1. Motor Starter Coordination
-Implications
-Benefits
M Butler July 05

2. Coordination -A practical definition:
“Selection of starter components:
The short circuit protection element, (eg:Fuses/ Circuit breaker)
The switching (Contactor)element
The motor protection (Thermal Overload/ circuit breaker)element
..such that the occurence of a short circuit fault will result in a predictable outcome”.
However different levels of coordination will lead to different results following a short circuit fault
M Butler July 05

3. Type 2 coordination- Definition according to BS/EN 60947-4-1
« Effective limitation of the fault condition with no damage resulting to the components of the motor starter other than light tack welding of contactor main contacts which can easily be broken»
However:
3 levels of coordination are considered by the standards
Type 1 coordination to BS EN
Type 2 coordination to BS EN
Total coordination to BS EN
M Butler July 05

4. BS/EN 60947-4-1 minimum requirements:
Type 1 coordination
Type 2 coordination
Allows damage to all
components when confined within their enclosure
Allows tack welding of main
poles (easily broken) and a change of O/L characteristics
Allows only tack welding of
main poles
(easily broken)
M Butler July 05

5. Type 1 coordination -minimum performance required following a short circuit fault:
Damage to / destruction of starter components is acceptable, but there must be:
No danger to personnel eg: ejection of damaged components from the enclosure (Note risk if panel door open & panel live)
No damage to external installation,
Effect of a short circuit fault:
Downtime to replace components/ rebuild starter will be significant
M Butler July 05

6. Type 2 coordination- minimum performance required after a short circuit
Weld of contactor main contacts acceptable, provided weld is easily broken, and there must be:
No damage to the installation
No danger to personnel
No need to replace components
Effect of a short circuit fault:
Downtime reduced, compared to type 1 coordination Checking contactor main pole contacts ( breaking tack welds if necessary) & replacing fuse links where used is required
M Butler July 05

7. Total coordination is now a practical possibility
To achieve type 2 coordination selection of the correct components is vital! Proven Type 2 coordination is the minimum requirement to ensure safety- But technology has moved on……..
Total coordination is now a practical possibility
M Butler July 05

8. Requirements for Total Coordination for compliance with BS EN 60947-6-2
Starter must be a CPS (Control and Protective Switching) device.
No damage to starter assembly acceptable
Ongoing electrical life must be guaranteed
No damage to the installation acceptable
No danger to personnel acceptable
Equipment may immediately be reset and restarted, once short circuit fault removed
Effect of a short circuit fault:
Minimal downtime. -Removal of fault followed by resetting and restarting of equipment is all that is necessary
M Butler July 05

9. Telemecanique independently certified CPS Motor starters with Total coordination
Single product solution
TeSys model U up to 32A
Single product solution with diagnostics
Tesys model U with Multi- function module
Single product solutions with AS-I capability
Tesys model U with AS-i module
Single product solutions with diagnostics and full communications capabiilty
Tesys model U with Multifunction module and Modbus or Canbus coms module
M Butler July 05

10. Tesys model U provides unique benefits enabling maximisation of machine uptime
Total coordination
Minimum downtime following fault
No damage to installation following a fault
No reduction in service life
Easier selection of correct components to ensure integrity of the installation
Diagnostics capability- Retention and downloading of data:
Last 5 trip occurences
Reason for trip- (short circuit or thermal)
Total no hours run
No of operations
M Butler July 05

11. Summary
Effective coordination of starter components is essential for safety and minimum downtime following a short circuit fault
Type 1 coordination must be considered unacceptable for all but the simplest installations where downtime in the event of a fault is not critical
Type 2 coordination can reduce downtime in the event of a short circuit fault, but requires careful selection of components
Total coordination virtually eliminates downtime due to short circuit faults. Selection of a CPS device is simple
M Butler July 05