS iS frame

construction are “C” shaped steel profiles with

a 25 mm hole pitch according to DIN 43660.

This 25 mm equals the dimension of 1E used

in MNS to define the area usage within

the switchgear.

Each cubicle is precision constructed by bolting

horizontal and vertical profiles together, to form

a rigid modular structure. The assembly is

maintenance free as a result of the construction

method utilizing a combination of thread locking

ESLOK screws with bolted pressure plates and

thread forming screws.

The profiles are galvanic protected (Zn or AL/Zn)

against corrosion.

As a standard, power cabling and control wiring

are strictly separated within MNS iS. The

switchboard is structured as follows:

1 Equipment compartment

All equipment, including the standard motor

starter modules (MStart) in withdrawable

design, is situated therein. The compartment

can be divided in horizontal and vertical

sub-compartments.

2 Control cable compartment

Contains the motor control devices

(MControl), control cables and terminals.

3 Power cable compartment

Contains power cables and connection units.

4 Busbar compartment

Contains the MNS main busbar system and

distribution bars. The distribution bars are

embedded in the multifunction separation

wall (MFW) which is located between the

equipment compartment and the busbar

compartment.

System highlights

• Functional areas are separated from each other

in accordance with IEC 61439 series.

• Power cables are fully separated from the control

and communication cables, thus avoiding

electromagnetic interferences.

• Different access rights to cable compartments

can be granted using different key locks.

The basic elements of the MNS iS frame

construction are “C” shaped steel profiles with

a 25 mm hole pitch according to DIN 43660.

This 25 mm equals the dimension of 1E used

in MNS to define the area usage within

the switchgear.

Each cubicle is precision constructed by bolting

horizontal and vertical profiles together, to form

a rigid modular structure. The assembly is

maintenance free as a result of the construction

method utilizing a combination of thread locking

ESLOK screws with bolted pressure plates and

thread forming screws.

The profiles are galvanic protected (Zn or AL/Zn)

against corrosion.

Switchboard construction

MNS iS as part of the ABB low voltage switchgear

solution uses the well proven ABB MNS standard

design aspects. MNS aspects described in this

section are fully applicable to MNS iS.

MNS system is a verified low voltage switchgear

design in accordance with IEC 61439 series and IEC 61641.

The consistent application of the modular

principle both in electrical and mechanical design

as well as the use of standardized components

allows its flexible and compact design.

Depending on operating and environmental

conditions different design levels are offered.

Notable system advantages with regard to

design aspects:

• Optimum personal protection

• Design verified by testing

• Arc fault containment acc. criteria 1-7

• High operational reliability and availability

• Earthquake-, vibration- and shock-proof

designs are available

• Maintenance-free busbar construction

• Simple retrofitting procedures

• Compact, space-saving design

• Easy project and detail engineering through

standardised components

The switchboard is divided into vertical and

horizontal compartments thus separating

different functional areas.