What is Type 2 Coordination?


What is Type 2 Coordination?

The International Electrotechnical Commission (IEC) developed short circuit performance criteria for contactors and starters called Type 1 coordination and Type 2 coordination. This defines motor controller protection levels following a short circuit fault.

In order to achieve this performance, the combination of a motor controller (contactor or starter) and short circuit protective device (manual motor protector, circuit breaker or fuse) must meet the following criteria as specified by IEC 60947-4-1 — Low voltage switchgear and controlgear — Part 4-1: Contactors and motor-starters — Electromechanical contactors and motor-starters

Type 1 Coordination:

Under shortcircuit Conditions, the contactor or starter shall cause no danger to persons or installation and may not be suitable for further service without repair and replacement of parts.

Type 2 Coordination:

Under short circuit conditions, the contactor or starter shall cause no danger to persons or installation and shall be suitable for further use. The risk of contact welding is recognized, in which case the manufacturer shall indicate the measures to be taken in regards to equipment maintenance.

In this case, the contactor/starter is  able to continue use after the occurrence of a short circuit fault. Light contact burning or tack welding may occur provided the contacts are easily separable.


1. Safety: Type 2 coordination is intended to provide safety for operating personnel, facility and the installed equipment.

2.  Reduced costs: When a starter is properly protected from short circuits, all  components of the branch circuit remain intact and operational. Only fuses  may need to be replaced. Savings result from a reduction in labor required  to perform maintenance after  a short circuit and in the amount of replacement parts and required equipment. Savings are also realized by minimizing spoiled or lost production in a continuous process environment, such  as may occur in some food and chemical process plants.

3. Increased productivity: The manufacturing process relies on continuous  motor operation. If starters are damaged and must be repaired or replaced,  the motors are shutdown and the manufacturing process stops. By implementing Type 2 coordination, manufacturing processes should function with minimum disruption from short circuits on the motor circuits

Type 2 protection provides confidence that motor control components will be operable following a short circuit fault. This reusability translates into hundreds or even thousands of dollars in savings due to reduced downtime and replacement costs.

TYPE 2 Coordination = Safety + Less Downtime = Dollar